SYSTEM OF AND PHARMACY: V J. MURRAY, LECTURER ON CHEMISTRY, AND ON MATERIA MEDICA AN© PHARMACY, EDINBURGH. WITH NOTES N. CHAPMAN, M. D. wROEEPSOR OE MATERIA MEUltA IN THE UNIVERSITY OE PENNSYLVANIA > IN TWO VOLUMES. VOL I. NEW-YORK*; PUBLISHED BY SAMUEL WOOD & SONS, NO. 261, PEARL-9TRRET ; AND SAMUEL S. WOOD & CO. NO. 212, MARKET S! BALTIMORE. 1821, District of Pennsylvania, to wit: ********** BE IT REMEMBERED, that on the twenty-first day of Octo* SF \T * ' Jer ' ' n tne ftx'tietu year of the Independence of the United States of % J America. A.D. 1815, Thomas Dobson. of the said district, hath de********** posited in this office the title of a book the right whereof he claims as proprietor, in the words following, to wit: " A System of Materia Medica and Pharmacy : by J. Murray, Lecturer on Chemistry, and on Materia Medica and Pharmacy, Edinburgh. With Notes by N. Chapman, M. D. Professor of Materia Medica in the University of Pennsylvania. In two volumes." In conformity to the Act of the Congress of the United States, entitled, " An *.ct for the encouragement of Learning, by securing the copies of Maps, Charts, and Books to the authors and proprietors of such copies, during the times therein mentioned." And also to the Act, entitled, " An Act, supplementary to an Act, entitled an Act for the encouragement of Learning, by securing the copies of Maps, Charts, and Books to the authors and proprietors of such copies, during the times therein mentioned, and extending the benefits thereof to the arts of designing, engraving and etching historical and other prints." D. CALDWELL, Clerk of the District of Pennsylvania TO J. MURRAY, M. D. &c&c. My Dear Sir, I HAVE had printed the present edition of your System of Materia Medica and Pharmacy, to serve as a Text Book to my Lectures. In making this selection, I am not sensible that I was, in any degree, influenced by the partiality of friendship. As an ele- Ititary treatise, the work has confessedly no ordinary preten-t jm, and it seemed to me to be peculiarly well suited to my S4rpuie, as exhibiting within a narrow compass, a very correct of *he existing state of the science. NeverJheless, you will perceive in the notes which are added, jtffat I do not always entirely agree with you. The differences OF THE GENERAL PRINCIPLES 44 tile, wax seems to have to the fixed oils. This substance, though formed perhaps by the bee, is also a product of vegetation ; it is yielded by the leaves and fruit, and it is sometimes intimately mixed with the resin, gum, or extractive matter of plants. It is insoluble in water, and is soluble in verv small quantity with the aid of heat in alcohol. It combines with the fixed alkalis, though with some difficulty. It unites easily with the expressed oils. It melts at a moderate heat. By distillation in close vessels it affords an ccid, and a considerable quantity of thick oil, a small quantity of charcoal being the residuum. Resin. This principle is in some measure connected w ith essential od, and in plants is often united with it, as w ell as with other principles. Son e vegetables, however, exude juices which concrete into a matter entirely resinous, and't is from these that the characters of the substances belonging to this genius are taken. The distinguishing properties of a resin are its existing in a solid state, being insoluble in water* but soluble in alcohol, ether, and oils ; the solution in ether or alcohol is decomposed by water; resins are in general odorous and sapid, though neither of these qualities is essential to a pure resin; they are inflammable, and burn with much smoke; at a temperature nearly that of boiling water they melt; but they cannot be volatilized without being decomposed. In close vessels the products of their decomposition by heat, are water, empyreumatic acetic acid, an empyreumatic oil and a residuum of charcoal, indicating carbon, hydrogen, and oxygen, to be their ultimate principles. At the common temperature of the atmosphere, they do not combine with oxygen ; neither are they acted on by w ater; the solutions of them in alcohol are therefore employed under the form of varnishes, to preserve other bodies from alteration by exposure to the air. They are dissolved by the fixed alkalis, likewise by some of the acids, especially the acetic : the stronger acids decompose them. The existence of resin in a vegetable is discovered by OF PHARMACEUTIC CHEMISTRY. 45 infusing it in alcohol: this dissolves the resin if any is present, and it can then be precipitated from the solution by the addition of water. The method of estimating the quantity of resin in any vegetable, is by ascertaining the increase of weight which alcohol acquires from it by digestion, or the alcohol may be evaporated by a moderate heat, and the resin obtained pure. Resins are in general more active than gums, with respect to their medicinal powers. The purest resins are indeed nearly inert, but there are many vegetable substarces which act powerfully on the system, th t appear to consist principally of resinous matter and it is in this resinous part that their powers reside. The proper solvent or menstruum of resin is alcohol; by this it can be extracted from some of the other constituent parts of vegetables, though there are others which are soluble in the same fluid, and therefore it is difficult to obtain the resin pure. Though resin is insoluble by itself in water, yet part of it can be taken up, and kept suspended by the medium of gum. These two principles are often naturally mixed in vegetables, forming what are named Gum-resins, and some of the most active articles of the Materia Medica are natural compositions of this kind Their properties are derived from the two principles of which they consist: thus, they are only partially soluble either in water or in alcohol; they are soluble in alkaline liquors; they are not fusible by heat, they only soften, and if the heat is raised higher are decomposed, affording a little ammonia with the usual products, probably derived from the gum they contain. The proportions of gum and resin, thus mixed, are in different substances of this family very various; but they are generally such, that a mixture of equal parts of water and alcohol dissolves the gum-resin. This is their proper solvent; it also dissolves some other vegetable principles, particularly extract, and hence it is the menstruum most generally used in Pharmacy to extract the active matter of vegetables. OF THE GENERAL PRINCIPLES 46 Balsams are resinous juices, with an intermixture generally of essential oil, and containing always a portion of the acid named Benzoic Acid They are usually thick and tenacious, becoming by age concrete. They are odorous and pungent, principally from the essential oil they contain. A principle of considerable importance in its pharmaceutic relations, is what has been named by the French Chemists, by whom its characters were first established, Extract, or Extractive Matter, and which is supposed to constitute the active matter of many vegetables. Its leading character is that it is soluble equally in pure water and in alcohol; and hence a solution of it in the one fluid is not precipitated by the addition of another. By this property it is distinguished both from gum and resin, the one being insoluble in water, the other in alcohol. The compound of the two, or gum-resin, is indeed partly soluble in either of these fluids, but it never is completely so, since if it contain as much gum as renders it soluble in water, it is only partially dissolved by alcohol; and if it consist principally of resin, so as to be completely dissolved by alcohol, it is imperfectly dissolved by water. If a gum-resin be digested with alcohol, the tincture it affords is decomposed by water, and, vice versa, its watery solution is decomposed by alcohol. There is another character by which extractive matter is distinguished, that of suffering decomposition when exposed in a humid state to the atmospheric air; this takes place even at natural temperatures, and with still more rapidity when the temperature is raised, as when the extractive matter is boiled in water: it then becomes insoluble and comparatively inert. This change, Fourcroy ascribed to the fixation of oxygen. According to T. Saussure, oxygen is indeed absorbed, but carbonic acid is at the same time formed ; he supposes, too, that part of the oxygen and hydrogen of the extractive matter combine and form water, and that the inert insoluble precipitate has therefore an increased proportion of OF PHARMACEUTIC CHEMISTRY. 47 carbon. It is from this cause apparently that the medicinal powers of many vegetables are injured by decoction in water with the admission of air, and not, as was at one time believed, from the dissipation of any volatile active principles ; many plants indeed which sustain injury from this operation, containing no such principles. By oxymuriatic acicl, extract is converted into a concrete substance of a yellow colour, insoluble in water, probably from a similar change. It exerts affinities to argil and to metallic oxides. By heat it is decomposed, affording empyreumatic oil and acid, with a portion of ammonia; and in this, as well as in its spontaneous decomposition, when the re-action of its elements is favoured by humidity, it leaves as a residuum carbonates of potash and lime. This principle is supposed to be the base of what are named the Extracts of Plants ; preparations formed by boiling vegetables in water, and evaporating the clear liquor to a thick consistence. As procured in this way, it must generally have an intermixture, greater or less, ofthose principles, which are soluble in water ; and from being so liable to decomposition, it must be injured during the evaporation. It is the basis, too, though in a similar state of intermixture and partial decomposition, of what are named the inspissated juices of plants. It exists also in the seeds, leaves, bark, and wood. Though the characters of this principle appear to be distinctive, there is still some ambiguity with regard to it, particularly from the circumstance, that these characters are not uniform; a principle existing in some vegetables which has some of these distinctive properties without the others; as, for example, in Peruvian bark, the active matter of which is rendered inert and insoluble by decoction in water; and so far has one of the peculiar properties of extract; while it has not the other, that of equal solubility in alcohol and water, but is more soluble in the former than in the latter. Nor is there any certainty that this extractive matter has been obtained pure and insulated; and it is therefore pos- 48 OF THE GENERAL PRINCIPLES sible that it may consist of some of the other principles in a stale of mixture, their properties being modified by their reciprocal action. Tavnin. The important medicinal property of astrigenry, appeared from some chemical facts to be dependent in vegetable substances on a peculiar principle, as it is discoverable in them by a chemical test; that of striking a deep purple colour with the salts of iron. This effect is exhibited by all the powerful vegetable astringents, and in a degree nearly proportional to their astringency. A peculiar acid having been discovered to exist in these astringents, afterwards named Gallic Acid, it was supposed to be the principle on which rhis property depends. But subsequent experiments have proved, that it resides in a principle of a different nature, which being the agem chiefly concerned in the operation of tanning, has received the name of Tan or Tannin. This principle exists in all the powerful vegetable astringents; it is extracted by maceration with water, and is detected in the infusion by a peculiar test, that of the animal principle denominated Gelatin. If a solution of gelatin is added to the infusion, it becomes turbid, aud a precipitate is thrown down composed of the tannin and gelatin in combination. We have no very perfect process for obtaining tannin in an. insulated state ; but the most simple is precipitating it from the infusion of a vegetable astringent by lime water, and afterwards submitting the compound of lime and tannin which is formed, to the action of dilute muriatic acid, which abstracts the lime, and leaves the tannin. Tannin evaporated from its solution is loose and friable, having a resinous fracture, of a brown colour, a peculiar odour, and a taste rough and bitter. It is soluble in water, either eld or warm, and in alcohol not very highly rectified. It appears to suffer decomposition from exposure to the air in a humid state. By the aeids, it is precipitated from its watery solution, and by some of them is decomposed. It unites with the alkalis, form- OF PHARMACEUTIC CHEMISTRY. 49 ing soluble compounds ; with the earths it forms compounds of sparing solubility ; it exerts affinities to the metallic oxides, and it is principally from its action that infusions of vegetable astringents produce dark coloured precipitates with metallic salts. Exposed to heat, it affords an acid liquid, an oil, and a considerable quantity of carbonic acid, leaving a spongy charcoal. Its action on animal gelatin is its most important property in relation to the object of the present outline, as on this probably depends its astringent power; it combines with it, forming an insoluble precipitate, whence it corrugates and renders more dense the animal fibre of which gelatin constitutes a principle part. It exists in all the powerful vegetable astringents, mixed with extractive matter, mucilage gallic acid, and other principles. It has also been established, that it is capable of being artificially formed, principally by the action of sulphuric and nitric acids on vegetable products which abound in carbonaceous matter. Vegetable Acids. The acid found in the juices and other parts of plants, is not always the same. Not less than seven acids, different from each other, are of vegetable origin,—the Gallic, Oxalic, Malic, Citric, Tartaric, Benzoic, and Acetic. To these may be added the Prussic, though this is more peculiarly formed from animal matter. Gallic Acid. The existence of this acid in some of the more powerful astringents, particularly in the gall nut, can be discovered by their watery infusion reddening the infusion of litmus. If the concentrated infusion be left exposed to the air for some months, this acid is deposited in the of a crystalline deposite, mixed with mucous flakes, from which it may be purified. It may also be obta ned by sublimation from the gall nut, or even by distillation with water, though it is doubtful whether, as procured, by these or other processes, it is altogether free from tannin ; that by sublimation appears to be more so. By cristallization it is obtained in slender prisms of a white colour; its taste is Vol. I. 8 50 OF THE GENERAL PRINCIPLES sour, and it reddens the vegetable colours ; it is soluble in 24 parts of cold, and in less than 2 parts of boiling water; it is also soluble in alcohol. It suffers decomposition from heat, and the process indicates a large quantity of carbon in its composition. It combines with the alkalis and earths, and also with the metallic oxides, forming with the latter in general coloured precipitates ; it is doubtful, however, whether these colours are not in a great measure derived from the tannin adhering to it. Gallic acid was at one time supposed to be the principle of astringency, from being contained in the vegetable astringents, and giving a dark colour with the salts, of iron, the chemical test by which astringency appears to be indicated. It is doubtful, however, as has just been remarked, whether this latter property does not arise from the presence of tannin; the colour it does produce is less deep too, than that which the infusion itself strikes; and the acid in its insulated state has no astringency. Tannin is much rather to be considered as the astringent principle, and it exists accordingly in some of the more powerful vegetable astringents, as in catechu or kino, with scarcely any trace of gallic acid. Malic Acid is contained in the juice of unripe apples and other fruits; it is uncrystallizable, forming when evaporated merely a thick liquor, which, if the heat be continued, becomes charred. By this and by the properties of the salts which it forms, it is principally distinguished from the other vegetable acids. By nitric acid it is converted into oxalic acid. Citric Acid often accompanies the malic acid in the juices of unripe fruits, and it exists in a purer form in the juice of the lemon and lime from which it is extracted ; the mucilaginous matter of the juice beingseparated by alcohol. It crystallizes in rhomboidal prisms; which, when it is pure are colourless ; its taste is extremely sour ; it is abundantly soluble in water; its solution undergoes spontaneous decomposition, but the crystallized salt can be preserved without injury. The more powerful acids decompose it, converting it principally into acetic acid. OF PHARMACEUTIC CHEMISTRY. . 51 Oxalic Acid exists in the juice of the sorrel (oxalis acetosella) and some other plants, combined with a portion of potash, not sufficient to neutralize it. It can also be artificially formed by subjecting fecula, gum, or sugar to the action of nitric acid. It crystallizes in slender prisms of a white colour; its taste is extremely sour; it is soluble in twice its weight of cold water, and an equal weight of boiling water; it is also soluble in alcohol. It is decomposed by the more powerful acids: in its decomposition by heat, it affords little empyreumatic oil; hence it appears to contain a small proportion of hydrogen ; and as some of the other vegetable acids are converted into it by the action of nitric acid, there is probably a large proportion of oxygen in its composition.— The test by which it is peculiarly distinguished, is the insoluble precipitate it forms with lime, which it attracts from all the other acids. Tartaric Acid. This acid, as it exists in vegetables, is usually combined with potash, in such a proportion, however, as to leave an excess of acid in the combination. This forms the super-tartrate of potash which is contained in a number of vegetable fruits. It is deposited from the juice of the grape in its conversion into wine, or in the slow fermentation which the wine suffers when kept. The acid procured from this salt is in tabular crystals, transparent; they are very soluble in water, the solution when concentrated being of an oily consistence. It is decomposed by heat, affording a large quantity of liquid acid little changed, with much carbonic acid gas. By nitric acid repeatedly distilled from it, it is converted into oxalic acid. This acid is an important one in pharmacy, from the numerous combinations of it applied to medicinal use. Benzoic Acid is obtained from the vegetable balsams, generally by the process of sublimation. It condenses in slender crystals, white and brilliant. It is volatile, as this mode of preparation shows; its vapour is also inflammable ; it is very sparingly soluble in cold water, but abundantly in hot water; the solution on cool- OF THE GENERAL PRINCIPLES 52 ing depositing nearly the whole of the acid in prismatic crystals: it is also soluble in alcohol, from which it is precipitated by cold water; it is pungent, but not very acid to the taste; in its usual state its smell is fragrant, especially when it is heated: but this odour has been supposed to arise from a minute portion of the oil of the balsam adhering to it; as by repeated combinations with an alkaline base, and precipitation by an acid, it is obtained at length inodorous. It is not easily decomposed by the action of the more powerful acids. Decomposed by heat, it affords a larger quantity of empyreumatic oil than any other vegetable acid, whence hydrogen is supposed to predominate in its composition. Acetic Acid. This acid has been considered as more exclusively the product of fermentation; it exists likewise, however, ready formed in the sap of the vine, and, combined with alkalis and earths, very generally indeed in the sap of plants. In its pure and concentrated state, in which state it can be procured only by artificial processes, it is a very powerful acid, highly pungent and fragrant, volatile and inflammable, and is distinguished by the peculiar action it exerts on some of the other proximate principles of plants,—essential oil, resin, gum-resin, camphor, gluten, and caoutchouc, which it dissolves without decomposing. Hence, even in its diluted state, under the form of distilled vinegar, it is sometimes used as a solvent in pharmaceutic processes ; though it is seldom that it can be employed to advantage, as it is liable to modify the powers of the substances it dissolves. Prussic Acio. The substance to which this name is given, is formed from some varieties of animal matter by artificial processes. It had often been remarked, that its odour is similar to that of the peach blossom, and that the same odour is perceptible in the distilled water of the cherry laurel, and of the bitter almond. This led to experiments on these; whence the fact, rather singular, has been discovered, that all of them contain this acid. The fact, not less important, has been OF PHARMACEUTIC CHEMISTRY. 53 established, that the narcotic property possessed by these distilled waters depends on the prussic acid. In its insulated state, this substance is volatile, so that it escapes even from its watery solution under exposure to the air. It has no sensible sourness, and does not redden even the more delicate vegetable colours. The character of acidity is therefore given to it, rather from its powers in the combinations it forms, especially those with the metallic oxides, than from its properties in its insulated state. Several of the vegetable acids, particularly the citric, malic, and tartaric, exist together in the same vegetable, and in proportions varying according to the stage of vegetation, whence it is probable that they are mutually convertible. They seldom exist pure, but generally in combination with saccharine, mucilaginous, and extractive matter. Combined with alkaline and earthy bases, they form what have been named the essential salts of plants. The last of the proper proximate principles of vegetables is Lignin, or wood ; the substance which, composing the vessels of the plant, is the basis through which the other principles are diffused, or to which they are attached, and which is the basis therefore of all the parts of vegetables, with the exception of their secreted juices. It is, when freed from the principles diffused through it, insipid, inert, and insoluble, liable in a humid state to slow spontaneous decomposition, inflammable, and decomposed by heat, leaving a large residuum of charcoal, which indicates carbon to be its predominant ingredient, whence probably arises its solidity and comparative chemical inactivity. Being insoluble in water, or in alcohol, it forms the greater part of the residuum, when the active matter of vegetable substances has been abstracted by maceration in these solvents. Besides the principles which can thus be obtained in a distinct form from vegetables by analysis, there are others of a more subtle nature, which have been supposed to exist in vegetable matter, though scarcely 54 OF THE GENERAL PRINCIPLES capable of being exhibited in an insulated state ; such are the Aroma or Spiritus Rector of plants, the Acrid Principle, the Bitter Principle, and the Narcotic Principle. The Aroma is the principle in which the odour of plants has been supposed to reside. This quality is generally found in the essential oil; but there are some vegetables, having a strong odour, which yield little or no essential oil, such as the jessamine, the violet, or the rose; or, if this oil be procured from them in small quantity, it has not that strength of odour which, considering their fragrance and the smallness of its quantity, might be expected from them. They exhale this odour, however, when exposed to the air; it is at length dissipated, or it is communicated to water by distillation at a very gentle heat. Hence it has been concluded, that a principle more subtle than the essential oil exists in which the odour resides, and that it is even this principle which communicates odour to the oil. These facts, however, are altogether inconclusive. The property of odour may belong to any of the proximate principles of vegetables, and does belong to principles of very different kinds ; it exists in other bodies in which we cannot suppose the existence of any common principle; nor is their any reason to assume the existence of such a principle in plants ; and all the facts, which have been considered as favourable to the opinion, are accounted for on the supposition that essential oil is the more common pri nciple of odour, and is capable of being volatallized in small quantity at a low temperature, and of thus being diffused through the atmosphere, or communicated to water. The existence of an Acrid Principle has been inferred from an acrimony residing in some plants, which they lose on drying, while their other active powers remain ; and from this acrimony being in some cases transferred to water or alcohol by distillation. It is not very certain, however, if this quality is not in such cases connected with some of the known proximate principles: OF PHARMACEUTIC CHEMISTRY. 55 nor has this acrid principle, if it do exist, been obtained so as to submit it to chemical examination. A principle has been supposed to exist in some of the vegetable bitters in which their bitterness resides. It is obvious, however, that the quality of bitterness may belong to any of the known proximate principles; and the qualities which have been assigned to this principle as it exists in some vegetables, particularly in gentian or quassia, such as equal solubility in water and in alcohol, and being precipitated by certain re-agents, rather prove it in these cases at least to be a variety of extractive matter. A Narcotic Principle has been supposed to exist, from the narcotic power of some vegetables being impaired by age, without any apparent loss of matter, and from its being rendered inert by decoction, though no volatile matter is collected possessed of the quality. But such facts are rather favourable to the conclusion, that the loss of power is owing to chemical changes in one or other of the known principles, probably the extract, in which the narcotic quality may be supposed to reside. In submitting opium to analysis, it has been affirmed, that a crystalline matter is obtained, which proves narcotic, and has been supposed to be the principle on which that quality possessed by the opium depends. But it does not, admitting its existence, appear to be possessed of the narcotic property in that high degree we should expect, were it the principle on w T hich that property is dependent, nor is there any proof that it exists in any other narcotic. The existence of all these principles, therefore, is extremely problematical; and the qualities assigned to them may, with much more probability, be referred to modifications of composition in the known principles, which are probably too subtle to be ever determined by chemical analysis. OF THE GENERAL PRINCIPLES 56 Alcohol, and the Ethers formed from it by the action of acids, cannot be regarded as vegetable products ; yet they have a relation to these, as their chemical constitution is similar, and they cannnot be formed but by changes produced in vegetable matter. As important medicinal, and pharmaceutic agents, they are entitled to notice. Alcohol is formed by the process of fermentation from saccharine matter, or from fecula, the latter being previouly subjected, partially at least, to the operation of malting, by which it is in fact converted into the former. The fermented liquor being distilled, affords the alcohol formed during the process, diluted with water, and with some impregnation of odour from the fermented substance. From this pure alcohol is procured by repeated distillation, the abstraction of the water from it being aided by the action of potash, or rather sub-carbonate of potash. Alcohol is a colourless transparent fluid, having a specific gravity, according to its state of concentration, from 0,835 to 0,800 ; it is fragrant and pungent, and in its action on the living system possesses a high degree of stimulant and narcotic power; it is volatile, and inflammable, affording, during its combustion, no products but water and carbonic acid, the quantity of water exceeding even the weight of the alcohol. It therefore, much hydrogen in its composition, with which carbon is combined, and perhaps also a portion of oxygen. It combines with water in every proportion, and, in consequence of the affinity between these fluids, they mutually precipitate substances which either has dissolved, that are insoluble in the other. It is decomposed by the acids, affording, as the principal product, the different ethers. As a pharmaceutic agent, it is of much importance from the solvent power it exerts on a number of the vegetable proximate principles,—essential oil, camphor, extract and others, and by its property too of counteracting the spontaneous changes to which vegetable matter is liable. OF PHARMACEUTIC CHEMISTRY. 57 Ether. The name Ether is given to a peculiar product obtained by the action of the more powerful acids on alcohol, the product differing in its properties according to the acid employed in its formation, but in general being extremely light, volatile, and inflammable. Sulphuric ether, formed by the action of sulphuric acid on alcohol, has a specific gravity not greater, when it is pure, than 0.716; it is so volatile as to evaporate rapidly at the common temperature of the atmosphere ; in burning it affords water and carbonic acid : its odour is fragrant and penetrating ; its taste pungent; it is soluble in water only in limited proportion, about one part in ten. It exerts on the vegetable principles the same solvent action nearly as alcohol, except on extract which it has been said to precipitate,—an effect, however, I have not been able to obtain from it. Nitric ether is equally light and even more volatile ; it is inflammable; it is soluble in water in limited quantity, but combines with alcohol in every proportion : its odour is strong and penetrating. Muriatic ether is more volatile than either, existing in the state of gas, under the atmospheric pressure, at 60 deg. at 50 it becomes liquid, and its specific gravity is not less than 0.874 ; it is transparent, colourless, odorous, and pungent. Acetic ether is moderately light, volatile, and inflammable, soluble in water in limited quantity, and has an odour ethereal, but approaching also to that of vinegar. All these ethers appear to differ from alcohol, principally in having a larger proportion of hydrogen in their composition, to which probably their greater levity and volatility are to be ascribed; and they generally contain a portion of the acid by the action of which they have been formed, which, in some of them at least, appears essential to their chemical constitution. Having pointed out the distinguishing properties, and the general pharmaceutic relations of the jfrojumuie Vol. I. 9 58 OF THE GENERAL PRINCIPLES Principles of Vegetables, it may be proposed as a question important in relation to the object of the present outline, Do these principles usually exist in the vegetable in a state of chemical combination, whence some modification of their powers might result, or are they more generally mechanically mixed ? The latter appears to be generally the case. These principles can often be observed existing apart from each other, and even placed in separate vesicles; they can in many cases be separated by mechanical means; and even where they are more intimately mixed, that change of properties does not take place, which we must have expected were they chemically united, the virtues of each principle being discernible in the entire mixture, weakened, but not changed. It seems to follow, therefore, that the virtues of vegetable substances do not depend on chemical combinations of their proximate principles, but rather on the peculiar ultimate composition, of one or other of these principles. Hence also it is evident, that in separating the proximate principles of any vegetable, we cannot expect to alter or improve its virtues, farther than in concentrating them by a separation from what is inert, or in separating principles which are possessed of different or even opposite powers. The attainment even of these ends, however, is, in innumerable cases, of importance in their exhibition as medicines. From this enumeration of the Proximate Principles of Vegetables, we may perceive the reasons for those pharmaceutic processes to which plants are usually subjected. Vegetable matter being liable to decomposition when in a humid state, from the re-action of its elements and their entering into new combinations, exsiccation is an operation to which they are generally subjected, to preserve them without injury. It is performed either by the action of a current of air, or by exposure to heat, care being taken that the heat shall not be such as to dissipate any of their volatile principles, or cause any chemical change. By Infusion in water, the fluid is impregnated with OF PHARMACEUTIC CHEMISTRY. 59 the gum, sugar, extract, tannin, saline substances, part of the essential oil, and part also of the resinous princir pie. The aroma of the plant is generally first taken up : by longer infusion the water is loaded with the colouring, astringent, and gummy parts: these are also most abundantly dissolved when the temperature is high.— Hence an infusion differs according as the water has stood longer or shorter on the materials, and according as it has been promoted or not by heat. An infusion made in the cold is in general more grateful, while one made with heat, or by keeping the fluid long upon the materials, is more strongly impregnated with active matter. By Decoction or boiling, the solvent power of the water is still farther increased; and hence the liquor always appears darker coloured, and is, in fact, more loaded with the principles of the vegetable which it can hold dissolved. The volatile parts, however, particularly the essential oil, are entirely dissipated; and therefore it is an improper process for those vegetables whose virtues depend, wholly or partially, on these parts. Even the fixed principles of vegetables, at least some of them,, are injured Jby long decoction. The extractive matter, for instance, gradually absorbs oxygen from the atmosphere, and is converted into a substance nearly insipid and inert. Opium, Peruvian bark, and many other vegetables, are injured in this manner by decoction, especially if the atmospheric air is freely admitted ; and these two circumstances, the dissipation of the volatile matter, and the oxygenation of the extractive, considerably limit the application of this process. It is still used, however, with advantage, to extract the mucilaginous parts of vegetables, their bitterness, and several others of their peculiar qualities. Alcohol may be applied to vegetables to extract those principles which are not soluble in water. It dissolves entirely their essential oil, camphor, and resin ; and as these are often the parts on which the virtues of vege- 60 OF THE GENERAL PRINCIPLES tables depend, these solutions, or Tinctures as they are termed, are often active preparations. Equal parts of alcohol and water, in general, extract still more completely the active matter of plants, as we thus obtain a solution of all those substances which are separately soluble in either of these fluids. When by the action of one or both of these fluids, we obtain a solution of the active principles of a vegetable, the solution may be evaporated to the consistence of a thick tenacious mass. This forms what is termed an extract: it is named an Aqueous Extract when obtained from the aqueous infusion or decoction of a plant, and Spiritous when alcohol has been the solvent. The design of this preparation is to obtain the active matter of the vegetable in a small bulk, and in such a state that it may be preserved a long time without suffering any alteration. It is evident, that it is a process which can be properly applied to such plants only as have their virtues dependent on some of their fixed princ iples, and even these are often injured by the heat applied, and the free access of the atmospheric air. Distillation is another process applied to vegetable substances, by which we obtain some of their active principles, particularly their essential oil. If the vegetable matter be heated with a large portion of water, the oil is volatilized with the aqueous vapour: it separates from the water on being allowed to remain at rest; a part of it, however, is also dissolved, and communicates to the water a considerable degree of flavour, and often also of pungency. This forms what are named Distilled Waters. If alcohol is used instead of water, the essen- tial oil is completely dissolved in it, and we thus obtain what are termed Distilled Spirits. By such processes we extract the active matter of vegetables from the inert matter with which it is more or less mixed, and are enabled to administer many remedies under a variety of forms, suited to particular circumstances. A single example will show the utility of investigations of this kind, respecting the component €>F PHARMACEUTIC CHEMISTRY. 61 principles of vegetable products, and their relations to the more important chemical agents. Peruvian bark is one of the most important remedies in the Materia Medica. Practitioners have not always found it practicable to exhibit it in substance with advantage, as where the stomach is uncommonly irritable, or where from the nature of the disease, it is necessary to give it in large doses, frequently repeated, it is apt to occasion sic kness and other uneasy sensations, and even to be rejected by vomiting. Such inconveniences are attempted to be obviated, by giving it in the different forms of infusion, decoction, tincture or extract, as any of these may be, best suited to the case. Our knowledge of its constituent parts can only lead us to the proper application of these processes. From an accurate analysis of this bark, it has been proved that seven parts out of eight consist of woody fibre, or of a matter inert and insoluble, which cannot act on the system, and which affects the stomach only by its weight and insolubility. The remaining eighth part is that in which the activity of the medicine resides: it is therefore evident that if this be extracted, without injuring its activity, the medicine could be exhibited with much more advantage. This is in part accomplished by the preparations of it that have been mentioned ; but even these do not convey it in all its force. If one ounce of the bark be infused or boiled in a certain quantity of water, the infusion or decoction is not nearly equal in efficacy to the whole quantity of bark operated on. It is therefore evident, that during either of these operations, the active matter of the bark has not been entirely extracted, or has suffered some change. And here chemistry lends her assistance, and *till farther elucidates the peculiar nature of this substance, and the changes produced in it by these processes. It has been proved by experiment, that the matter on which the power of the bark depends, has a strong attraction for oxvgen at a temperature moderately increased ; that during the infusion, and particularly during the decoction of that drug, this active matter absorbs oxygen from the atmosphere, and OF THE GENERAL PRINCIPLES 62 is converted into a substance insipid and inert. This leads to the improvement of the preparations of this medicine; and experiments instituted for the purpose have accordingly proved, that, while by long boiling the virtues of the bark are nearly totally detroyed, they are fully extracted by a few minutes' decoction in covered vessels. The same investigations have pointed out the nature of the action of some other substances on bark, formerly not well understood. Thus, it has been found by experience, that the alkalis, and more partial Si irly magnesia, enable Water to extract the virtues of bark, more completely by infusion,—a circumstance elucidated by the fact since discovered, that the extractive matter of the bark, to which its activity is owing, combines with facility with these substances and forms soluble compounds. Similar examples might be given from several other important vegetable remedies, which would sufficiently prove the utility to be derived from the analysis of the substances belonging to the vegetable kingdom, and that indeed researches of this kind are absolutely necessary for their proper preparation as medicines. The account of the analysis of animal substances, and of their proximate principles, would, to the same extent at least, be foreign to the objects of this sketch, as so few of these substances are employed in medicine ; and of those which are used, the composition and consequently the pharmacuetic treatment, are in a great measure peculiar to each. Their general chemical characters are similar to those of vegetable principles. —Composed of a few ultimate elements, the differences in their properties arise in a great measure from the different proportions, or the different modes in which these are combined. And these elements having powerful reciprocal attractions, and being disposed to enter into combinations almost indefinitely diversified with regard to these circumstances, these substances are extremely susceptible of decomposition, from the re-action of their elements, favoured try OF PHARMACEUTIC CHEMISTRY. 63 humidity, by the action of the air, or by elevation of temperature. They are even more liable to this than vegetable substances; for their elements existing in simultaneous combination- are more numerous, their affinities are therefore more nicely adjusted, and of course the equilibrium is more easily subverted. Along with carbon, hydrogen, and oxygen, which are the chief constituent principles of vegetable matter, nitrogen, and frequently sulphur and phosphorus, enter into the composition of animal substances. Hence, when decomposed by heat, they afford products composed of these, of which ammonia is always the principal; and the re-action of these principles, and the evolution of the products arising from this, seem principally to form the series of changes which constitute putrefaction, the species of spontaneous decomposition to which animal matter is more peculiarly subject. Like vegetable substances, the animal products consist of various proximate principles, and some analogy may be traced between several of the vegetable and animal proximate principles. Animal fat has a strict connection in properties and composition with fixed oil; animal mucus resembles vegetable mucilage ; fecula has a similar relation to gelatin ; vegetable and animal gluten are nearly if not entirely the same ; a substance similar to saccharine matter exists in milk, and in some of the other animal secretions: in the bile is found a principle strictly analogous to resin; and benzoic, oxalic, and acetic acids are common to both. Hence, generally speaking,the few animal substances belonging to the Materia Medica are acted on by the usual solvents in nearly the same manner as vegetable substances, and are submitted to similar pharmaceutic processes. The result of these are similar officinal preparations. Thus by the action of alcohol, the active matter of musk, castor, and cantharides is extracted, and tinctures of these are employed. In other cases water is the proper solvent, particularly of those which consist of gelatin ; but such solutions being very liable to decomposition, must always be of extemporaneous preparation. 64 OF THE GENERAL PRINCIPLES CHAPTER II. OF THE PHARMACEUTICAL OPERATIONS TO WHICH THE ARTICLES 5 OF THE MATERIA MEDICA ARE SUBJECTED. Natural substances, it has been remarked, are not always obtained in that state in which they are best adapted to exhibition as remedies. They are subjected, therefore to various processes, with the view of preserving them, or of preparing them for use; and to complete this statement of the Principles of Pharmaceutic Chemistry, the nature of these is to be pointed out. These processes, or at least the greater number, and the most important of them, are chemical, and are dependent therefore on the agenciesof those general forces whence chemical changes arise ; they are indeed little more than applications of these, under peculiar regulations adapted to different substances. The general facts, therefore, connected with the operation of these forces, are first to be stated, in so far as they have any relation to the present subject. The force principally productive of chemical action, is that species of a ! traction exerted between the particles of bodies, which brings them into intimate union. If two substances of different kinds be placed in contact, and with that degree of fluidity which admits of the particles of the one moving to those of the other, it often happens that they unite together, and form a substance in which neither can be any longer recognised, and which is homogeneous, and in general possessed of new properties. This constitutes what, in the language of chemistry, is named combination, and is conceived to arise from an attraction exerted between the particles of the one body to those of the other. It is this which is denominated Chemical Attraction or Affinity, and OF PHARMACEUTIC CHEMISTRY. 65 which is distinguished from the other species of attraction by the phenomena to which it gives rise, or by the laws it obeys,—from the attraction of gravitation, by not being exerted at sensible distances, or on masses of matter, but only at insensible distances, and on the minute particles of bodies, —from the attraction of aggregation, by being exerted between particles of different kinds, and forming a substance with new properties, while that force operates on particles of a similar nature, and of course unites them into an aggregate in which the same essential properties exist. It is possible that these forces, though thus distinguished, may be the result of the same power modified by the circumstances under which it acts. The substance formed by chemical combination is named a compound. The substances united are the constituent or component parts or principles of the compound. When these are separated, the process is named decomposition. The most minute parts into which a body can be resolved without decomposition, are named its integrant parts; and it is between these that the force of aggregation is conceived to be exerted. Chemical attraction is exerted between the constituent parts. *- . . . ..i.i't The most important phenomenon attending chemical combination is a change of properties. In general the form, density, colour, taste, and other sensible qualities, as well as the fusibility, volatility, tendency to combination, and other chemical properties in the compound, are more or less different from what they are in either of its constituent parts, and frequently indeed they are whollv dissimilar. There are cases too, however, where the change is less considerable, as is exemplified in several of the operations of Pharmacy,—the solution of the vegetable proximate principles in water or in alcohol, or the solution of salts in water, in which the body acquires merely the liquid form, with perhaps a slight change of density, but in which no important property is changed, nor any new one acquired. Vol. I 10 66 OF THE GENERAL PRINCIPLES Chemical attraction is not an invariable force exerted by every body to every other, and always with the same degree of strength. Between many substances it does not sensibly operate, though this perhaps may be owing to the predominance of external circumstances, by which its operation is influenced, rather than to the absence of all mutual attraction. It is exerted too by each body towards others, with different degrees of strength. It is not limited in its action to two bodies, but is frequently exerted at the same time between three, four, or a greater number, so as to unite them in one combination. Such compounds are named Ternary, &c. according to the number of their constituent principles ; they are abundant among the productions of nature, and Gan be formed also by the arrangements of art. This force is exerted too, so as to combine bodies in more than one proportion; and, from the union of two substances in different proportions, compounds are formed frequently as dissimilar in their properties as if they were composed of principles totally different. In some cases, the combination is unlimited with regard to proportions ; in others, it is fixed to two or three relative quantities, and there are examples where it can be established in only one proportion. The opinion has been maintained, and is probably just, that the tendency of chemical attraction is to unite bodies indefinitely with regard to proportion, and that determinate proportions are established only by the operation of external forces. The compounds formed by the exertion of chemical attraction have apparently the same relation to this power as simple bodies have : they have a similar tendency to combination, unite in different proportions, and with different degrees of force ; and all these combinations are accompanied by the same phenomena, and appear to observe the same laws. It has been supposed, however, that when compound substances combine together, the combination is the result, not of the mutual attraction between the integrant particles of these com- OF PHARMACEUTIC CHEMISTRY. 67 pounds, but of the affinities of their ultimate elements modified by the condition in which they exist. In all cases, attraction is much modified, and its results determined by circumstances foreign to the attractive force itself. The operation of these circumstances has been established with more precision by the labours of Berthollet, and been proved to be more important than w T as formerly believed. They require, therefore, more distinct enumeration, especially as some of them give rise to important results in the processes of Pharmacy. 1st. Quantity of matter influences affinity, an increase in the relative quantity of one body with regard to another enabling it to act with more force; or, as the law has been stated, " every substance having a tendency to " enter into combination, acts in the ratio of its affinity " and its quantity." Hence an effect can be produced from the mutual action of two bodies, when one is in a certain relative proportion to the other, which will not be obtained when the proportion is changed,—a circumstance of much importance in Pharmacy, requiring, in particular, attention towards insuring the uniform strength of active preparations; and of much influence too on the results of chemical decomposition, rendering it frequently partial, where it was supposed to be complete. 2d. Cohesion, or the state of a body with regard to the aggregation of its integrant particles, must obviously modify the chemical action of another body upon it, by opposing a resistance which must be overcome before the union of their particles can be effected ; hence the cause, that two solid bodies seldom act chemically on each other, and that fluidity promotes chemical action, feut besides this obvious effect, cohesion, even when it has been overcome, still modifies the exertion of chemical attraction, by resuming its force whenever the force of that attraction is diminished, and thus sometimes giving rise to new combinations ; and sometimes too, when suddenly established in consequence of the OF THE GENERAL PRINCIPLES 68 affinities becoming effective, it determines the proportions in which bodies combine, by insulating the compound at a certain stage of the combination. It is thus the most powerful cause in placing limits to the exertion of chemical attraction. Insolubility is merely the result of the force of cohesion, in relation to the liquid which is the medium of chemical action, and its action is of course similar; and great Density, or specific gravity, so far as it influences attraction, operates in nearly the same manner, counteracting it, by withdrawing the substances between which it is to be exerted from the sphere of mutual action. 3d. Elasticity, or that property of bodies arising from repulsion between their particles, and present to any extent only in those existing in the aeriform state, opposes the exertion of chemical attraction, by enlarging the distances at which these particles are placed. Hence aerial fluids combine in general with difficulty; and hence too, a compound which contains an ingredient which, when insulated, assumes the aerial state, is more easy of decomposition, and the decomposition is more complete, than a compound, the ingredients of which are fixed ; for the tendency to elasticity in the volatile ingredient counteracts the mutual affinity ; and when, by the application of heat, or the operation of a superior attraction, any portion of it is displaced, by assuming the elastic form it is withdrawn from the sphere of action, and ceases to oppose any obstacle by its affinity or quantity to the progress of the decomposition. Elasticity too, by counteracting attraction, places limits to the proportions in which bodies combine. 4th. The last circumstance influencing attraction is Temperature, or the state of a body with regard to heat or cold, which sometimes favours, and in other cases subverts combination. The cause of temperature is a peculiar subtle power or principle, (in modern chemical language denominated Caloric) capable of being communicated to bodies, and of being in part at least withdrawn from them. Its immediate tendency is to OF PHARMACEUTIC CHEMISTRY. 69 establish a repulsion between their particles ; hence it gives rise to expansion or enlargement of volume, greater in each body according to the quantity of caloric introduced. This progressive augmentation of distance, at which the particles are placed by its action, is accompanied with a proportional diminution in the force of cohesion; if carried, therefore, to a certain extent, that force is so far modified, that the particles become capable of moving easily with regard to each other, —a state which constitutes fluidity; and, if the communication of caloric be continued, the expansion still continuing, the particles are at length placed at such distances, that the attraction is entirely overcome, and they repel each other, —a state which constitutes the aerial or gaseous form. The operation of caloric in influencing chemical attraction, appears to depend on the changes it occasions in the cohesion and elasticity of bodies, —favour- combination by diminishing cohesion, counteracting or subverting it by communicating or increasing elasticity ; these effects too being often produced together, and modifying each other. From the differences of the forces of affinity among bodies, or still more perhaps from the operation of those circumstances by which affinity is modified, its power is often suspended or overcome, and substances which have been combined are separated. This forms what in Chemistry is named Decomposition, and it presents results equally important with those from combination. The decomposition may be simple, that is, a compound may be resolved into its constituent parts, each of which is insulated. This is in general effected by the agency of heat. Within a certain range of temperature, the affinity which has combined two bodies continues to operate; but when the temperature is raised, and when the bodies differ in their volatility, or the tendency they have to assume the elastic form, the elasticity of the more volatile one is so far favoured by the elevated temperature, that the mutual affinity is overcome, and it is disengaged. It is generally obtained pure ; but the fixed QF THE GENERAL PRINCIPLES 70 substance, from the influence of quantity on chemical attraction, frequently retains a portion of the other combined with it. Decomposition is more complicated when it is produced by the introduction of a third substance, which exerts an attraction to one of the ingredients of a compound. When this is effective, the body added combines with this ingredient forming a new compound, and it is only the other ingredient of the original compound that is obtained insulated. A case still more complicated is, where two compound substances are brought to act on each other, and the principles of the one exert affinities to those of the other; so that an interchange takes place, the two compounds are decomposed, and two new ones are formed. Both these kinds of decomposition are likewise materially modified by the state with regard to temperature. The former case used to be named by chemists single elective attraction ; the latter double elective attraction ; and both were considered as the results of the relative forces of attraction among the bodies concerned. But there is reason to believe, that they arise from the operation of cohesion, elasticity, and the other forces that influence attraction ; and that but for the operation of these forces, three or more bodies presented to each other would enter into simultaneous union, instead of passing into binary combinations. Galvanism, as well as caloric, influences chemical affinity, and, by the attractive as well as by the repulsive force it exerts, is even more powerful in producing decomposition. It scarcely admits, however, of being applied to any pharmaceutic process. The operations of Pharmacy are generally dependent on these chemical powers ; they consist of arrangements of circumstances, with the view either of promoting their exertion, or of obtaining the products of chemical action. Some preliminary operations are frequently had recourse to, of a mechanical nature, to diminish the cohesion of bodies, or enlarge their surface. - Such are Pul- ©F PHARMACEUTIC CHEMISTRY. 71 verization, Trituration, Levigation, Granulation, &c. Pulverization is the term employed where solid bodies are reduced to powder by beating: Trituration that where the same effect is produced by continued rubbing. Levigation denotes the operation where the powder is rubbed to a still greater fineness, the rubbing being facilitated by the interposition of a fluid, in which the solid is not soluble. As by any of these operations, the powder must consist of particles of unequal size, the finer are separated from the coarser by sifting or washing. Sifting is passing the powder over a sieve, the interstices of which are so minute, as to allow only the finer particles to pass. Washing or Elutriation, is an operation performed only on substances which are not soluble in water. The powder is diffused through a quantity of that fluid, and the mixture is allowed to remain at rest. The coarser particles quickly subside, and the finer remain suspended. It is then decanted off, the powder is allowed to subside, and is afterwards dried.— These methods of reducing bodies to powder, can be applied to very few of the metals, their force of cohesion being too strong. They are mechanically divided by rasping, or by being beat into leaves, or they are granulated —an operation performed by melting the metal, and when it is cooled down as far as it can be, without becoming solid, pouring it into water: it passes to the solid state, assuming the granular form. In Pharmacy, these operations are sometimes of importance, besides merely promoting chemical combination, as there are some medicines which act with more certainty, and even with more efficacy, when finely levigated, than when given in a coarse powder. As means of promoting chemical combination, it is evident, that they can act only indirectly ; the bodies being far from being reduced to their minute particles, between which only chemical attraction is exerted. They are therefore employed, merely as preliminary to those operations in which such a division is obtained by chemical means. OF THE GENERAL PRINCIPLES 72 Of these, the first is Solution. By this is understood that operation in which a solid body combines with a fluid in such a manner that the compound retains the fluid form, and is transparent. Transp irency is the test of perfect solution. When the specific gravity of a soiid body differs not greatly from that of a fluid, it may be diffused through it, but the mixture is more or less opaque; and on being kept for some time at rest, the heavier body subsides ; while in solution the particles of the solid are permanently suspended by the state of combination in which they exist, and are so minute as not to impair the transparency of the liquid. The liquid has, in this case, been regarded as the body exerting the active power, and has been named the Solvent or Menstruum ; the solid is considered as the body dissolved. The attraction, however, whence the solution proceeds, is reciprocal, and the form generally proceeds from the larger quantity of the liquid employed, and from the absence of cohesion being more favourable to the combination proceeding to a greater extent. In general, the solution of a solid in a liquid can be effected only in a certain quantity. This limitation of solutionis named Saturation; and when the point is reached, the liquid is said to be saturated with the solid. As the fluid approaches to saturation, the solution proceeds more slowly. When a fluid is saturated with one body, this does not prevent its dissolving a portion of another ; and in this way three, four, or five bod es may be retained in solution at the same time by one fluid. In these cases, the fluid does not dissolve so large a proportion of any of these substances, as if it had been perfectly pure, though sometimes the whole proportion of solid matter dissolved is increased from the mutual affinities the bodies exert. Neither is the solvent power always thus limited, there being many cases where a solid may be dissolved in a fluid to any extent. Gum or Sugar, for example, will dissolve in water, and form a perfect solution in every proportion. An increase of temperature, in general, favours solu- OF PHARMACEUTIC CHEMISTRY. 73 tion, the solution proceeding more rapidly at a high than at a low temperature ; and in those cases in which a certain quantity only of the solid can be combined with the fluid, a larger quantity is taken «p when the temperature is increased. The quantity dissolved is not in every case promoted alike by an increase of temperature ; water, for example, having its solvent power, with regard to nitre, greatly increased by augmentation of temperature, while sea salt is dissolved in nearly as great a quantity by water at a low as at a high temperature. This difference in these salts, and in many others, depends on the difference in the degree of their fusibility by heat; those which are most easily fused having their solubility in water most largely increased by increase of temperature. All these facts, indeed, with regard to solution, are explained, by considering this operation as depend.ng on chemical affinity overcoming cohesion in the body dissolved. Agitation favours solution, by bringing successively the different parts of the liquid into contact with the solid, and thus preventing the diminished effect which arises from the approach to saturation in the portion immediately covering the solid. The mechanical division of a solid too, is favourable to its solution, principally by enlarging the surface which is acted on. Solution is an operation frequently had recourse to in pharmaceutical chemistry, the active principles of many bodies being dissolved by their proper solvents. Salts are dissolved in water, as are also gum, extract, and other vegetable products. Products of a different kind, as resin, camphor, and essential oils, are dissolved in alcohol and wine; and metals are rendered soluble and active by the different acids. Solutions in water, alcohol, or wine, possess the sensible qualities and medical virtues of the substance dissolved. Acid and alkaline liquors change the properties of the bodies which they dissolve. In Pharmacy, the operation receives different appellations, according to the nature of the solvent, of the substance dissolved, and of the manner in which it is performed. Vol. I. 11 OF THE GENERAL PRINCIPLES 74 When a fluid is poured on any vegetable matter, so as to dissolve only some of its principles, the operation is named Extraction, and the part dissolved is said to be extracted. If it is*performed without heat it is termed Maceration; if with a moderate heat, Digestion; if the fluid is poured boiling hot on the substance, and they are kept in a covered vessel till cold, this is denominated Infusion. Decoction is the term given to the operation when the substances are boiled together. It is evident, that these are all instances of solution, varied only by particular circumstances; and I have already stated, under the analysis of the vegetable part of the Materia Medica, the advantages belonging to each. Lixiviation is the term applied to solution performed on saline substances where the soluble matter is separated by the action of the solvent, from other substances that are insoluble ; and the solution obtained in this case is named a Ley. The other principal method by which that fluiditynecessary to chemical action is communicated, is Fusion. It requires, merely with regard to each substance, the necessary degree of heat; and where this is high, it is performed usually in crucibles of earthen ware, or sometimes of black lead, or on a large scale in iron pots. Chemical combination is frequently promoted by an elevation of temperature, though the heat may not be so high as to produce fusion, but only to diminish cohesion to a certain extent. Calcination, as it used to be named, or metallic oxidation, is an example of this ; a metal being heated to a high temperature, so as to enable it to combine with the oxygen of the air. Deflagration is a similar operation, an inflammable or metallic substance being exposed to a red heat in mixture with nitre: the acid of the nitre yields its oxygen ; which being thus afforded in large" quantity and nearly pure, the oxidation takes place with rapidity, and generally to its maximum. When chemical action has been exerted, other opera- OF PHARMACEUTIC CHEMISTRY. 75 tions are sometimes required to obtain the product, or sometimes this product is formed and collected in the operation itself. By or dissipating a liquid by the application of heat, a solid substance which has been dissolved in it is recovered, and this operation is one frequently performed in Pharmacy. When performed on a small scale, vessels of glass, or of earthen ware, are generally employed, and the heat is applied either by the medium of sand, or if it is required to be more moderate, the vessel is placed over water which is kept boil ng, forming what is named the Water Bath, or Balneum Marice. When performed on a larger scale, shallow iron pots or leaden troughs are used, to which the fire is directly applied ; and experiments have shown that the operation is conducted more economically when the liquor is kept boiling strongly, than when it is evaporated more slowly by a more gentle heat. There is, on the other hand, how ever, some loss, from part of the dissolved substance being carried off when the heat is high, by its affinity to the liquid evaporating; and in many cases in Pharmacy, particularly in the evaporation of vegetable infusions or tinctures, the flavour, and even the more active qualities of the dissolved substance, are liable to be injured, especially towards the end of the operation, by a strong heat. When the object is to obtain the volatile matter by evaporation, the process is of course conducted in close vessels adapted to condense the vapour and collect the liquid. This forms the operation of Distillation, which, with regard to different substances, requires to be conducted in various modes. When a volatile principle is to be obtained from vegetable substances by this process, the difficulty is to apply the heat sufficiently without raising it too high. The mode generally employed is to heat the vegetable matter w r ith water, and the distillation is then usually performed in the common still. At the heat of boiling water, the essential oil of plants, which is the chief vo- OF THE GENERAL PRINCIPLES 76 latile principle they contain, is volatilized ; it rises with the watery vapour ; is condensed ; if little wa ter has been employed, the greater part of the oil is obtained apart; if much has been used, it retains it dissolved, acquiring taste and flavour, and thus forming the distilled water of plants. If alcohol, pure or diluted, has been the medium of distillation, it always retains the oil in solution, and forms what are named Distilled Spirits. The still in which the operation is performed with these views is of copper or iron; it consists of a body and head, the former designed to contain the materials, and to w hich the fire is applied, the latter to receive the vapour; there issues from a tube, which is connected with a spiral tube, placed in a vessel, named the refrigerate ry, filled with ccld water. The vapour, in its progress through the tube, is condensed, and the liquid drops from the extremity of it. When metallic matter would be acted on, by the materials or the product of distillation, vessels of glass or earthen ware are employed ; the retort, which is gei < rallv used being connected with a single receiver, or vt ith a range of receivers, acco rding as the vapour is more or less easily condensed ; or, if the product is a permanently elastic fluid, which cannot he condensed but by passing it through w r ater, a series of bottles connected by tubes, on the principle of Woolfe's apparatus, is used, When the product obtained by distillation is not perfectly pure, it can be frequently purified by a second distillation; the process is then named heclijcation : when it is freed from any superflous water combined with it, the operation is named Dephleymalion or Concentral ion. When the product of volatilization is condensed, not in the liquid, but the solid form, the process is named Su blimation, and the product a Sublimate. As the condensation takes place with much more facility, a more sin pie apparatus is employed, consisting usually of a conical bottle or flask with around bottom thin and equal, named a Cucurbit, in which the materials are OF PHARMACEUTIC CHEMISTRY. 77 contained, heat being applied by the medium of a sand bath. The vapour condenses in the upper part of the flask, forming a cake, which adheres to it, the orifice being Hghtly closed to prevent any part from being lost; or a globular head, with a groove at its under edge, and a tube to convey off any liquid that may be condensed, (a Capital as it is named,) being applied. When a solid substance is thrown down from a liquid by chemical action, it forms the operation of Precipitation, and the matter thrown down is named a Precipitate. Frequently the substance precipitated is one which had been dissolved in the liquid, and which is separated by a substance added, combining with the liquid, and weakening its attraction to the one which it held in solution. Or sometimes it arises from a compound being formed by the union of one body with another, which is insoluble in the liquid that is the medium of action. The precipitate is allowed to subside, is usually washed with water, and is dried. From the law of chemical attraction, that quantity influences the force of affinity, it often happens that the precipitate either retains in combination a portion of the substance by which it had been dissolved, or attracts a portion of the substance by which it is thrown down, and this sometimes proves a source of impurity, or of peculiar powers in medicinal preparations. When a substance, in passing to the solid state, assumes a regular geometric form, the process is named Crystallization, and these figured masses are denominated Crystals. Their forms are various, though nearly constant with regard to each substance ; they are usually transparent, hard, and have a regular internal structure. The crystallization may happen in two ways, from a state of solution. If a saturated solution has been prepared with the aid of heat, the increased quantity of the solid, which the heat has enabled the liquid to dissolve, separates as the temperature falls ; and the attraction of cohesion being thus slowly exerted between the particles, unites them so as to form crystals. Or, if a 78 OF THE GENERAL PRINCIPLES portion of the solvent be withdrawn by evaporation, and especially by slow evaporation, the particles of the solid unite slowly, and with a similar result. In both these kinds of crystallization from a watery solution, the crystallized substance always retains a quantity of water, and frequently even a considerable proportion, in its composition. It is essential to the constitution of the crystal, its transparency, structure and form, and is hence named the Water of Crystallization. Some crystals lose it from mere exposure to the air, when they are said to effloresce ; others attract water, and become humid, or deliquesce. Crystallization is promoted by the mechanical action of the air; likewise by affording a nucleus, whence it may commence, and especially a crystal of the substance dissolved; and with regard to a few substances, their affinity to the solvent requires to be diminished by the addition of another substance to enable them to crystallize. In Pharmacy, crystallization is of importance, by enabling us to obtain substances, especially those belonging to the class of salts, in a pure form ; different salts, even when present in the same solution, being thus separated by their different tendencies to crystallization, according as they are more or less soluble is the solvent, or have their solubility more, or less promoted by heat, and each salt, when it does crystallize, being in general pure. These are the principal operations of Pharmacy. Connected with this subject, there remain to be noticed the weights and measures which are usually employed. The division according to what is named Trov weight, is that ordered in the Pharmacopoeias. Its parts, with the symbols by which they are denoted, and their relative proportions, are represented in the following table : A pound (libra,) Jfo g f 12 ounces. An ounce (unica,) v'* / 8 drachms. A drachm (drachma,) S l°i 3 scruples. A scruple (scrupulus,) 3 ) 3 (. 20 grains (grana) gr. OF PHARMACEUTIC CHEMISTRY. 79 Measures have been subdivided in a similar manner, being made to correspond to the specific gravity of water. As the specific gravities of liquids vary, however, considerably, a source of error is introduced in applying the standard measure to different liquids, unless the due allowance be made for the difference in specific gravity. This it is to be presumed will often be neglected, and hence the Edinburgh College have rejected the use of measures, and given the proportions of every liquid by weight. The use of measures, however, in apportioning liquids, being more easy and convenient, will probably always be retained ; and the London College have therefore, in the late edition of their Pharmacopoeia, sanctioned their use. They adopt measures subdivided from the wine gallon, as represented with their symbols in the following table: A gallon (congius), V= C 8 P mts * A pint (octarius), 0 f'§ ' * 16 fluidounces. A tiuidounce (fluiduncia), I S \ 8 fluidrachms. A fluidrachrn (ftuidrachma,) f3 ) 8 v. 60 minims, (minima) m This last measure is one newly introduced. In apportioning liquids into very small quantities, the quantity has been usually estimated by drops (gutta, gtt.) allowed to fall from t he edge of the mouth of a bottle ; but the size of the drop is liable to vary much, not only according to the mobility and specific gravity of the liquid, a circumstance of little importance, since with regard to each substance it remains the same, but also according to the thickness of the edge and degree of inclination. The London College have therefore substituted this division of minims, which are measured in a slender graduated glass tube. The measures of a table and of a tea-spoonful are sometimes used in extemporaneous prescription, and, though not very accurate, may be admitted where a small difference in the dose is not important. The one is understood to be equal to half an ounce by measure, the other to about one drachm. 80 PART II. OF MATERIA MEDICA. MATERIA MF.DICA, in the extensive signification which has sometimes been attached to the term, comfirizes the history both of Aliments and of Medicines, t is used, however, and more correctly, as opposed to the [Materia Alimentaria ; and in this limited sense may be defined that department of Medicine, which describes the properties, and investigates the effects on the living system of those substances, which are employed as remedies against disease, —substances which are not necessary to the immediate support of the functions of life, to repair the waste of the body, or furnish matter whence its secretions are derived, but are more peculiarly adapted to excite actions in the system, or produce changes, with a view to the removal of morbid states. It includes the history of these substances, independent of the preparations to which they are subjected to fit them for administration, this belonging to the department of Pharmacy. 81 CHAPTER I. preliminary observations on the objects of study in the history of the articles of the materia medica, and on their classification. The subjects of enquiry, in the study of the articles of the Materia Medica, may be comprised under their Natural History, their Chemical History, and what may be more strictly denominated their Medical History. The utility of Natural History in furnishing appropriate characters by which the productions of nature may be distinguished from each other, is abundantly obvious; and its application to the articles of the Materia Medica is under this point of view indispensable. From want of such characters, the remedies described by the ancient physicians cannot now in many cases be accurately ascertained: did we not possess them, our observations would in the progress of time be liable to the same inconvenience ; and the accurate distinctions which the methods of natural history afford, are at present necessary to discriminate between substances which have a near resemblance to each other, or to describe with accuracy the remedies employed in different countries. This subject has likewise been considered under a higher point ot view. From attention to the characters of the articles of the Materia Medica, as they are objects of natural history, it has been supposed, that assistance may be derived in the investigation of their virtues; these being sometimes indicated by their natural affinities. In artificial systems of classification, the discriminating characters are taken from one or two remarkable properties possessed by a certain number of bodies, and these are arranged together, though they may differ widely in.the general assemblage of their, Vol. I. 12 82 MATERIA MEDICA. qualities. In the natural method, the arrangement is founded on the occurrence of a number of characters taken from what is essential to the substance ; the gradations of nature are observed, and those bodies are arranged together, which in their general appearance, nature, and qualities, have a close resemblance. It is the prosecution of this natural method that has been supposed useful in ascertaining the medicinal virtues of the productions of nature, —a supposition not unreasonable, since, where there exists a natural resemblance in structures and qualities, it might be inferred that there may be a resemblance in medicinal powers. In the vegetable kingdom especially, this natural affinity has been industriously traced and applied to this purpose. Those vegetables which agree in their general structure, habit, and appearance, are thrown into what are named Natural Orders or Families ; and experience has shown, that the individuals composing many of these natural orders, have a remarkable similarity in their effects on the system. In the subdivisions of the order, this analogy is not less striking, the different species having in general similar virtues. If therefore, a new species of any of these genera be discovered, the discoverer may infer with some probability, a priori, that it will possess virtues similar to those of the genus to which it belongs. This criterion of the virtues of medicines, though undoubtedly so far just, is however liable to many exceptions. Many natural orders are composed of vegetables, which, though they agree in structure, have the most various and opposite qualities; and even in those in which there is in general the greatest similarity, there are found wide differences in the properties of many plants arranged under them. Even in the subdivision of the genus, there is often a remarkable difference in the properties of the species; and what sufficiently points out the deficiency of this method, different parts of the same plants have often opposite powers. Yet it is to be admitted, that with all these exceptions, Na- PRELIMINARY OBSERVATIONS. 83 turalists have often been led by such analogies to just conclusions respecting the virtues of plants; and in studying the vegetable part of the Materia Medica, attention is undoubtedly due to these natural distinctions. A part of the Natural History of Medicines, of still more importance than their generic and specific characters, is the accurate description of their sensible qualities. Such descriptions afford the most obvious method of distinguishing them, and in many cases also the most easy and certain criterion of their purity and perfection. A knowledge of these qualities is not less necessary, as it leads to their proper administration, since, from the peculiar qualities of taste, 'favour, specific gravity, or consistence in any substance, one form may be better adapted to its exhibition than another. It has also been imagined, that the sensible qualities of medicines, particularly their taste and smell, lead to indications of their peculiar powers, and experience to a certain extent confirms this supposition. In the vegetable kingdom especially, it has been found, that substances which are insipid and inodorous rarely possess any considerable medicinal virtues, and a number of such substances have justly been discarded from practice from attention to this circumstance: their insipidity having led to suspicion of their activity, and occasioned a more strict examination of the evidence on which their supposed virtues were said to be established. On the other hand, plants possessing much odour or taste, are in general active remedies; and those which resemble each other in these qualities, have often the same general medicinal powers : astringency is indicated by a styptic taste, bitters are tonics, aromatics are stimulating, and fcetids, narcotic. There are, however, so many causes of obscurity and error in these indications, that they do not admit of very extensive accurate application. The different tastes and odours are so little reducible to precise definition MATERIA MEDICA. 84 or description, that few general rules can be formed from them ; and even to the few that have been delivered on this subject, there are many exceptions. The most active vegetable substances too, have not these properties more peculiar than many others comparatively inert, and hence it is not often that much assistance can be derived from this criterion of the virtues of plants. The Chemical History of the articles of the Materia Medica forms another important general object of investigation. The opinion seems to have been early adopted by those who cultivated chemistry with a view to its application to medicine, that those substances which agree in their action on the system' must be composed of the same principles, and that?'therefore chemical analysis may be a successful method of investigating their medical virtues—an opinion not altogether unreasonable. The properties of any compound depend on its peculiar chemical composition ; they originate from that composition, and are altered by every variation which it suffers. The medicinal powers of such substances must, in common with their other qualities, depend on the same cause ; and it is not unreasonable to presume, that where similar powers exist, they arise from similarity of composition, either with regard to the constituent principles, or to the peculiar mode in which these are united. Confiding in the justness of these conclusions, the chemists, about the beginning of the 17th century, bestowed much labour on the analysis of the different vegetables used in medicine. Above 500 plants were analyzed ; but had even the analysis been performed with all those essential precautions, which it was impossible that the state of Chemistry at that period could have furnished, the nature of it was such, that it could lead to no useful information. The plants subjected to analysis were exposed to heat, and the products collected ; but as these products do not pre-exist in the vegetable, but are formed by new combinations of its ele- PRELIMINARY OBSERVATIONS. 85 merits, and as these elements are in all vegetables nearly the same, no connection can be traced between them and the qualities of the substances from which they are obtained. It was found accordingly, that the most inert and the most poisonous vegetable afforded the same products ; and if the experiment were now repeated with all the advantages of the rigorous methods of Modern Chemistry, no information useful to the physician would be obtained. Similar proximate principles of different plants, though possessed of different medicinal powers, would give similar results ; or if any difference were observed, it would be impossible to connect this with the difference in their powers. Nor can we expect from the chemistry, at least of our times, to be able to discover on what chemical principle, or what peculiarity of combination, the peculiar powers of any active vegetable productions depend ; for although these, in common with other qualities, may arise from chemical composition, yet the varieties of combination from which they may be supposed to derive their origin, are too minute to be detected by our modes of analysis. The pretensions of modern chemistry, as applied to Materia Medica, are therefore more humble, but they are more just. By discovering those proximate principles of vegetables in which their active powers reside, and enabling us to separate them from each other, or from other inert and noxious matter with which they may be mixed, it allows us to apply them with much more advantage : it determines how far in every case such operations are useful: whether the principles thus operated on are altered by these operations, and by what means such alterations, if injurious, may be obviated. Similar advantages are obtained from its application to the few products of the animal kingdom that are employed in medicine ; and those belonging to the mineral kingdom can be used with much more advantage and discrimination, when their nature has been ascertained by analysis, than when we are left to collect their virtues from experience. 86 MATERIA MEDICA. By the combinations which chemistry regulates, it furnishes us with many remedies which owe to these combinations their sole power, and which are equally active with many of those afforded by nature. Lastly, it has taught us the proper methods of administering these substances. Many of them exert a mutual action, combine together, or decompose each other; and were such facts which Chemistry discovers not precisely known, important errors would frequently be committed in their mixture and administration. The last object in the study of the Materia Medica, that to which the others are merely subservient, is their Medical History, or the investigation of the virtues and uses of remedies. This comprehends several important subjects of inquiry. There belongs to it the consideration of the action of those substances on the system in its healthy state ; since, when this is ascertained, it leads to their application to the treatment of disease. It may in general be affirmed, though the principle is not without exception, that substances which do not act sensibly on the body in ahealthy state, will not prove active remedies : and that, on the contrary, every substance which is capable of producing any important change in the system, must be more or less extensively adapted to the removal of morbid affections. Another subject of inquiry, scarcely less important, relates to the mode in which remedies act, and by which they produce their peculiar effects. It is not sufficient merely to have ascertained by the evidence of experience, the virtues of certain remedies in certain cases. It is of importance, farther, to arrange the facts thus collected ; to institute some comparison between remedies possessed of nearly the same general power, and, so far as can be done, to investigate their mode of operation, with the view of extending their application, and of administering them with more precision. Lastly, with regard to what may be more strictly termed the medicinal powers of remedies, there are a number of subjects of consideration of importance. It PRELIMINARY OBSERVATIONS. 87 is necessary to take notice of the applications for which each individual article is distinguished ; the forms of disease to which it is adapted ; the circumstances that may influence its operation, or in certain cases render its exhibition doubtful or improper ; the cautions necessary in its use ; the dose in which it is given ; the usual and proper forms of exhibition ; and the effects of the combinations of remedies with each other. These observations point out the subjects to which the attention is principally to be directed in the study of the articles of the Materia Medica. Very different systems have been followed, according to which these substances are arranged. The two which are least exceptionable, and which are possessed of undoubted advantages, are that founded on their natural distinctions, and that resting on their medicinal powers. The latter ground of classification appears more systematic, and more conformable to the object of the studyitself, than any other. These substances are subjects of inquiry, merely as possessed of certain medicinal properties : they ought to be classed, therefore, it might be concluded, on principles conformable to this : and by founding the classification on this basis, some important advantages are obtained : we are enabled to place together the remedies which are possessed of similar virtues, to deliver the theory of their operation, to compare the powers of the individual substances arranged under the class ; and by a reference to this generalization, to point out more distinctly their degrees of activity, and the peculiarities which may attend the operation of each. The principal difficulty which attends it, is one arising perhaps from our imperfect knowledge of the laws of the animal economy, and of the operation of remedies, in consequence of which we cannot always assign their primary action, but are often under the necessity of arranging them from their more obvious, though secondary effects. Hence, as many substances are capable of producing various effects of this kind, and are actually employed in medicine to obtain this diversity of effect. MATERIA MEDICA. 88 the same substance frequently requires to be considered liuder different classes, and under each its history is incomplete* It m ay be capable of acting, for example, as an emetic, as a cathartic, and as a diuretic : did we know precisely the primary operation of it, whence these effects arise, this might serve as the basis of its classification ; but this being unknown, and the classification being established on these secondary operations, it must necessarily be placed under each of these classes, aud uuder each, its history is imperfect; as it must be limited to the operation which g. ves the character of the class un )er which it is arranged. I n a course of Lectures this is extremely inconvenient; the history of almost every important article of the Materia Medica being placed under different divisions, frequently remote from each other, and no distinct and complete view of it being delivered. But in a treatise, to the different parts of whh h it is easy to refer, this is of less imp< stance, and is more than compensated for, by the other advantages of which this method of classification is possessed. A nd wdien the merits of two modes of classification are so nearly balanced, it is even of importance to exhibit the subjects connected with them, under the points of view which each mode more peculiarly affords. It is this classification, therefore, which is followed in the present work. 89 CHAPTER II. GENERAL VIEW OF THE OPERATIONS OF MEDICINES, AND OF THEIR CLASSIFICATION FOUNDED ON THESE OPERATIONS. The advantages of an arrangement of the articles of the Materia Medica, founded on their medicinal operations, I have stated under the preceding observations; and in endeavouring to exhibit this branch of medicine, strictly as a science, it is that undoubtedly which ought to be followed. The difficulty of constructing such an arrangement, has at the same time always been experienced. No subject is involved in greater obscurity, than what relates to the action of substances on the living system. Their effects are not always easily appreciated with accuracy, especially in a state of disease, and our knowledge of the laws of their action is extremely imperfect. When we attempt, therefore, to class them according to these actions, we can scarcely form an arrangement strictly, just and systematic, but are forced to admit of some deviations, and to be guided not unfrequently by imperfect analogies. The difficulty of constructing a classification of medicines from their operations, will be apparent from the failure even of Cullen, when he attempted the execution of this task; for there can now be little hesitation in affirming, that the one he has given, rests on principles nearly altogether false. The following table represents this classification: Vol. I 13 90 GENERAL VIEW OF THE Simplicia. Astringentia. Toniva. Emollientia. Erodentia. Viva. Stimulantia. Sedan tia. Narcofica. Refrigerantidi Antispasmodica. SOLIDA. MEDIC AMENTA AGUNT IN Immutantia. S Fluid itatein. Attenuantia. Inspissania* Mistucam. Atrimoniam corrigentia. In get!ere. Demulcentia. In specie. Anlacida. Antalkalina. Anttseplica* Fluida. Evacuantia Errhina. Stalogoga. Expectorarttia. Emettcct. Cathartica. Diuretica. Diaphorefica. Menagoga. Now, without examining it minutely, it may be remarked, that the basis ofthisclassi cation, the assumption that some medicines act exclusively on the solids, others on the fluids of the body, is incorrect; for, with the exception of two or three classes, the action of tho OPER ATIONS OF MEDICINES. 91 whole is on the living solids. Thus, emetics, cathartics, diuretics, diaphoretics, emmenagogues, expectorants, sialogogues, and errhines, produce their effects, unquestionably by no operation on the fluids which they evacuate, but by exciting a particular organ to action. The distinction is equally nugatory in the greater number of cases between the action of medicines on the simple solids and on the living solids. It cannot be doubted, but that tonics produce their effects in removing debility, not as the hypothesis of Cullen assumes, by any action on the inanimate fibre of the body, giving it densitv or tone, but by their operation on the vital powers of the system. Nor can the effects of astringents be ascribed entirely to their corrugating quality. In this arrangement too, are placed classes of medicines which have probably no real existence, the action ascribed to them being merely hypothetical. We may be allowed to question the existence of attenuants and inspissan'S —medicines which render the fluids of the body more thin, or which produce the opposite effect. Nor is there any reason to believe in the reality of antisep ics. The process of putrefaction probably never takes pi ice in the living body ; and if it did, we know of no medicines by which it could be retarded or counteracted. * In the system of Brown, which succeeded that of Cullen, more just views were of the relations of external agents to the living system, and of the laws regulating their action. The operations of medicines, however, are even in this svstem imperfectly explained principally, perhaps, from its author having surveyed all the parts of his subject with those views of generalization which nearly preclude all minute distinctions. Medicines he supposed to operate merely as other external agents, by exciting to action either the general * That putrefaction does not take place in the living body has been most conclusively proven by a series of well conducted experiments. Vid. Seybert's Inaugural Thesis. University, Penn. 17J3. 92 GENERAL VIEW OF THE system, or the particular organs on which they operate ; and to differ from each other in little more than in the degree in which they exert this stimulating power. They have, farther than this, no specific properties, but are adapted to the removal of morbid affections, merely by producing excitement, partial or general, with certain degrees of rapidity or force. This proposition is far from beins* just, at least in an unlimited sense. Medicines, and even external agents, in general unquestionably differ, not only in degree, but in kind of action. Every substance applied to the organs of sense, gives a different sensation, not referrable to the mere force of the impression, but which must be attributed to some essential varieties in the modes of action of the agents themselves. Every organ is excited to its usual or healthy action only by its appropriate stimulant. It is the same with regard to medicines, or differences in the kind of action they exert are not less conspicuous. Opium and mercury both excite the actions of the system, and so far a. NARCOTICS. 129 teric paroxyism, opium is often employed with advantage, either introduced into the stomach, or given under the form of enema. In purely spasmodic asthma, the paroxysm is shortened, and even sometimes cut short by a full dose of an opiate. In colic, it relieves the violence of the pain; though its administration requires caution, where there is any tendency to an inflammatory state; and the constipation it is liable to produce requires also to be obviated. In cholera it is the principal remedy. In pyrosis, a moderate dose generally affords at least temporary relief; and it, also frequently succeeds in checking vomiting from morbid irritability of the stomach. In syphilis, opium is employed, principally with the intention of alleviating the irritation arising from the operation of mercury; for there is no sufficient evidence for the opinion, which has been advanced with regard to the anti-syphilitic power of opium alone. Considerable advantage is derived from its use in extensive venereal ulceration; as well as in the treatment of painful and irritable ulcers, not connected with a venereal taint. It is given too as a stimulant to check the progress of gangrene. In many other cases of morbid affection, opium is had recourse to merely to lessen irritation, relieve pain, or induce sleep. Asa palliative, it is indeed the most valuable article of the Materia Medica. Externally applied, opium alleviates pain and spasmodic action. Applied by friction, it thus relieves the pain of cramp, and even of tetanus ; and rubbed over the abdomen, it alleviates spasmodic pain of the stomach and intestines. It often relieves the pain of toothach. Applied under the form of enema, it is of singular efficacy in relieving tenesmus, and that painful affection of the prostate gland which is sometimes the consequence of the discharge in gonorrhoea having been suddenly checked; and also that irritable state of the neck of the bladder, which renders the discharge of urine Vol. I. 17 130 JNARCOTICS. painful. It is used under the same form in diseases where it cannot he introduced into the stomach. The dose of this narcotic is very various, according to the state of disease, and the intention with which it is administered. One grain is the medium quantity to a person unaccustomed to its use. Its power on the system soon becomes weaker; and from habitual use is so much impaired, that very large doses are required to produce its usual effects. In some diseases, too, particularly mania, tetanus and hydrophobia, it produces little sensible effect unless the dose be very large. In the last disease, it has been taken to the extent of two drachms in twelve hours, without abating the violence of the symptoms. Lastly 7 , the opeiation of opium is much varied by idiosyncracy, the same dose producing very different effects on different individuals.* By the immoderate or long continued use of opium, the vigour of the digestive organs is impaired ; hence loss of appetite, wasting of the body, and muscular weakness; the nervous system, and even the functions of the mind, are also affected ; the patient is distressed with uneasy sensations, which are only imperfectly relieved by other stimulants, if opium is withheld, and at length fatuity and stupor are induced. When such a dose of opium is taken, as would prove fatal if its effects were not obviated, the symptoms are, insensibility, so that the patient cannot be roused by any exertion ; a pulse usually slow and full; deep and difficult breathing, and the countenance generally somewhat flushed : this state of stupor continues sometimes *The quantity of laudanum which has sometimes been taken would be incredible, if the fact were not attested by indisputable authority. I knew in one case, a wine-glass full of it to be given, several times in the twenty-four hours, for many months in succession, to alleviate the pain from the passage of biliary calculi. In a case of Cancer of the uterus which was under the care of two highly respectable physicans of this ciiy, Drs. vlonges and La Roche, the quantity was gradually increased to three pints of laudanum, besides a considerable portion of opium, in the twenty-four hours.-—Ed. NARCOTICS. 131 with occasional convulsions, until it terminate in death. The principal remedy in such a case is the immediate exhibition of an emetic, which requires to be of the most powerful kind. Sulphate of zinc, or sulphate of copper, is generally used, dissolved in water, and introduced by a flexible tube into the stomach, the former in the dose of one scruple, the latter in a dose from five to ten grains ; and if vomiting is not soon induced, the dose is repeated. Along with this is employed free dilution with the vegetable acids, as vinegar, which is to be swallowed in as large draughts as the stomach can receive it. The powers of the stomach and of the general system may be roused and sustained by small doses of warm brandy ; coffee has been said to have been taken with advantage, and the patient ought to be kept awake, and, if possible, in a state of gentle motion, at least for some hours.* Opium is used either solid, or under the form of tincture, twenty-five drops of the tincture being equal to one grain of crude opium. It is employed in the solid state when we wish it to act slowly, or on the stomach and intestinal canal, otherwise it is more convenient in the liquid form. There are, besides, various preparations, in which it is either the principal ingredient, or modifies the power of others. Officinal Preparations. —Elect. Opiat. Pil. Opiat. Pulv. Opiat. Pulv. Ipecac, cum Opio. Tinctura Opii. Tinct. Opii Ammoniatae. Tinct. Saponis cum Opio. Troch. Glycirrhiz. cum Opio. Pharm. Ed. —Pil. Opii. cum Sapon. Pulv. Cornu Usti cum Opio. Tinct. Opii Camph. Vin. Opii. Emplast. Opii. Pharm. Lond. —Opium Purification. Extr. Opii. Syrup. Opii. Dub.f * In these cases, after a short time, the pulse becomes full and febrile, accompanied by a phrenetic state of the brain. At this stage, copious blood letting is most imperiously demanded.—Ed. t Tot tie above preparations may be added two others, which, under the denomiinat onof the Black Drop, are muchu-ed in the popular practice, and have acquired some reputation among the physicians of this city. Of my own knowledge, I can say little of this medicine. I have occasionally prescribed it, and I am inclined to believe not without advantage, in cases to which 132 NARCOTICS. The dried capsule of the poppy is sometimes employed for medicinal purposes. Its active matter is extracted by decoction with water ; this evaporated, affords an extract similar in power to opium, but weaker, or made into a syrup, by boiling with sugar, it is used as an anodyne. This syrup is a weak preparation, and is in general only given to children. One ounce of it is supposed to be equal to one grain of opium, but it is liable to be variable in strength. The dose to a child a year old is one drachm. A syrup made from opium has been supposed to be preferable, as the dose can be regulated with much more certainty, and a formula of this kind is accordingly adopted by the Dublin College; being prepared by dissolving the watery extract of opium, and forming this into a syrup, by adding the due proportion of sugar. An infusion of the capsules is used as an anodyne fomentation. Offic. Prep. —Extr. Papav. alb. Syr. Papav. somnif. Ed.-~ Decoct. Papav. Somn. Lond. laudanum did not seem to be well suited. It is however alleged by those whose experience with it is more enlarged, that it is never productive of head-ach, giddiness, nausea, and the rest of the distressing narcotic effects of opium and its ordinary preparations. The formulae are as follows: 1. Take of purified opium, five ounces. ¦ pimento and cinnamon, two drachms. —— saffron and orange peel, of each one drachm. — 1 spirit of wine rectified, one pint. Digest a week and strain the liquor through flannel, to which is to he nddcd sugar candy enough to make it pleasantly sweet. 2. Take of opium, four ounces. i— sharp vinegar or lemon juice, four pints. Digest three weeks, and then add saffron, cloves, nutmegs, and cinnamon, of each an ounce, coarsely powdered. Continue the digestion a week longer, strain through flannel, and evaporate the liquor reduced to the consistence of syrup. The dose of these preparations is about a half of that of laudanum, and it is the latter of them which is chiefly employed in Philadelphia. Neither the one nor the other is a new medicine, as similar receipts are to be found in the old writers. Vid. "The Mysteries of Opium Revealed," the first edition of Quint y's Dispensatory, &c. En. 133 NARCOTICS. HroscvAMCs Niger. Black Henbane. Pentand. Monog. Solanacece. Herba, Semen' Indigenous. The leaves of this plant, when recent, have a slightly foetid smell, and a mucilaginous taste ; when dried, they lose both taste and smell, and their narcotic power is in part impaired. The root possesses the same qualities as the leaves, and even in a more eminent degree, but is liable to be more variable in strength. The seeds also are narcotic. Henbane has an analogy to opium in its action more than any other narcotic, particularly in the power of inducing sleep. In a moderate dose, it increases at first the strength of the pulse, and occasions some sense of heat, which are followed by diminished sensibility and motion ; in some cases by thirst, sickness, stupor, and dimness of vision. In a large quantity, it occasions profound sleep, hard pulse, and sometimes delirium • and in a dose which proves fatal, its operation soon terminates in coma, with a remarkable dilatation of the pupil, distortion of the countenance, a weak tremulous pulse, and eruption of petechioe. On dissection, inflamed or gangrenous spots have been observed on the internal surface of the stomach, and the vessels on the membranes of the brain have appeared enlarged. Its baneful effects, like those of other vegetable narcotics, are best counteracted by a powerful emetic, and by drinking largely of the vegetable acids. Henbane is one of the narcotics which has been longest known to physicians, having been employed by the ancients for mitigating pain, and restraining haemorrhage. Stork of Vienna introduced it, and several other vegetable narcotics, to the notice of modern practitioners. He employed it in various spasmodic and painful diseases, as in epilepsy, hysteria, palpitation, headach, paralysis, mania, and scirrhus. It was given in the form of the inspissated juice of the fresh leaves, the dose of which is from one to two grains, which requires to be gradually increased. At present it is principally employed as a substitute for opium, where the latter, 134 NARCOTICS. from idiosyncracy, occasions any disagreeable symptom. The henbane is also free from the constipating quality of the opium. A tincture of it has been introduced into the pharmacopoeias, which affords a preparation probably more uniform in strength, than the inspissated juice. Its dose is thirty drops.* Offic. Prep. —Succ. spiss. Hyosc. N. Tinct. Hyosc. N. Ed. Lond. Dub. Atropa Belladonna. Deadly Nightshade. Pentand. Monogyn. Solanacex. Folia. Indigenous. The leaves have scarcely any smell, and only a slightly nauseous, sub-acrid taste. The berries are sweetish. Both are narcotic, as is also the root, but the leaves are preferred for medicinal use, as being more uniform in strength. In a moderate dose, belladonna occasions a sense of warmth, followed by diaphoresis, and a disposition to sleep, frequently with nausea and headach ; in large dose, symptoms of intoxication, vertigo, sickness and thirst : the pulse becomes low and feeble, the pupils are dilated, vision is impaired, and these symptoms terminate in convulsions, coma, or paralysis. On dissection, where il has proved fatal, the stomach and intestines have been found inflamed, or gangrenous, and the blood in a dissolved state. The remedies are an emetic in a sufficiently large dose, and dilution with the vegetable acids. Belladonna was first employed as an external application, in the form of fomentation, to scirrhus and cancer. It was afterwards administered internally in the same affections ; and numerous cases in which it had proved successful, were given on the authority of the German practitioners. It has been recommended too, as a remedy in extensive ulceration, in paralysis, chronic rheumatism, epilepsy, mania, and hydrophobia, but with so * The henbane is one of those plants which is cultivated in several parts of this country for medicinal purposes, and succeeds well.—-Ed. NARCOTICS. 135 little discrimination, that little reliance can be placed on the testimonies in its favour : and in modern practice, it is iittle employed. It appears to have a peculiar action on the eye; hence it has been used in amaurosis ; and from its power of causing dilatation of the pupil, when topically applied under the form of infusion, it has been used before performing the operation for cataract —a practice which is hazardous, as the pupil, though much dilated by the application, instantly contracts when the instrument is introduced.* When given internally, its dose is from one to three grains of the dried leaves, or one grain of the inspissated juice. Offic. Prep. —Succ. Spiss. Atrop. Bellad. Ed. Lond. Aconitum Napellus. Aconite, Monk's-Hood, or Wolfsbane. Polyand. Trigyn. Mullisiliqu beats in a minute, and being small and tremulous. This is accompanied with sickness, anxiety, vertigo, dimness of vision, and, in a large dose, with vomiting, syncope, coldness of the extremi ties, convulsions, and coma, with sometimes a fatal termination. Yet these effects are not uniform, but even from the same close we observe considerable diversity of operation in different individuals : thus the pulse is sometimes rendered lower, without being diminished in fullness; at other times it is rendered irregular; nor does sickness always accompany the reduction of the force of the circulation. Sometimes none of these effects, and scarcely any perceptible change in the state of the functions are immediately apparent; but if the dose be continued, they are suddenly produced. ed from it in all the cases enumerated above, and to which I may also* add, the tit; doloreux, and other anomalous affections of the nerves. The cicuta is now cultivated in this section of the United States, and is vastly superior to that which is imported from abroad.—En. NARCOTICS. 139 Effects are even observed from the operation of foxglove, apparently of a very opposite kind. While it reduces the force of the circulation, it appears to increase the action of the absorbent system, and hence proves a powerful remedy in dropsy; and Dr. Withering, by whom its powers were first particularly investigated, observed, that when given in a state of disease, it was most successful, not where there existed increased action in the system, but, on the contrary, in states of debility, where the pulse was feeble and intermitting, and the countenance pale. Other authors have remarked its stimulant operation ; and Dr. Saunders, from a series of observations and experiments, has inferred, that it always acts primarily, as a stimulant, augmenting, when given in a dose not too large, the force and frequency of the pulse, and inducing a slate of increased action ; it is only when it is accumulated by repetition, or by too large a dose, that reduction of the force of the circulation and other symptoms of diminished power are produced ; and hence, according to this view, it is strictly analogous in its operation to other narcotics.* It must be admitted, however, that it is more difficult to regulate the administration of digitalis, so as to obtain its continued stimulant operation, than it is with regard to other stimulants ; that there is a rapid transition to a state of diminished action, and that this is greater, and more permanent, compared with the primary stimulant effect, than in other stimulants even of the diffusible kind. Foxglove, producing very different effects according to the mode in which it is administered, or according to the state of the system, is employed as a remedy in different diseases. Under the present class, those applications are to be considered, which appear to be connected with its action as a narcotic. * Experiments made in this University, show that the primary operation of digitalis is slightly to increase the force and velocity of the circulation, which effect however is exceedingly transient; and is succeeded by exactly an opposite state of the pulse. Vid. Dr. Moore's Inaug. Thesis, published in 1801.—Ed. 140 NARCOTICS. On this, in part at least, has been supposed to depend the advantage derived from it as a remedy in phthisis pulmonalis. When given to that extent in which it reduces the velocity and force ofthe circulation, it proves useful, by counteracting that state of increased action which prevails in the incipient stage of the disease; and by diminishing the rapidity of the circulation through the lungs, it may facilitate the removal of the local affection. In the more advanced stages, it may operate, it has been conceived, by promoting absorption, thus removing the tuberculous affection, or withdrawing the purulent matter, before it has been rendered acrid by the action of the air. Sanguine expectations have been formed ofthe advantages to be derived from it in the treatment of phthisis, many ofthe symptoms disappearing under its use, and the progress ofthe disease appearing to be arrested. The change of organic structure is, however, so considerable, at least in the advanced stale of the disease, as scarcely to admit of a cure from the operation of any remedy; and the operation of foxglove is so much diversified, that perhaps the proper mode of administering it, has not been precisely determined, so as to admit of all the advantage being received from it that might be derived : it is difficult, as Dr. W. Hamilton has remarked, to give it so as to reduce the force of the circulation, and continue this effect without its inducing other consequences, which compel us to relinquish its use. Foxglove has been proposed as a remedy in pneumonia, from its power of reducing the force of the circulation when given in a sufficient dose, conjoined with blood-letting ; and cases have been related of the success attending the practice, while some authors have condemned it as hazardous, from the excitement it is liable to produce. On a similar principle, it has been proposed to be employed in croup. In active haemorrhage, it might be expected from the same operation, to be a remedy of much power ; and NARCOTICS. 141 according to the observations of Ferriar and others, it may be employed with signal advantage in epistaxis, haemoptysis, and menorrhagia, either alone or in combination with opium. In spasmodic asthma, the combination of it with opium has afforded much relief. In palpitation arising from intemperance, or from passions of the mind, and not connected with dyspepsia, the irregular action of the heart has been abated, and at length entirely removed by its operation. Foxglove is given in substance, or under the form of infusion, decoction, or tincture. The medium dose of the powder of the dried leaves is half a grain ; the dose of the infusion, prepared according to the formula in the Edinburgh pharmacopoeia, is half an ounce : that of the tincture is fifteen drops ; these quantities being given twice a-day. The decoction is an improper form, as being variable in strength. The tincture is the form of preparation under which it has usually been given as a narcotic: the infusion, that in which it has been employed as a diuretic. Given in substance, there is supposed to be rather more risk of its effects accumulating from repetition of the dose, so as to induce the unpleasant symptoms which arise from an over dose. To obtain the full narcotic operation of foxglove, the dose given at first requires to be gradually increased, but this increase must be made with much caution, not only from the hazard attending an over dose, but from the circumstance that the action of the remedy is for a time not apparent ; but if the dose has been too large, or repeated at intervals not sufficiently distant, it appears suddenly, and continues progressive. Hence the necessity of the practitioner's watching with the greatest attention the effects it produces.* The augmentation * This is a useful practical precept. More than once I have observed, especial 3y in dropsical effusions, that though the digitalis was given for a succession of days, in an ample dose, it produced no sensible effect, influencing neither the arterial nor 142 NARCOTICS. may proceed at the rate of one fourth of the original quantity every second day, and the dose should not be repeated more than twice, or at farthest thrice a-day, unless in acute diseases, where the effect must be more speedily obtained, and where, therefore, the augmentation must be more rapid. The increase is continued until the effect intended to be obtained from the remedy is produced, or until its operation is apparent on the system; and whenever the pulse begins to diminish in frequency or force, the increase of dose must be stopt; and if the reduction be considerable, or proceed rapidly, the administration of the remedy must be suspended, and, only after a sufficient interval, cautiously renewed. This is more especially necessary when nausea is induced, dimness of vision, vertigo, or any tendency to fainting. When these symptoms do occur, they are best obviated by small doses of stimulants, warm wine, or brandy and water, with aromatics, ether, and, as some have recommended, strong bitter infusions, small doses of opium, and a blister applied to the region ofthe stomach. The infusion of foxglove has been applied externally as an anodyne lotion to painful cutaneous eruptions, or ulceration. An ointment composed of the powder mixed with lard, has been found successful in obstinate tinea capitis. The application of foxglove, as a diuretic, will be considered under the class of diuretics. absorbent system, nor any of the functions of the animal economy, when, suddenly, t-here would come on an uncommon depression of pulse, and loss of general power, accompanied by the most copious urinary discharges. Another peculiarity in the operation of our medicine, which was first noticed in the Edinburgh Medical Journal is worthy of attention. I mean, that its action in some instances, is in no inconsiderable degree regulated by the different positions ofthe patient's body. In the case alluded to, the pulse was not at all reduced in frequency when the patient stood up, being in this posture upwards of an hundred : when he sat down, it fell to seventy-five, and when lying on his back, to forty in the minute. Cases of a similar nature, though not to the same extent, have since been recorded by Drs. Hamilton, Beddoes, and other respectable writers, so as to leave no doubt of the occasional recurrence of this anomaly.—E». NARCOTICS. 143 Offic. Prep.— Infus. Digit. P. Tinct. Digit. P. Eel Lond. Dub. Decoct. Digit. Dub. Nicotiana Tabacvm. Tobacco. Pentand. Monoyyn. Solanaecx. Folia. America. This plant, though sometimes cultivated in this country, is usually imported from America. Its leaves, which are of a large size, are of a light green colour, which they retain with little change when merely dried, but in the usual preparation to which they are subjected, they are rendered brown by the action of a little sulphate of iron. Their smell is foetid, their taste extremely bitter and acrid. They deflagrate in burning, from a quantity of nitre they contain. Their active matter is extracted both by water and by alcohol; by decoction, their powers are much impaired. The essential oil obtained from them by distillation has been said to be very highly narcotic; —an assertion which has been denied, however, by some authors. Tobacco operates as a very powerful narcotic. This is apparent, even in the common practices of smoking and chewing it, though its effects, like those of other narcotics, become less powerful from continued use. In a person unaccustomed to it, or in an over dose, it excites the most severe and permanent sickness, with vomiting, reduces the force of the circulation, and occasions extreme muscular debility, with insensibility, cold sweats, and convulsions. Taken repeatedly in small doses, it acts as a diuretic, probably by promoting absorption. As a diffusible stimulant, the smoke of tobacco, thrown info the rectum, was at one time employed in the recovery of drowned persons, a practice unquestionably hurtful, and now exploded. The same practice is still occasionally employed in ileus and incarcerated hernia; in the former disease, with the view of removing the constricted state of the intestines ; in the 144 NARCOTICS, latter, with the intention of producing that state of muscular relaxation which may favour the reduction of the protruded intestine. The practice, though not without hazard, has sometimes proved successful. The watery infusion of the strength of one drachm of the dried leaves to a pound of tepid water, is a more convenient form of employing it than the smoke, as an enema; and even the infusion of this strength has sometimes produced alarming symptoms of exhaustion. Unless it be used, however, in such a state of activity, as to produce somejlegree 0 f muscular debility, no advantage can be derived from it; and the practice is therefore only to be had recourse to, where other methods have failed. The smoke of tobacco received into the mouth, relieves the pain of toothach, either by its narcotic pow r er, or by exciting a profuse salivary discharge. The powder is in common use as an errhine. The infusion or decoction is sometimes used as an emetic, but its operation is extremely harsh, and accompanied with severe sickness. The medicated |wine is the form under which it has been used as a diuretic, in dropsy and dysuria, its dose being 30 drops. The leaves bruised or moistened, have been employed as a local application in tinea capitis, and in various cutaneous eruptions; incautiously applied, they have sometimes occasioned the effects which arise from the internal administration of tobacco in too large a dose.* Offic. Prep.—Yin. Nicot. Tab. Ph. Ed,— Infus. Nicot. Tab. Lond— Tinct.Nicot. Tab. Lond. * Applied to the region of the stomach, a cataplasm of the leaves of tobacco proves in some instances, very actively emetic, and is often in popular practice resorted to, where poisons have been swallowed. The same application is also sometimes made to expel worms, with what success, I cannot say. I have occasionally directed it in some cases of the more violent forms of mania, with a view of subduing the vigour and excitement of the patient, but I am not certain whether it has any superiority over the ordinary nauseating remedies.—Ed. 145 NARCOTICS. Ejactuca Virosa. Strong-scented Lettuce. Syngenes: Polygam. cequat Cony positce. Folia. Indigenous. The leaves of this plant have a strong foetid smell, similar to opium, and yield a white juice, in which their activity resides. Their taste is bitter and acrid. Though narcotic, they have been used principally as a diuretic in dropsy, under the form of the expressed juice inspissated. The dose of this is five or ten grains, which is gradually increased to one or two drachms in twentyfour hours. By the German practitioners, by whom principally this plant has been recommended, it has also been used as a remedy in palpitation of the heart, and in intermittent fever. Offic. Prep. —Succ. Spiss. Lact. Vir. Ed. Datura Stramonium. Thorn-Apple. Pentand. Monog. Solanacea. Herba, Indigenous. The leaves have a narcotic odour, and a bitter taste. They possess all the powers of a narcotic, produc ing, when taken in too large a quantity, vertigo, sickness, delirium, and convulsions. The usual form in which it has been given, is that of the inspissated expressed juice ofthe leaves, the dose of which is from one to three grains twice a-day, gradually increased.* * Doubts have been entertained by the botanists whether the stramonium is a native of the United States. Be this as it may, it now grows very abundantly in almost exery section of the country, and is kuown by the popular titles of Jameston weed, hen-bane, thorn-apple, stink-weed, &c. It is one of those plants which delight in a rich soil, and is most commonly to be met with on dung-hills, or other, spots of great fertility. The stramonium, in its operation on the living system, is among the most powerful articles ofthe Materia Medica. In all its properties, it is closely allied to the narcotic stimulants, and when largely taken, has produced tetanus, hydrophobia, and the wildest forms of mental derangement. Every part of the plant is active ; but the preparations employed as a medicine are an inspissated juice or extract, and the dried leaves and seed powdered. Of each of these the dose is two grains, twice a-day, to be increased till it amounts to ten. fifteen, or twenty grains. Vol. I. 19 146 NARCOTICS. Arnica Montana. Leopard's-Baue. Syngenes. Polygam. super/. Composites. FloreSf Radix. Germany' The flowers of this plant have a smell slightly foetid, and a penetrating bitter taste. In their action on the system, their direct stimulating power is very apparent The stramonium was originally introduced into the practice of physic by Dr. Stork of Vienna, to w hom we are indebted for our knowledge of the medicinal virtues of so many of the narcotic poisons. It was ui>ed by him in mania, epilepsy, and in the spasmodic and convulsive affections geneially. As is customary in the publication of a new remedy, he ascribed very valuable powers to this article and was soon imitated in its use by other practitioners, who confirmed by their testimony, the accuracy of his observations. More diversified trials however, with the stramonium, gradually diminished its reputation, till finally it ceased to attract any attention. In the late revival of the medicine by the American physicians, it has been very extensively applied to the. treatment of diseases, and particularly in this city. It has been freely prescribed in epilepsy, chorea, tetanus, and with very equivocal results. iVlore good has been done with it in some maniacal cases. 1 have sometimes found it to answer very well as a palliative in asthma, and perhaps still better, in the advanced stages of pulmonary consumption, where the cough is violent and the respiration exceedingly impeded, Che manner of using it for these purposes, is to smoke the root previously washed, dried, and bruised, in a common tobaccopipe. The stramonium, I am told, has been advantageously given in palsy and rheumatism This I can readily believe ; and also, that it will hereafter be discovered to be admirably adapted to a very large circle of cases. Of the diseases in which 1 think it promises to be of the greatest service, are some of those of the eye, as amaurosis; and, as an emi lenagogue, especially in dismenorrhoea. I have, indeed, found it beneficial in painful menstruation. Exhibited alone, or in combination with mercury, it has likewise proved in my hands a very valuable substitute for the cicuta in venereal and scrofulous ulcers of an ill condition. It corrects the state ofthe sore, and subdues the pain and irritability which are so frequentiy incident to these cases. As an external remedy the stramonium has not been neglected. The leaves steeped in brandy are recommended as an embrocation, and when boiled in milk certainly make a fomentation, which affords much relief in rheumatic and other painful swellings. There is an ointment formed of the stramonium which is of common use. It i* prepared by boiling tha bruised leaves of the plant in lard, and is employed in NARCOTICS. 147 along with their narcotic action ; they increase the force of the vascular system, and appear to communicate tone to the muscular fibre. In a larger dose, they produce vomiting and purging, sometimes followed by muscular pains, vertigo and convulsions. Along with narcotic effects, they excite vomiting and catharsis. They have been used in amaurosis, paralysis, convulsive disorders, gout, and rheumatism. The dose is five grains in substance dried, or half a drachm in infusion. The root of arnica is aromatic and tonic, and has been used as a substitute for Peruvian bark. Rhododendron Chrysanthum. Yellow-flowered Rhododendron. Decand. Monogyn. Bicornes. Folia. Siberia. The leaves of this plant are destitute of smell, but have a bitter, rough and subacrid taste, which they communicate to water by infusion or decoction. They are stimulating and narcotic, and occasion in a small dose increased vascular action; in a large dose intoxication and delirium. They have been employed principally in chronic rheumatism and gout; their power is said to be marked by a sensation of creeping in the skin and diaphoresis being induced. The form in which they have been given is decoction, 2 drachms being boiled in 10 ounces of water, and 1 or 2 ounces of the strained liquor being given twice a-day, and gradually increased. Rhus Toxicodendron. Poison Oak. Pentand. Trigyn. Dumosa. Folia North America. This plant has so much acrimony, that the touching of the leaves, or rubbing them on the skin, occasions itching, inflammation, and desquamation ; taken internally, it excites nausea, vertigo, and pain in the head. burns, in haemorrhoidal tumors, in psora, and in the herpetic eruptions. In each of these cases I have witnessed its good effects, and particularly in piles, attended with much sensibility and inflammation. For further information on this subject vid. Cooper's Inaugural Thesis, printed in 1797—Ed. 148 NARCOTICS. The dried leaves have been used in paralysis, in some cases related by Mr. Alderson, with marked advantage. The dose given was half a grain twice or thrice a-day in the form of bolus, and gradually increased to three or four grains daily. It excites a sense of heat, and irregular motions in Ihe parts affected. Humulus IiCPtrLt/s. Hop. Dioccia. Penland. Scabridx. Indigenous. This plant is cultivated in England, being used in large quantity to give a degree of bitterness to fermented malt liquors. It is a very strong bitter, accompanied with a degree of aromatic flavourand some astringency; these are extracted by water by infusion; by decoction the aromatic flavour is lost. Along with its bitterness it has a narcotic power: of this the popular remedy, sometimes successful, of a pillow of hops to procure sleep in the delirium of fever and in mania, is a proof. It aceordingly, when given internally in a full dose, reduces the frequency of the pulse and procures sleep. It has been employed as an anodyne, either in substance, in the dose of three grains, or under the form of infusion or tincture. A cataplasm or ointment prepared from it has been also used as an anodyne application to cancerous sores. It has now a place in the London pharmacopoeia. Offic. Pre^.—Tinct. Humul. Extr. Humul. Pharm. fjond. Strichnos Ndx Vomica. Vomica Nut. Pentand. Monogyn. Solanaceee. East Indies. The kernel of the fruit is the part of this plant that is powerfully narcotic ; its taste is intensely bitter; it has little or no smell, and is so hard that it cannot be reduced into powder by beating, but requires to be filed down. Its narcotic operation is well exemplified in the effects it produces when given as a poison to dogs and other animals. It occasions extreme anxiety, paralysis of the hinder extremities, convulsions and death ; and on dissection, no marks of inflammation, or local affection, are to he discovered in the stomach. 149 NARCOTICS. As a narcotic, it has scarcely been used, though it has been recommended in mania, epilepsy, and hysteria. It has been given in dysentery and intermittent fever, in a dose of 5 grains twice a-day; but the use of it is so hazardous, that it has not been established in practice, nor received into the pharmacopoeias. PituNtrs Lauro-Cerasus. Cherry-Tree Laurel. Icosand. Monog. Pomacea. Folia. Europe. The leaves of this plant have an odour slightly fragrant ; their taste is extremely bitter. They possess a highly narcotic quality, which is extracted by infusion in alcohol or water, and is even brought over by distillation in the state of an essential oil, which the water partly dissolves. And the very singular fact has been established, that the volatile principle in which the narcotic quality of this plant resides is the prussic acid. It has often been observed, that the odour of this acid is similar to that of the cherry laurel, peach blossom, and bitter almond. Bohn found, that the distilled water ofthe bitter almond contained prussic acid. Schroeder discovered it in the distilled water of the peach blossom and cherry laurel, prussiate of potash being obtained by distilling them from the alkali; and Bucholz succeeded in separating the prussic acid from the essential oil of the cherry laurel by agitation with an alkaline solution. This acid in its pure state has been further found to be highly narcotic; and the narcotic power of all these plants no doubt depends on it. The distilled water of the cherry laurel has long been known as a poison to animals, and its effects are those of a pure narcotic. It has not been employed in medicine, but a cataplasm prepared from the leaves has been used as an anodyne application to painful tumors and ulcers. 150 CHAPTER IV. OF ANTISPASMODICS. It is not easy to assign precisely the differences in kind of action between Narcotics and what are named Antispasmodics. The effects (hey produce are similar; they are capable of exciting the actions of the system, and they are often equally powerful in allaying pain and inordinate muscular action. But they do not in general produce that state of insensibility and diminished power which follows the application of narcotics, and this constitutes the difference between these classes. This might be supposed owing to a mere difference in strength;yet there seems also to be something farther than this, since antispasmodics produce no such effect in any dose, and since, although they are so much inferior to narcotics in these effects, they are equally powerful in repressing inordinate and irregular muscular action. This difference has been explained on the supposition, that as stimulants thej have less diffusibility and greater durability of action ; or else, that with their stimulant operation, they have no direct power of diminishing the powers of the system. Considered under either view, they form an intermediate class between Narcotics, which are so highly diffusible, and Tonics, which are much more permanent in their stimulant operation; and experience shows, that they partake of the properties of both; several narcotics and tonics being frequently used as antispasmodics, and the powers of those which more particularly constitute the class, in obviating spasmodic affections, being apparently connected principally with their stimulant power. From the name given to this class, their medicinal applications may be understood. Spasm is an irregular contraction of a muscle ; sometimes the contraction is permanent; at other times it alternates with relaxation, ANTISPASMODICS. 151 but even then are performed with more velocity, and the contractions are more powerful and more permanent than natural. Many diseases depend on spasmodic action, and others accompanied with affections of this kind. The medicines which obviate and remove such a state are termed Antispasmodics. Spasm may originate from various causes. One ofthe most fiequent is a strong irritation, continually applied, such as dentition, worms, or the presence of any foreign suostance in wounds. In such cases, narcotics must prove useful, by diminishing the irritability and sensibility ofthe system. Sometimes spasms appear to arise from mere debility , and the obvious means of removing this is by the use of tonics. Both narcotics and tonics, therefore, are occasionally useful as antispasmodics ; such, for example, as opium and ether in the one class, and zinc, mercury and Peruvian bark in the other ; and these are accordingly in common practice regarded as antispasmodics. But there are farther several substances which cannot be with propriety referred toeither of these divisions, as musk, castor, assafcetida, galbanum, valerian, &c.jj they are in some measure intermediate; and it is to these that the name of Antispasmodic is more exclusively appropriated. Few general observations can be made on this class of medicines. As their effect is not very permanent, they require to be given during the paroxysm of the spasmodic disorder, or a short time before its approach. For the same reason, the dose requires to be frequently repeated. Those, however, which belong to the class of tonics, require an opposite mode of administration; their beneficial effects being obtained only from their continued use. Some of those more strictly antispasmodics, stimulate the general system, and render the pulse more frequent ; but in general they can scarcely be regarded as medicines of much power. 152 ANTISPASMODICS. Moechus. Castoreum. Oleum animale empyreumaticum. succinum, oleum and acidum succinl. Bitumen petroleum. Carbonas ammonia pyro-oleosus. Ferula assafoetida. Huron galbanum. Sagapenum. "Valeriana ofeicinalis. Crocus sativus. Melaleuca cajuputi. NARCOTICS USED AS ANTISPASMODICS. Ether. Camphor. Opium. TONICS USED AS ANTISPASMODICS. Cuprum. Zincum. Hydrargyrus. Cinchona. Moschus. Musk. Moschus moschiferus. Cl.Mammalia. Ord. Pecora. Asia. The animal which affords musk, is a native of the elevated regions of the East of Asia. The musk appears to be a peculiar secretion, which is deposited in a small sac, situated nigh the umbilicus of the male. It is brought from China, or from India, in small membranous bags, covered externally with coarse hair. The musk within is in grains, is slightly unctuous, of a black colour, hav ANTISPASMODICS. 153 ing a strong durable smell, and a bitter taste. It yields part of its active matter to water, by infusion; by distillation the water is impregnated with its flavour; alcohol dissolves it, the impurities excepted. Musk is an antispasmodic supposed to be of considerable power; it is administered occasionally in the greater number of spasmodic diseases, especially in hysteria and singultus, and also in diseases of debility. In typhus fever it is employed to relieve subsultus tendinum, and other symptoms of a spasmodic nature. In cholera, it is given with the view of checking vomiting. Combined with ammonia, it has been celebrated for its power of arresting the progress of gangrene. With regard to its efficacy in some of these affections, its virtues have been perhaps exaggerated, and from this, as well as from its high price, it is not very often employed. Its dose is from 6 to 20 grains, repeated, if necessary, every five or six hours. It is best given in the form of bolus. To children, it has been given under the form of enema, as a remedy in the convulsions arising sometimes from the irritation of dentition. Offic. Prep.— Mist. Mosch. Lond.— Tinct. Mosch, Dub. C astoreum. Castor. Castor Fiber. Mammalia. Glires. The beaver, an amphibious quadruped, is a native of the North of Europe, Asia, and America. Castor is a peculiar product collected in cells near the extremity of the rectum, in this animal. It is imported of superior quality from Russia, and an inferior kind from New England. The former is dry, slightly unctuous; of a reddish brown colour, intermixed with fibres, and covered with a tough membrane; it has a strong unpleasant smell, and a bitter acrid taste. The American castor is more shrivelled, and inferior in taste and smell. The active matter of castor is dissolved by alcohol, proof spirit, and partially by water; the tincture with alcohol is the least nauseous. Vol. I. 20 154 ANTISPASMODICS. Castor is used as an antispasmodic, in hysteria principally, in a dose from 10 to 20 grains, or from 1 to 2 drachms of the tincture. From the experiments of Dr. Alexander, it appears to be a remedy of no power, as given in a quantity larger than its usual dose, it produced no sensible effect on the system. Offic. Prep.—T. Castor. Ph. Ed. Lond. Dub. T. Castor. Comp. Ed. Oleum Animale Empyreumaticum. EmpyreumatiG Animal Oil. Ol. Cornu Cervi. The fresh bones or horns of animals, when exposed to heat in close vessels, afford an empyreumatic oil, derived from new combinations of the elements of the animal matter attached to the phosphate of lime, which is the base of bone. The oil is at first of a thick consistence, black colour, and extremely foetid smell, but by repeated distillations becomes thinner, nearly colourless and transparent, though it remains still fcetid. In this state it has been used as an antispasmodic, in a dose of 10 or 15 drops. It retains its place in the Dublin pharmacopoeia, under the name of Oleum Cornu Corvini Rediricatum, being obtained in the distillation of hartshorn or bones, for the preparation of carbonate of ammonia ; but it is entirely discarded from practice. Succinum. Oleum et A<;idum Succini. The bituminous substance, amber, though it has a place in the list of the Materia Medica of the different pharmacopoeias, is perfectly inert, and is introduced only as affording, by distillation, an empyreumatic oil y which has been applied to some medicinal uses. This oil is at first thick and of a dark brown colour; but by repeated distillations with water it becomes limpid, still retaining however a very foetid odour. It has been celebrated for its antispasmodic power, and has been employed in hysteria andamenorrhoea in a dose from 10 to 15 drops. It is now discarded ANTISPASMODICS. 155 from practice, or is used only occasionally as an external stimulating application in paralysis and chronic rheumatism. Along with this oil, a peculiar concrete acid is produced in the distillation, which is at first impure, but is purified by sublimation, or by solution and crystallization. It has a place in the Edinburgh and Dublin pharmacopoeias, but appears destitute of any medicinal power, and is never applied to any use. Bitumen Petroleum. Petroleum Barb adense. Mineral Tar. Various kinds of liquid bitumens exist as natural productions, of different degrees of thickness, of a colour more or less deep, and also more or less volatile. That which has been usually kept in the shops, and applied to any medicinal use, under the name of Barbadoes Tar, is thick, of a dark brown colour, having a smell that is foetid, and a warm bitter taste. It has an analogy to the preceding empyreumatic oils in its properties; it has been used as an antispasmodic and sudorific, and externally as a stimulating application in paralysis. Though it retains its place in the pharmacopoeias, it is scarcely ever used. Carbon as Ammonije Pyro-Oleosus. Empyreumatic Carbonate of Ammonia^ Sal Cornu Cervi. The bones of animals, when exposed to a sufficient degree of heat, afford a large quantity of carbonate of ammonia, formed by new combinations of the elements of the animal matter contained in the bone. There is a similar production of empyreumatic oil, and with this oil the ammoniacal carbonate is always impregnated, whence it derives a peculiar foetid odour. It has also been supposed to derive from it certain medicinal powers, and has been used in preference to the pure carbonate of ammonia as an antispasmodic. Having been first procured from the bones of the deer, it has retained the name of Sal Cornu Cervi, and it still retains its place in the Dublin pharmacopoeia; being 156 ANTISPASMODICS. procured dissolved in the water which distils over, and this being rectified by repeated distillations. When thus rectified, it differs in little from pure carbonate of ammonia; and even combined with the empyreumatic oil, it has probably no additional medicinal efficacy, while from its fcetor it is unpleasant. Pure ammonia, dissolved in alcohol, is used as a solvent of the active matter of castor, assafcetida, and other antispasmodics, on the supposition that it coincides with them in their action on the system. Ferula Assafoetida. Assafcetida. Penfand. Digyn, Umbellata. Gximmi- Hesina. Persia. Assafoetida is a concrete gum-resin, obtained by exudation from incisions in the roots of the plant; the juice, after it exudes, being hardened by exposure to the sun. It is in small masses, adhering to each other, of a variegated texture, yellow on the external surface, white within, having an extremely foetid smell, and a taste bitter and subacrid. It consists of about two thirds of gum, and one third of resin, its taste and smell residing in the resinous part. It yields all its virtues to alcohol. Triturated with water, it forms a milky-like mixture, the resin being diffused by the medium of the gum. Distilled with water, it affords a small quantity of essential oil, extremely fcetid. Assafcetida is used as an antispasmodic in different nervous diseases, especially in hysteria, dyspnoea, dyspepsia attended with flatulence, and tympanitis, and is superior in efficacy to any of the foetid gums. Its usual dose is from 5 to 20 grains, in the form of pill, or diffused in water. It is likewise given under the form of enema, in tympanitis, flatulent colic, in the violent hysteric paroxysm, and as a remedy against worms, 2 drachms being diffused in 8 ounces of warm milk or water; it is sometimes applied externally as a plaster.* * The watery solution of assafcetida is one of the best remedies in pertussis. Its use however, should always be preceded by emetics, or by pretty active purging with calomel.—En. ANTISPASMODICS. 157 Offic. Prep. —Alcohol Ammon. Foetid. Emp. Asafoet. Pil. Assafoet. Comp. Tinct, Assafoet. Ed. —Mist. Assafoet. Lond. Dub. Enem. Foetid. Dub. Bdbon Galbantjm. Galbanum. Penland. Digyn. Umbellate. Gummi-Besina. Africa. Galbanum is obtained in the form of a milky juice, by exudation from incisions in the stem of the plant; when hardened it is in the form of a mass somewhat variegated in its texture, tenacious, of a yellowish brown colour, having a foetid smell, and a bitter acrid taste. Alcohol dissolves its resin, in which its powers have been supposed to reside; proof spirit dissolves it entirely, the impurities excepted. Triturated with water, it is diffused, and forms a milky-like fluid; by distillation it affords about one twentieth of its weight of essential oil. Galbanum has the virtues of the foetid gums, and is used for the same purposes ; but being inferior in strength to assafcetida, it is less employed. Its dose is fen grains. Externally, it is more frequently used as a discutient to indolent tumors, and as a stimulant to promote suppuration. Offic. Prcp.—V\\. Galb. Comp. Lond.— Tinct. Galban. Dub. —Emp. Galb. Comp. Lond. Dub. Sagapenum. Gummi-Resina. This gum-resin, usually imported from Alexandria, is the produce of an unknown tree said to be a native of Persia. It is in small masses, of a yellow colour, having a smell slightly foetid, and a pungent nauseous taste ; it is soluble in proof-spirit; by distillation it affords a small quantity of essential oil. Its virtues and uses are the same as those of assafcetida, to which, however, it is much inferior in power, and is therefore seldom employed. Its dose is from ten to twenty grains. It is sometimes applied externally as a discutient. 158 ANTISPASMODICS. Valeriana. Officinalis. Wild Valerian. Triand. Monogyn. Aggregates. Radix. Indigenous. The root of this plant, which is the part used in medicine, consists of a number of slender fibres twisted, and attached to one head, of a light brown colour, having a smell strong and unpleasant, and a warm bitter taste. Its active matter is dissolved equally by water and alcohol, and appears therefore to consist of extractive matter, with perhaps a small portion of tannin, as its infusion changes colour on the addition of sulphate of iron. By distillation, water is impregnated with its flavour, but not with its taste, and no sensible quantity of essential oil is obtained. Valerian is one of the principal modern antispasmodics, and is employed in hysteria, chorea, and epilepsy, where these depend not on organic derangement, or on any permanent irritation, but on increased susceptibility of the nervous system. Sometimes also, it is used with advantage in hemicrania. Its dose is from one scruple to one drachm, three or four times a-day, which is increased gradually as far as the stomach can bear it. Sometimes it is taken under the form of infusion. Offic. Prep. —Tinct. Valer. Tinct, Valer. Amnion. Ph. Lond. et Dub. —Extr. Valer. Infus. Valer. Dub. Crocus Sativus. Saffron. Triand. Monogyn. Liliace CoNVOLVOEtJS JAEAPA. HeLEEBORCS NIGER. Bryonia alba. Cucumis coeocynthis. momordica eeaterium. Rhamnus CATHARTICUS. Aloe ferfoliata. convolvolus scammonia, Stalagmitis CAMBOGIOIDKS Scb-MUUIAS HYDRARG YRI. Sulphas magnesia. Sulphas sodje. Sulphas Potass*, super-tartras potass.e. tartras potass*, tartras potass* et sod*. Phosphas SODJE. MlTKIAS SOS*. Terebinthina veneta. Nicotian a Tabacum. 265 CATHARTICS. LAXATIVES. Manna. Manna. Fraxinus Ornus. Fraxinus Rotundifolia. Polygam, Diccc. Ascyroid. Succus concretus. South of Europe. This substance, though afforded by several vegetables, is usually obtained from different species of the ash-tree, particularly those mentioned above, which are cultivated in Sicily and Calabria. It is procured by spontaneous exudation, but more copiously by incisions made in the bark of the trunk. The juice, which exudes, soon becomes concrete. When it exudes slowly, the manna is more dry and white, and of a texture somewhat granulated, forming what is named Flake Manna. When the exudation is more copious, the juice is of a darker colour, and concretes into a soft unctuous-like mass, less pure than the other. Manna has a sweet, though somewhat unpleasant taste, and possesses the general chemical properties of saccharine matter; it is entirely soluble in water and alcohol. The chemical difference between it and pure sugar is not very well established. When dissolved in alcohol, with the aid of heat, the solution on cooling deposites crystals apparently purely saccharine ; and by concentration of the residual liquor, a mucilaginous extractive matter remains not crystallizable, having the peculiar taste of the manna. Although sugar in its unrefined state proves laxative, manna is so in a greater degree. The dose of manna, as a laxative, is from one to two ounces to an adult, but it scarcely operates with sufficient effect to admit of being employed alone. Though mild in its operation, it is apt to produce flatulence and griping, and hence it is principally used in combination with other cathartics, particularly with senna, the bitter taste of which it covers. This combination is in common use as a purgative to children. Offic. Prep. —Syrup. Manne. Pharm. Dub. " Vol. I. 31 266 CATHARTICS. Cassia fistula. Purging Cassia, or Cassia in pods. Decand. Monog. Lomentacece. Fructus; Pulpa Fructus. Egypt; East and West Indies. The fruit of this Iree is in pods, nearly an inch in diameter, and ten or twelve in length. The external membranous part is firm and hard, the pulp within is of a black colour, and has a sweet taste, with a slight degree of acidity. It is extracted by boiling the bruised pods in water, and evaporating the decoction. It is soluble in water. According to Vauquelin's analysis of it, it contains, besides the fibrous part, gluten, jelly, mucilage, and saccharine matter. This pulp proves gently laxative in a dose of four or six drachms; in the large dose necessary to occasion purging, it is apt to induce nausea or griping, and even as a laxative it has no particular advantage. The sole consumption of it is in the composition of the officinal preparation known by the name of Electuarium Sennae. There is another electuary in the pharmacopoeias, to which, as being the principal ingredient, it gives its name, and in which it is combined with manna and pulp of tamarinds, but this is never used. Offic. Prep. —Elect. Cass. Fht.Ed. Lond. Bub. Tamabindus indica. Tamarind. Monadelph. Triand. Lomentacece. Fructus conditus. East and West Indies, America, Arabia. The pod of this tree includes several large hard seeds, with a brown viscid pulp, very acid. This pulp, mixed with the seeds and small fibres, and with a quantity of unrefined sugar added to preserve it, forms the Tamarinds of the shops. Vauquelin found it to contain, besides the sugar mixed with it, citric and malic acids, super-tartrate of potash, tartaric acid, jelly, mucilage, and fibrous matter. The pulp of tamarinds, besides its virtues as an acid, proves laxative, when taken to the extent of an ounce, or an ounce and a half, but it is too weak to be employed alone. It is generally added to other cathartics, which are 267 CATHARTICS. given in the form of infusion, with the view of promoting their operation or of covering their taste. It is an ingredient in the Electuarium Sennas, and there is an officinal infusion of it with senna, which affords a very pleasant purgative. Offic. Prep. —Inf. Tarn. Ind. cum Cass. Sen. Ed. There are some other sweet fruits which have a laxative quality as the Pig (Picus Carica,) and the Prune (Prunus Domestica.) These are sometimes used in domestic practice, and they are also ingredients in the Electuary of Senna. Ricinus communis. Palma Christi. Monxc. Monadelph. Tricoceee. Oleum, Semen. West Indies. The seeds of the capsules of this plant are farinaceous, with a considerable quantity of unctuous matter intermixed. They afford, by expression or decoction, an oil which is used in medicine in this country under the name of Castor Oil. When obtained by decoction of the bruised seeds in water, it is purer and less acrimonious than when obtained by expression. It is of a yellowish colour, and has scarcely any peculiar taste or smell. It is the only example of an expressed oil having any medical activity. As a laxative, castor oil acts mildly, and at the same time very effectually ; it also operates in a shorter time than almost any other cathartic. Possessed of these advantages, it is a cathartic frequently employed ; and is more peculiarly adapted for exhibition, where any degree of irritation is to be avoided. Its dose is one ounce. It is taken floating on pepper-mint water, mixed with any spiritous liquor, or any purgative tincture, as that of senna ; or diffused in water by the medium of gum. sugar, or the yolk of an egg. 268 CATHARTICS. From the Mineral Kingdom, two laxatives, are derived, Sulphur and Magnesia. Sulphur is an inflammable substance, found in nature, nearly pure, and likewise in combinat ion with several of the metals. The greater part of the sulphur of commerce is the produce of volcanic countries. It is naturally mixed with earthy matter, from which it is freed by sublimation, forming the Sulphur Sublimatum, Flores Sulphuris, or Flow ers of Sulphur. When melted and run into cylindrical molds, it forms Roll Sulphur, which is usually less pure. Sulphur is of a light yellow colour; is insipid ; has a faint smell, when rubbed or heated ; is very fusible and volatile; and when heated in atmospheric air, burns with a blue flame, and the production of suffocating fumes. It is insoluble in water or alcohol, but is dissolved by oils, and combines with the alkalis, several of the earths, metals, and metallic oxides. It was, until lately, regarded as a simple substance ; there is reason to believe, however, that it contains hydrogen, and that the pure inflammable base has not yet been obtained. Sulphur in a dose of 2 or 3 drachms, acts as a laxative, and so mildly, that it is often used in hemorrhoidal affections, and in other cases where, though the operation of a purgative is indicated, any irritation w ould be injurious. It likewise passes off by the skin, and is administered internally, and is applied externally in psora. In habitual dyspnoea and in chronic catarrh, advantage has been derived from it, probably partly from its action as a laxative, and partly as a diaphoretic. The solution of it in oil has been used in these cases, but this preparation is both acrid and extremely nauseous. Sulphur is always best given in the form of electuary. The purification of sulphur by washing is ordered in the pharmacopoeias, but is a process altogether unnecessary. Precipitated by an acid from its solution by an alkali or lime, it is obtained of a whiter colour than in its usual state, and this precipitated sulphur is used in preference 269 CATHARTICS. to the sublimed sulphur in forming ointments. The combination of it with potash, Sulphurettum Potassa?, has also been introduced into the pharmacopoeias, principally with a view of affording a substance which has been supposed capable, by its chemical action, of counteracting the operation of metallic preparations where these have been taken in excess. Offic. Prep. —Sulphur Lotum. 01. Sulph. Ung. Sulph. Ph. Ed. Lond. Dub.— Sulph. Precipit, Ph. Lond. —Sulph. Potass. Ed. Dub. Magnesia is a simple earth, not found pure in nature, but existing abundantly combined with certain acids, and from these saline combinations it is obtained by processes to be afterwards noticed. Either pure or in the state of carbonate, it is used as an antacid and laxative, in a dose of a drachm or more. Its laxative effect is generally considered as owing to its forming with the acid in the stomach a saline combination, which, like its other salts, is purgative, though, as it generally has this effect, it probably has itself a weak cathartic quality. From being insipid and mild, it is well adapted for exhibition to infants. PURGATIVES. Cassia Senna. Senna. Decand. Monog. Lomonlacca. Folia. Egypt. Arabia. The dried leaves of this plant are of a yellowish green colour; have a faint smell, and a bitter taste. Their active matter is extracted both by water and alcohol by infusion. By decoction with water, its activity is much impaired. Senna is a purgative very frequently employed, having a considerable degree of activity, without being liable to be violent in its operation. It is usually given in the form of the w r atery infusion, 2 drachms being in- 270 CATHARTICS. fused in 4 or 6 ounces of tepid water, generally with the addition of a few coriander seeds, to cover its flavour, and obviate griping. It is also frequently combined with manna, with tamarinds, or with super-tartrate of potash; and as its taste can be covered by sugar or manna, it is a purgative very generally given to children. There is an officinal tincture of it which operates as a purgative in the dose of an ounce; there are also officinal infusions of it; and it enters into the composition of several other preparations employed as cathartics. Qffic. Prep. —Elect. Cass. Senn. Extr. Cass. Senn. Inf. Tarn. Ind. cum Cass. Sen. T. Cass. Senn. C. Ed. —Inf. Senn. Pulv. Senn. C. Lond. —Syrup. Senn. Lond. Dub. Rheum pa.ema.tcm. Rhubarb. Enneand. Trygyn. Oleracea. Radix. Tariary. Besides the Rheum Palmatum, two other species, the Rheum Undulatum, and Rheum Compactum, are cultivated with the view of obtaining their roots, to be used in medicine; nor is any considerable difference, it is said, to be observed, between the root obtained from any of them when it is properly dried and preserved. The best Rhubarb is that named Russian or Turkey ; it is in small pieces, with a large hole in the middle ; of a lively yellow colour, with streaks of white; has a smell peculiar, and somewhat aromatic ; and a bitter slightly styptic taste. Another kind is imported from the East Indies, or rather from China, in larger masses, more compact and hard, heavier, less friable than the other, and having less of an aromatic flavour. Rhubarb, cultivated in this country, has been prepared equal to either of the others, but in general it is inferior, probably from less care being bestowed on its cultivation and preparation. The active principles of rhubarb are not very well ascertained. It is somewhat mucilaginous, and yields part of its powers to water by infusion. Alcohol likewise dissolves a considerable proportion of it; and diluted alcohol appears to be its most proper solvent, CATHARTICS. 271 dissolving all its active matter. It appears too to contain a portion of tannin, as it gives a deep colour with the salts of iron. It has the combination, rather singular, of an astringent with a cathartic power ; and it does not appear from any analysis of it, whether these reside in different proximate principles or not. The watery infusion is said to be more purgative than the spiritous, and by applying heat to the rhubarb in substance, its purgative quality is lessened, while its astringency remains. The Chinese rhubarb is supposed to be more astringent than the Turkey. Every kind of it contains a quantity of earthy matter, chiefly lime, combined with sulphuric and citric acids, forming the principal part of the white streaks. This is generally more abundant in the Turkey rhubarb than in the others. The dose of rhubarb as a cathartic is one scruple or half a drachm. Along with its purgative operation, itexerts a moderately astringent power, and has hence been considered as peculiarly adapted for exhibition in diarrhoea, any acrid matter being evacuated before it acts as an astringent. From the conjunction of bitterness with these qualities, it is likewise often used in dyspepsia and hypochondriasis, to obviate costiveness. And it enters into a number of officinal preparations, in which it is either the principal medicine, or combined with aloes, bitters, or aromatics. Offic. Prep.—Inf. Rhei P. T. Rhei P. Eel Lond. Dub.—V'm. Rhei. T. Rhei et Aloe. Tinct. Rhei et Gent. Pil. Rhei. C. Ed.— Tinct. Rhei, C. Extr. Rhei. Lond. Convoxvolus j at. apa. Jalap. Pentand, Monogyn. Campanace*. Radfa. Mexico. The dried root of jalap is imported in thin tansverse slices ; it is solid, hard, and heavy ; of a dark gray colour, and striated texture. It has little smell; its taste is bitter and subacrid. Jalap contains a resinous and a gummy matter, its purgative quality appearing to reside in the former, as if is extracted by alcohol, whileits watery infusion is comparatively inert. Proof-spirit is its proper menstruum. 272 CATHARTICS. This root is an active purgative, producing full evacuation from the intestines; sometimes occasioning, however, nausea or griping. Its medium dose is half a drachm. Besides being given alone, it is very frequently used to quicken the action of other cathartics, of mild muriate of mercury for example; or it is combined with others, which are supposed to render it less stimulating, as with the super-tartrate of potash. It operates most mildly and effectually in substance, and is therefore seldom given under any'form of preparation. Offic. Prep. —T. Conv. Jal. Ed. Lond. Bub.—Exir. Conv. Jalap. Ed. Bub. —Pulv. Jalap, C. Ed. Heleeborus nicer. Melampodium. Black Hellebore. Polyand. Polygyn. Multisiliqute. Radix. Austria. Italy. The root of this plant consists of short articulated fibres attached to one head, externally dark coloured, internally white. Its taste is very acrid, but the acrimony is much impaired by drying and by age. Its active power seems principally to reside in its resinous part. By decoction with water it yields half its weight of gummy matter, with some resin; and the extract obtained by inspissation of this, is milder than the root itself. Its distilled water, it is affirmed, is acrid, and even cathartic. Black hellebore root is a very powerful cathartic, so violent, indeed, and at the same time uncertain in its operation, that it is scarcely ever used in substance : the watery extract of it, which is milder, has sometimes been employed. On its cathartic power probably depends any advantage that may be derived from its administration in mania and melancholia, in which diseases it was highly celebrated by the ancients. In dropsy it has been employed as a hydragogue cathartic, principally under the form of the spiritous extract. It was likewise strongly recommended by Mead as an emmenagogue, in the form of tincture, but with others has sel dom been successful. Offic. Prep.—T. Helleb. N. Ed. Lond. Bub.—ExU, Helleb. Ed. Bub. CATHARTICS. 273 Bryonia, av.ua. Bryony. Mon with little smell. They prove emetic and cathartic, bui 302 DIURETICS. in a smallerdose produce a diuretic effect, and have been recommended under the form of infusion in the treatment of dropsy. Their operation, however, is always uncertain and liable to be violent. Spabtipm scopabium. Broom. Diadelph. Deeand. Papilionacc XXV. Ointments, 286 XXVI. Plasters and Cataplasms, ..... 302 CONTENTS. IV APPENDIX. Of Mineral Waters, - - - 312 the Gases as remedies, ... 330 Electricity, ... - 339 Galvanism, - 341 Medical Prescriptions, and of the Doses of Medicines, - - - - 343 Tables of Changed Names, .... 349 English Index, ------ 365 Latin Index, - - - - 373 PART II. OF PHARMACY. THE objects of Pharmacy are the Preservation,Preparation, and Composition of Medicines. In the state in which these are afforded by nature, they are not always best adapted to the treatment of disease: they are often liable to change from spontaneous decompositions, which require therefore to be counteracted: their powers sometime reside, not in the entire matter of which they consist, but in principles capable of being extracted, and which are employed with advantage in an insulated state, or under peculiar forms; by chemical combinations, remedies altogether new are obtained; and, lastly, medicines frequently require to be combined to fulfil particular indications, or they are rendered more pleasant, more safe, and even more active, when given in a state of mixture. Pharmacy, regarded as an art, prescribes the rules by which the operations for the attainment of these objects are conducted, and as a science unfolds the principles on which they depend. The Preservation of Medicines is generally speaking the least important part of Pharmacy. Those which are most liable to decomposition are the vegetable products, many of which, especially w hen the re-action of their elements is favoured by humidity, suffer such changes as weaken their medicinal properties. Changes, productive of the same result, are not unfrequently ocea- Vol. II. 2 PHARMACY. 2 sioned by the action of air and light. The methods by which these are counteracted, of which the most important is Exsiccation, belong to this division of Pharmacy. Jt includes too the few general rules which are observed in collecting plants in that state of vigour and maturity in which they are possessed of the greatest degree of activity. And there belong to it also those operations which are necessary to preserve unaltered the few animal products employed in medicine. Under the second branch of Pharmacy, the Preparation of Medicines, are included a number of important operations, agreeing in general in affording substances different, more or less in chemical constitution, from the s u bstances operated on. The medicinal powers of vegetable substances, it has already been remarked, frequently reside in peculiar proximate principles, which, from their relations to certain solvents, can be separated from each other; and thus, in many cases, the principle on which the medicinal activity of the substance depends, can be obtained in a pure and concentrated state. Resins, for example, are dissolved by alcohol, gums by water, extractive matter by either of these liquids, or by a mixture of both; and by this separation advantages are often obtained ; the medicine is rendered more certain in its operation; it is more easily preserved, or more conveniently administered. On this are founded the various pharmaceutic preparations of infusions, decoctions, tinctures, medicated wines or vinegars, and extracts; —forms under which medicines are often employed in preference to their natural state. The proximate principles of plants are sometimes obtained apart by other processes, as by distillation, or even by mechanical expression, whence other forms of preparation are obtained. To this division belong too the Saline and Metallic Preparations. These are entirely the results of chemical processes; they are new remedies formed by chemical combination, and are possessed of properties altogether PHARMACY. 3 different from those of the substances from which they are prepared. In all these preparations, chemical changes are produced to a greater or less extent. Medicines are also, however, frequently given in a state of mixture, in which they either exert no mutual chemical action, or none producing any modification of their powers. This forms what is named Composition in Pharmacy. It is employed with different views; sometimes, for example, to conceal a medicine, to render it less unpleasant, or to give it a convenient form. And frequently more important advantages are attained; the action of one medicine on the system, or on a particular organ, so far co-operating with that of another, as to render its operation more certain, or more powerful, or even sometimes giving rise to such a modification, as to produce an effect different from that which would be obtained from the action of either. Pharmacy, as practised in this country, is regulated by the Pharmacopoeias of the respective Colleges. As many of the processes, however, are necessarily alike, there is no advantage in inserting the formula for every preparation, according to the different Parmacopoeias. I have, therefore, followed a different method. Taking the Edinburgh Pharmacopoeia as the basis of this part of the work, and adopting its arrangement and nomenclature, I have added, to a translation of its processes, such observations as appeared to me necessary under each, on the theory of the operation, the circumstances to be attended to in conducting it, and the medicinal powers and applications of the substance formed. The corresponding preparations in the London and Dublin Pharmacopoeias I have thought it sufficient to indicate merely by name, where the processes by which they are obtained- do not differ essentially from those of the other. When they do differ in any important particular, I have introduced them into the text, and I have also SIMPLE PREPARATIONS. 4 given a place to the few preparations which have none corresponding to them in the Edinburgh Pharmacopoeia. A system of Pharmacy is thus presented, without that tedious repetition, which is unavoidable, when the processes of all the Pharmacopoeias are regularly introduced. CHAPTER I. PREPARATIONS OF SOME SIMPLE MEDICINES. The first chapter in the Edinburgh Pharmacopoeia is a miscellaneous one, including under this title, a few preparations which could not well be placed under the other chapters. 1 have added to it some similar preparations from the London and Dublin Pharmacopoeias. Herbarum et florum exsiccasio. Drying of Herbs and Flowers. " Herbs and flowers are to be dried with the gentle heat of a stove, or a common fire, in such a quantity that the drying may be performed as quickly as possible. Their virtues are thus best preserved, the mark of which is their retaining completely their native colour. The leaves of hemlock, and others containing a subtile volatile matter, are, immediately after drying, to be rubbed to powder, and kept in glass vessels well stopt." Directions nearly similar are given by the Dublin College. By drying herbs and flowers, or expelling a great part of the water they contain, those spontaneous chemical changes which are favoured by humidity are prevented, and they are rendered capable of being preserved. The more quickly they are dried, they retain in general their virtues more completely, care only being taken that too much heat be not applied, as part SIMPLE PREPARATIONS. 5 of their volatile principles would be dissipated, and their flavour and medicinal qualities impaired. Even when dried, they surfer some changes in keeping, probably from the action of the air and light; and some do so more rapidly than others. Hemlock, in particular, has its colour and odour impaired in a very short time ; it is therefore necessary to exclude it from the air, and likewise from exposure to light. Scilla maritima exsiccata. Dried Sea Squill. " Cut the root of the sea squill, its outer covering having been removed, transversely, into thin slices, and dry it by a gentle heat. The mark of its being properly dried is, that while it is rendered friable, it retains its bitterness and acrimony." By drying, the squill loses about four-fifths of its weight, and with very little diminution of its powers, if too much heat has not been applied. It is in this state that squill is commonly employed in medicine, and for other pharmaceutic preparations. It requires to be kept in a dry place, as otherwise it regains its softness, and is liable to become mouldy. Pulparum extractio. Extraction of Pulps Those fruits which afford a pulp, if they are unripe, or if ripe and dry, boil with a little water, that they may become soft. Then express the pulp through a hair-sieve, and boil it with a gentle heat in an earthen vessel, stirring it frequently that it may not burn, until it attain the consistence of honey. The pulp of cassia fistula is to be boiled from the bruised pod; and then by evaporating the water, to be reduced to the due consistence. The pulps of ripe and fresh fruits are to be pressed through a sieve, without previous boiling. These directions are given principally for the preparation of the pulps of several fruits which enter into the composition of the Electuary of Senna. Pulps are sel- SIMPLE PREPARATIONS. 6 dom otherwise medicinally employed, and they cannot be long preserved unchanged. The following general directions are given in the London Pharmacopoeia, for collecting the vegetable articles of the Materia Medica. " Vegetables are to be gathered from the soil and situations where they spontaneously grow, at a dry season, and not moistened with rain or dew; they ought to be collected annually, and if they have been kept for a longer period, ought to be rejected." " Roots, in general, are to be dug up before their stalks or leaves shoot forth." " Barks ought to be collected at that season at which they are most easily separated from the wood." " Leaves are to be gathered after the flowers have unfolded, and before the seeds have ripened." " Flowers are to be collected recently blown." " Seeds are to be taken when they are ripe, and before they begin to fall from the plant. They ought to be preserved in the seed vessels." PREPARATION OF VEGETABLES. Pharm. Lond. " Vegetables, soon after they are collected, those excepted which are to be used in the recent state, are to be spread out lightly, so as to dry as quickly as possible, with a heat so gentle, that their colour may not change; they are then to be kept in proper vessels, or situations where the access of light and humidity may be excluded." Roots, which are ordered to be kept fresh, ought to be buried in dry sand. The root of squill before drying it, is to be cut transversely into thin slices, the outer dry layers being removed." " Pulpy fruits, if they are not ripe, or, if ripe and dry, are to be exposed in a damp place until they become soft, then press out the pulp through a hair-sieve, SIMPLE PREPARATIONS. 7 afterwards boil with a gentle heat, stirring frequently ; lastly, dissipate the water by the heat of a water bath, until it has become of the proper consistence." " On the pods of cassia bruised, pour boiling water, so as to wash out the pulp, which press first through a sieve with large holes, afterwards through a hair sieve, then evaporate the water by the heat of a water-bath, until the pulp attain the proper consistence." " Press the pulp or juice of ripe and fresh fruits through a sieve without any previous boiling." OF GUM-RESINS. Pharm. Lond. " Separate Opium carefully from extraneous substances, especially on its external surface. Let it be kept in the state of soft Opium, fit for forming pills; and hard Opium, rendered so by having been dried in the heat of a water-bath, so that it can be rubbed to powder." " Those Gum-Resins are to be accounted of the best quality, which can be selected so pure, as to require no purification. If they appear to be less pure than this, boil them in water until they become soft, and press them by a press through an hempen bag ; then put them aside, that the resinous part may subside. The liquor above being poured off evaporate it by the heat of a waterbath, adding towards the end of the evaporation the resinous part, and mixing it thoroughly with the gummy part into one mass." " Those Gum-Resins which melt easily may be purified by being put into an ox bladder, and kept in boiling water until they become soft, so that they may be separated from the impurities by being pressed through an hempen cloth." 44 The Balsam of Storax is to be dissolved in rectified , spirit, and strained ; the spirit is then to be distilled with a gentle heat, until the balsam become of the proper consistence." These directions, for the purification of Gum-Resins, are the most proper perhaps that can be given; but they 8 SIMPLE PREPARATIONS. are omitted by the Edinburgh College, as it is always preferable to use them medicinally, only when in that state in which they do not require purification ; for, however cautiously the operation may be performed, they are always liable to surfer some change, either from the dissipation of volatile principles, or from changes of composition in those which are fixed. The process is admissible, therefore, only with regard to gum-resins, which are to be applied externally, as ammoniac or galbanum, when they are to form the basis of plasters. Storax is a substance so rarely empioyed in medicine, that the ordering it to be puritied may be regarded as superfluous. The Dublin College have ordered its purification, by digesting it in water with a gentle heat, and pressing it when soft between plates of iron, made hot in boiling water, —a process which must dissipate its odorous matter, on which all its powers depend. The directions given by the London College with regard to Opium, are preferable to a process formerly admitted, and which is to be afterwards noticed, as being retained in the Dublin Pharmacopoeia, in which opium is dissolved in proof spirit, and the tincture strained, and again evaporated to the due consistence, —a process in which the opium always sustains a diminution of power. PREPARATIONS FROM ANIMALS. Pharm. Lond. Adefs Prepared Lard. " Cut the fat into small pieces; then press it, liquefied by a gentle heat, through linen." Sevum prjeparatum. Prepared Suet. " Cut suet into pieces; then press it, melted by a gentle heat, through linen." The design of these processes is to free the fat from the membranous fibres intermixed with it; but, as it is generally prepared before it is brought to the shops, the Edinburgh College have omitted the directions they SIMPLE PREPARATIONS. 9 formerly gave. If the heat be raised too high, the fat acquires a brown colour and empyreumatic smell ; it is therefore usually melted with a little water, by which this is prevented. Cornu ustum. Burnt Horn. Ph. London. (Pulv. Cornu. Cerv. Uust. Ph. Dub.) " Burn pieces of horn in an open fire, until they become perfectly white ; then rub them to powder, and prepare them in the same manner that chalk is prepared." The base of horn, like that of bone, consists of phosphate of lime, or at least it is this eanhy compound that remains when bones are burnt, mixed with a little carbonate and sulphate of lime ; and in the bones of some animals, phosphate of magnesia and rluate of lime. The gelatin of the horn or bone is decomposed during the burning ; its carbonaceous matter partly remains, giving a black colour, but by continuing the heat, this also is burnt out. The phosphate of lime is a substance apparently altogether inert, though, from a theoretical view, as to the cause of rickets and mollities ossium, it has been proposed to be given as a remedy in these diseases. It is used to reduce substances which are rather soft and tenacious, as opium, to powder, being rubbed along with them ; and its powder is sometimes employed as a dentifrice. Spongia usta. Burnt Sponge. Ph. Lond. (Pulvis Spongise Ustae, Ph. Dub.) " Cut sponge into pieces ; and bruise it, so that it may be freed from adhering extraneous bodies ; then burn it in a close iron vessel, until it become black and friable ; lastly, rub it into a very fine powder." Burnt sponge has been celebrated as a remedy in bronchoceie, and in scrofulous affections of the glands, given in a dose from 20 to 30 grains. It consists chiefly of carbonate of soda and carbonaceous matter ; but it has been stated as a reason for its being retained in the Vol. II. S SIMPLE PREPARATIONS. 10 London Pharmacopoeia, that it produces effects as a medicine, which are not to be obtained from a mixture of the alkali and charcoal alone. Burnt sponge has likewise a place in the Dublin Pharmacopoeia, being prepared in a similar manner; and the following preparation is likewise inserted, which probably affords an analogous product. Pulv. quercus marine. Powder of Sea Oak, or Sea Wrack* Pharm. Dub. " Take of sea wrack with its vesicles any quantity. Free it from its impurities and dry it ; then put it into an iron pot or crucible with a perforated cover, and expose it to the fire, until the vapour which arises cease, and the mass become of a dull red. Reduce the carbonaceous residuum to powder, and preserve it in close vessels." Testae Prepared Shells. Pharm. Lond. " Wash the shells previously freed from impurities with boiling water ; then prepare them in the manner ordered with regard to chalk." This process is designed to give a carbonate of lime purer than the prepared chalk. The product is at least more Smooth, and free from the coarser earthy matter diffused through chalk. It contains too a portion of animal matter, probably gelatin, but so highly indurated as not to be easily extracted by water, and not to be liable to spontaneous decomposition. Under this chapter, the Edinburgh College have inserted a preparation of sulphur, the Washed Sulphur; to which may be addeVl, the Precipitated Sulphur of the London Pharmacopoeia. SIMPLE PREPARATIONS. 11 Sulphur Sublimatum lotum. Washed Sublimed Sulphur. " Take of Sublimed Sulphur, one pound; water, four pounds. Boil the sulphur for a short time in the water, then pour of! this water, and adding cold water wash away all the acid ; lastly, dry the sulphur." A similar process has a place in the Dublin and London Pharmacopoeias. The sublimation of sulphur is usually conducted on a large scale, and the vapours of the sulphur, which first rise, receiving a little oxygen from the atmospheric air of the subliming vessel, or of the chamber in which they are condensed, a slight degree of acidity is liable to be acquired, which it is the object of this process to remove. Any acidity, however, is so slight, that it is scarcely perceptible in the sublimed sulphur of the shops; the process is therefore surperiluous, and is never attended to. Sulphur Precipitated Sulphur. Pharm Lond. " Take of Sublimed Sulphur, one pound; lime recently prepared, three pounds. Boil the sulphur and the lime together in water; strain the liquor through paper, and drop into it muriatic acid, as much as may be sufficient, to precipitate the sulphur. Lastly, pouring water on this frequently, wash it until it remain tasteless." The sulphur is in the first stage of this process combined with the lime; and, at the same time, as always happens when stdphur is enabled to act on water, by the resulting affinity of an alkaline base, a decomposition of a portion of water takes place; its oxygen unites with a little of the sulphur, and forms sulphuric acid, with which part of the base combines; the hydrogen of the decomposed water unites with another portion of sulphur, forming sulphuretted hydrogen, and this enters into combination with the remaining sulphur, and base, and by its affinity prevents any farther decomposition. The solution, therefore, neglecting the small portion of sulphate which it may contain, is a ternary SIMPLE PREPARATIONS. 12 compound of sulphur, sulphuretted hydrogen, and the alkaline or earthy base. When an acid is added, it combines with the base, and precipitates the sulphur, while the small quantity of sulphuretted hydrogen is disengaged in the elastic form. In the present process, therefore, the solution obtained by boiling the lime and sulphur, is a compound of these with sulphuretted hydrogen, what may be named a Sulphuretted Hydrosulphuret of Lime. On adding muriatic acid, it combines with the lime; and this muriate of lime being very soluble, remains dissolved in the water; the sulphuretted hydrogen is disengaged; and the sulphur being insoluble is precipitated. The process, under this point of view, may be supposed to have no object, as the sulphur is merely recovered; and it cannot indeed be said to have much advantage. The precipitated sulphur, however, is of a whiter colour than sublimed sulphur, and is therefore preferred in making sulphur ointment, the only purpose to which it is applied. This whiteness may be owing either to its state of aggregation, or to its combination with a little water, for the yellow colour is restored on melting it. That it is owing to the presence of water, is rendered probable, from the same whiteness being produced by dropping water on melted sulphur, or receiving the vapours of sulphur in a vessel filled with watry vapour. Common sulphur, it appears from recent experiments, contains hydrogen with a little oxygen; and it is not improbable, that precipitated sulphur may contain a larger proportion of hydrogen, which it may attract in its precipitation. The whiteness of the precipitated sulphur of the shops is usually increased by precipitating the solution of the sulphuretted hydrosulphuret of lime, not by muriatic, but by sulphuric acid, the sulphate of lime being thrown down, intimately mingled with the sulphur. This renders it less fit for internal administration. CONSERVES. 13 CHAPTER II. CONSERVE.—CONSERVES. Conserves are compositions of fresh vegetable matter with sugar. The form is designed to preserve such vegetables as lose their virtues by drying : to obviate the decomposition to which this matter is liable, three times its weight of refined sugar is in general necessary. The active matter of vegetables is, however, generally injured by keeping in this form ; and, therefore, there is no conserve ordered in the Pharmacopoeia of any powerful medicine, those which are inserted being merely recommended by their agreeable flavour, and being not used but as vehicles for the exhibition of more active remedies, under the form of bolus, pill, or electuary. In the Edinburgh Pharmacopoeia there are the following conserves: Conserva extenoris recentis fructus Citri Aurantii radula abrasa. Conserve of the outer rind of the Orange rasped by a grater. Conserva Fructus Caninje maturi, a seminibus eorumque pube sollicite purgati. Conserve of the fruit of the Dog-hip, carefully freed from the seeds and included down. Conserva Petalorum Ros/E Gallics nondum explicitorum. Conserve of the unblown Petals of the Red Rose. In the preparation of these, the vegetable matter is directed to be beat into a pulp, to which is to be added gradually, during the beating, three times its weight of refined sugar. The first of them, the Conserve of Orange Peel, is so little used, that it is seldom to be found in the shops. The Conserve of Dog-hip is smooth and uniform in its consistence, and is therefore well adapted to the purpose JUICES. 14 to which it is applied, that of serving as a vehicle for active medicines, under the form of bolus or pill. The Conserve of the Petals of the Red Rose is supposed to retain their slight astringency, and at one time was celebrated as a remedy in haemoptysis and phthisis. It is still a popular medicine in these diseases, being taken in the dose of an ounce in the morning, diffused in warm milk. The London College have united the Conserves with the preparations named Electuaries, and have given them the common name of Confections. Of those which correspond with what have usually been denominated Conserves, they have retained the three which have a place in the Edinburgh Pharmacopoeia. The Dublin College admit only the Conserve of the Rind of the Orange, and the Conserve of the Petals of the Red Rose. CHAPTER III. SUCCI.—JUICES. Juices are obtained from fresh vegetables by expression. They consist chiefly of the sap of the plant, mixed, however, more or less, with the proper juices; and according as these are in greater or less abundance, or easily expressed from their vessels, the juice will be more largely impregnated with them. It may hold dissolved mucilage, extractive matter, tannin, and any of the vegetable acids; and fecula is frequently suspended in it, with sometimes perhaps a portion of resin, diffused by the medium of the other principles. When newly expressed, these juices are generally impure and viscid: on standing for some time, they deposite a quantity of mucilaginous matter, along with grosser impurities; the clear liquor is poured off, and passed repeatedly through a fine linen cloth, by which it is rendered more pure. A small quantity of alcohol, INSPISSATED JUICES. 15 generally about one-fortieth part of the weight, is added ; the juice, on standing, deposites, after this addition, another sediment; from this it is poured off, and the clear liquor is put into bottles, which are to be kept in a cool place. By these proceses, however, much of the active matter is frequently removed, or chemically changed, and the juice is rendered comparatively inert ; and besides it is always liable to decomposition on keeping, from the re-action of the elements of the vegetable matter. This form of preparation is therefore an improper one ; it is rejected, with propriety, from the London and Dublin Pharmacopoeias; and there is only one officinal juice retained by the Edinburgh College, which might also be discarded, as it is never used, nor kept in the shops. It is named Succus cochlearu3 compositus, vulgo Succi ad Scorbuticos. Compound Juice of Scurvy Grass. " Take- of Juice of Scurvy Grass, Juice of Water Cresses from the herbs recently gathered, Juice of the fruit of the Orange, of each two pounds ; Spirit of Nutmeg, half a pound. Mix them, and put aside the liquor until the impurities subside ; then pour it off." This used to be employed as a remedy in scurvy, in the dose of half a pound daily ; but it has long been in total disuse. CHAPTER IV. SUCCI SPISSATA, VULGO EXTRACTA.—INSPISSATED JUICES, COMMONLY NAMED EXTRACTS. The juice expressed from succulent vegetables, frequently holds dissolved, or diffused through it, the principles in which the medicinal powers of the plant n fde. But containing a large proportion of water, and b ing liable to decomposition, the process of inspissation is em- INSPISSATED JUICES. 16 ployed to obtain the active matter in a more concentrated state, and to obviate this spontaneous change he preparations thus obtained are named Inspissated Juices, formerly Extracts. In the greater number of cases, however, this operation cannot be performed without injury to the active matter. Any volatile, principle is necessarily dissipated ; and even where there is no injury of this kind, the vegetable matter, at. the temperature required, suffers decomposition, either from the re-action of its elements, in consequence of which they enter into new combinations, or from the chemical action of the oxygen of the air. Extractive matter, such as that contained in the juices of plants, becomes insoluble from mere exposure to the air, as Vauquelin observed : this change takes place more rapidly at the temperature of boiling water, as Fourcroy has shown; and T. Saussure, who has exmined these changes more minutely, has found that they are accompanied with an absorption of oxvgeu from the air, and a formation of carbonic acid, with probably, likewise, as he inferred, a formation of water, from the union of part of the oxygen and hydrogen of the vegetable matter. Such changes must give rise to alterations in the medicinal powers of these substances, and hence we cannot rely on the activity and uniformity of operation in these inspissated juices Even alter they are prepared too, they must continue to suffer a slow spontaneous decomposition, and hence their activity must diminish with age. From the analysis of these inspissated juices, they appear to contain usually a large proportion of saline matter, principally acetates of potash, lime and ammonia, frequently free acetic acid, and sulphate and muriate of potash, and sulpha e of lime. The directions for preparing the inspissated juices are given in the Edinburgh Pharmacopoeia, under the formula for the first of them, that of Wolfsbane The Dublin College direct, that the juice, after expression, shall remain at rest for six hours, that its feculencies may INSPISSATED JUICES. 17 subside before evaporation. The London College, with more propriety, order it to be evaporated without depuration. Succus spissatus aconiti napelli. Inspissated Juice of Aconite or Wolfsbane. " The fresh leaves of the aconite are to be bruised, and being enclosed in a hempen bag, are to be pressed strongly, that they may give out their juice, which is to be reduced by evaporation in open vessels, heated by boiling water saturated with muriate of soda, to the consistence of thick honey. The mass, after it has cooled, is to be kept in glazed earthen vessels, and moistened with alcohol." This inspissated juice is the form under which wolfsbane was introduced into practice by Storck. He recommended it in glandular swellings, scrofulous and venereal affections, gout, and in obstinate chronic rheumatism, in a dose of half a grain night and morning, and gradually increased to five or six grains. It is very seldom prescribed. In the same manner are prepared the following Inspissated Juices from the leaves of their respective plants. Succus spissatus atropjE belladonje. Inspissated Juice of Deadly Nightshade. This has been recommended by the German practitioners in schirrus, cancer, in epilepsy and mania, in a dose of one grain gradually increased. It retains the peculiar property of the plant, that of occasioning dilatation of the pupil, whence it has also been prescribed in amaurosis. Succus spissatus conii maculati. Inspissated Juice of Hemlock. Under this form, hemlock was employed by Storck in schirrus and cancer. The dose given is at first two grains, but it requires to be quickly increased, and it. Vol. II. 4 INSPISSATED JUICES. 18 has at length been taken to the extent of several drachms in the day. In the preparation of it, the narcotic power of the hemlock seems always to be more or less impaired ; it is also injured by keeping, and we have no other test of its activity than the strength of its narcotic odour. It is therefore inferior to the dried leaves of the plant, which are likewise, however, liable to a considerable degree of uncertainty, according to the manner in which they have been dried and preserved. A common form of exhibition is that of the inspissated juice made into pills by the addition of a sufficient quantity of the powder of the leaves ; but, on the whole, the powder alone is to be preferred, both as being in general more active and uniform, and as we have a test of its proper preparation more certain in the richness of its green colour. Succus spissatus hyoscyami nigri. Inspissated Juice of Black Henbane. This inspissated juice retains a considerable degree of narcotic power, and the plant resembling opium in its operation, it is occasionally employed as a substitute for it. The dose has been usually one grain, which requires to be increased ; two grains are perhaps not more than equivalent to one grain of opium. The tincture has been introduced as a more certain preparation. The London College admit the four preceding Inspissated Juices, giving them the name of Extracts. The Dublin College have inserted those only of Hemlock and Henbane. Succus spissatus lactucjE viros ie. Inspissated Juice of Strongscented Lettuce. Ph. Ed. This plant, though a narcotic, has been principally used as a diuretic. It was recommended as a remedy in dropsy by the German practitioners, in a dose of four or five grains, gradually increased to one or two drachms in twenty-four hours; but in this country it has been little used. INSPISSATED JUICES. 19 Succus spissatus sambucci nigrjE, vulgo Rob Sambuci. Inspissated Juice, or Rob of Elder. The preparation of this juice, as directed in the Edinburgh Pharmacopoeia, is peculiar. " Five pounds of the juice of Elder Berries, and one pound of Sugar, are to be boiled with a gentle heat to the consistence of thick honey." It has been given as an aperient or moderate laxative and diuretic in a dose of half an ounce, or one ounce; but it possesses no quality to recommend it. In the preparation of it in the Dublin Pharmacopoeia, it is merely inspissated without sugar. Succus spissatus momordiCjE elaterii, vulgo Elaterium. Inspissated Juice of Wild Cucumber, or Elaterium. " Cut the ripe fruit of the wild cucumber, and pass through a very line hair-sieve, the juice lightly expressed; boil it a little, and set it aside for some hours, until the thicker parts subside. Pour off the thinner part which floats above, and separate the rest by straining. The thicker part which remains after the straining, being covered with a linen cloth, is to be dried by a gentle heat." Similar directions are given in the Dublin and London Pharmacopoeias, omitting only the boiling,—an omission which is proper, if this substance be a fecula, as has been usually supposed. From the mode of preparation, it is obvious that this consists of a matter which had been suspended in the juice, and hence it has been generally regarded as a species of fecula, without having been, however, very particularly examined. It is a very violent cathartic, operating powerfully in a dose of one or two grains. It has been used as a hydrogogue in dropsy, and as a cathartic in obstinate constipation, where others have failed. The violence, and in some measure the uncertainty of its operation, prevent its frequent use ; and it is seldom even to be found in the shops. FIXED OILS. 20 CHAPTER V. OLE A FIXA SIVE EXPRESSA.—FIXED OR EXPRESSED OILS. Expressed oils are distinguished by their unctuosity and insipidity, by being insoluble in water and in alcohol, by being incapable of volatilization, without change, and by combining with the alcalis, forming soaps. They exist in the fruit and seeds of vegetables, and are obtained by expression, or decoction with water. The former method is in general to be preferred ; and to afford the oil pure it must be performed without heat, which, though it favours the separation of the oil, communicates to it acrimony and an unpleasant flavour. To preserve them from becoming rancid, they ought to be kept secluded from the air, this change being produced in them by absorption of oxygen. A process in Pharmacy somewhat difficult is to mix these oils with any watery fluid, so that they may be conveniently exhibited. It is usually done by the medium of mucilage, or of an alcali. If triturated with mucilage, and a small quantity of sugar, the oil is diffused through the water, and a milky liquor is formed, in which, however, the diffusion is rather imperfect. A combination more complete and permanent is effected, by adding a few drops of water of ammonia, or two or three grains of sub-carbonate of potash. The directions for preparing these oils in the Edinburgh Pharmacopoeia, are given under the Oil of Almonds. Oleum amygdalae communis. Oil of Almonds. " Take of Fresh Almonds any quantity. Bruise them in a stone mortar, inclose them in a hempen bag, and express the oil by a press without heat." The oil thus obtained is the purest of the expressed EMULSIONS. 21 oils, being limpid and entirely free from odour or taste. It is used as a demulcent, and for the general medicinal purposes to which expressed oils are applied. In the same manner is to be expressed Oleum lini usitatissimi, Oil of Lintseed, from the seeds of the plant. Being less pure, it is used only as an external application. Usually, it is prepared on the large scale; and to remove the mucilage, heat is employed. To these the London College add Oleum ricini, Castor Oil, ordering it to be prepared by bruising the seeds, from which the external pellicle has been removed, and expressing the oil without any application of heat. This oil is usually prepared, however, in the West Indies by decoction, and is milder than when obtained by expression. The Olive Oil, Oleum EUROPiEiE, which of all the expressed oils is most largely employed, is imported from the South of Europe. CHAPTER VI. EMULSIONES.—EMULSIONS.—MISTURA.—MIXTURES. Emulsions are preparations in which the expressed oil of the seeds or kernels, from which they are made, is diffused through water by the medium of the sugar, mucilage, and fecula, which the seeds contain. They may be made from lintseed, from the seeds of the poppy, and from other oily seeds: but they are always ordered to be prepared from almonds, as being free from any disagreeable flavour or taste. They are always opaque and milky. As the oil is merely diffused through the water, it gradually separates and rises towards the surface. The fluid beneath is like whey in its appearance, and it soon becomes acescent from the slow fermentation of the saccharine matter. The addition of vinous spirits, or of any weak acid, decomposes emul- EMULSTONS. 22 sions, separating the oil. In prescribing them, therefore, it is necessary to avoid combining with them any tincture, or any substance having acidity. Emulsio amygdalje communis. Almond Emulsion. (Mist. Amygdalae, Ph. Lond. —Lac. Amygdal. Dub.) " Take of Sweet Almonds, one ounce; Water, two pounds and a half; beat the blanched almonds carefully in a stone mortar, adding the water gradually, then strain." The almonds are blanched, or freed from their thin rind, by keeping them a minute or two in boiling water, when the rind is easily detached. They require to be well beat as the water is added. The emulsion is used as a diluent and demulcent in catarrh and gonorrhoea, or during the application of a blister, being drunk ad libitum, and it is more grateful than any other preparation. Emulsio gummi mimosjE nilotica, vulgo Emulsio Arabica. Arabic Emulsion. (Emulsio Arabica, Ph. Dub.) " This is made in the same manner, adding, while beating the almonds, two ounces of mucilage of gum Arabic." It is used in the same cases as the preceding, and from the addition of the mucilage is supposed to have rather more demulcent power. Emulsio camphorata. Camphor Emulsion. " Take of Camphor, one scruple; blanched Sweet Almonds, two drachms; Refined Sugar, one drachm; Water, six ounces: Let it be made in the same manner as the Almond Emulsion." Camphor is less apt to occasion nausea or uneasiness at the stomach when given in a liquid than when in a solid form; and this is one of the best forms of preparation, the camphor being completely diffused. Its dose is two ounces, but as this narcotic is not much employed internally in modern practice, the camphor emulsion is not often prescribed. MIXTURES. 23 MISTURA.—MIXTURES. To the preparations named Emulsions, the London College have extended the general name of Mixture, which is employed in Pharmacy to denote those preparations in which different ingredients are mingled together in the liquid form, or in which solid substances are diffused through liquids by the medium of mucilaginous or saccharine matter. And under this name of Mixture are inserted several compound medicines, both in the London and Dublin Pharmacopoeia, of which it is necessary to take notice. Some of these had formerly a place in the Edinburgh Pharmacopoeia ; but they have been discarded, probably from the consideration that they must always be prepared extemporaneously, and may therefore be varied according to the intention of the prescriber. Mistuka ammoniaci. Gum Ammoniac Mixture. Ph. Lond. (Lac Ammoniac. Ph. Dub.) " Take of Gum Ammoniac, two drachms ; Water, half a pint. Triturate the Ammoniac with the water poured on it gradually until they are intimately mixed." In the Dublin Pharmacopoeia, one drachm of Gum Ammoniac is diffused by trituration in eight ounces of Pennyroyal Water, and the mixture is strained through a linen cloth. In these mixtures the resinous matter is suspended in the water by the medium of the gum. and a milky liquor is formed. From this the resin subsides slowly. Under this form this gum-resin is sometimes prescribed as an expectorant, the dose of the mixture being from half an ounce to an ounce. Mistura assafoetidje. Assafoetida Mixture. Ph. Lond. (Lao Assafcetida?, Ph. Dub.) " Take of Assafoetida, two drachms ; Water, half a pint. Rub the assafoetida with the water a ided gradually until they are perfectly mixed." In the Dublin Pharma 24 MIXTURES. copoeia, one drachm of Assafoetida is diffused by trituration in eight ounces of Pennyroyal Water. The resin of the assafoetida is in this mixture likewise suspended in the water by the medium of the gum. It is a form under which this foetid drug is prescribed in the hysteric paroxysm, from half an ounce to an ounce being given and repeated at short intervals. Mistura camphors. Camphor Mixture. Ph. Lond. (Mistura Camphorata, Ph. Dub, " Take of Camphor, half a drachm ; Rectified Spirit, ten minims ; Water, a pint. Rub the camphor first with the spirit, then add the water gradually, and'strain." In the Dublin Pharmacopoeia, the preparation is a little different; one scruple of Camphor being rubbed with ten drops of rectified spirit; half an ounce of refined sugar being added, and a pound of water, and the liquor being strained through a linen cloth. Boiling water was formerly ordered in making this mixture, by which much of the camphor was volatilized, and very little dissolved. Even at a low temperature, the water scarcely dissolves any appreciable quantity, and it can be regarded only as receiving odour and some degree of taste, without any such impregnation as shall communicate to it medicinal efficacy. Mistura cornu usti. Mixture of burnt Horn. Ph. Lond. (Decoctum Cornu Cervini. Decoction of Hartshorn, Ph. Dub.) " Take of Burnt Horn, two ounces ; Gum Arabic in powder, one ounce ; Water, three pints. Boil down to two pints, stirring constantly ; then strain." This is an absurd preparation, introduced at a time when the principles of Pharmacy were nearly unknown, and retained merely from the influence of habit. The burnt hartshorn, (which is chiefly phosphate of lime), is perfectly insoluble in water; the gum alone therefore is dissolved; the hartshorn, by the continued boiling, is diffused, and kept suspended by the mucilaginous liquid ; but this might equally be done without this ope- MIXTURES. 25 ration ; and when done it can communicate to the preparation no medicinal power. Mistura cret.e. Chalk Mixture. Ph. Lond. and Dub. " Take of Prepared Chalk, half an ounce; Refined Sugar, three drachms; Gum Arabic in powder, half an ounce; Water, a pint. Mix them." The chalk is in this mixture suspended by the mucilage ; it is taken as an antacid in the dose of one or two ounces occasionally ; but it may be doubted whether the mucilage and sugar will not rather be injurious in that state of the stomach which generates acidity. Mistura ferri comfosita. Compound Mixture of Iron. Ph. Lond. " Take of Myrrh in powder, one drachm; Sub-carbonate of Potash, twenty-five grains; Rose Water, seven fluid ounces and a half; Sulphate of Iron in powder, one scruple ; Spirit of Nutmeg, half a fluid ounce ; Refined Sugar, a drachm. Rub the myrrh with the sub-carbonate of potash and the sugar, and, during the rubbing, add first the rose water, and the spirit of nutmeg, and afterwards the sulphate of iron. Put the mixture immediately into a proper glass vessel, which stop closely." This, with a few trivial alterations, is the celebrated Antihectic Mixture of Griffith; which, as first invented, was undoubtedly an unchemical mixture, the prescriber not being aware of the changes produced in the active ingredients by their mutual action, but which, in practice, was found possessed of peculiar advantages. The sulphate of iron, it is obvious, is decomposed by the sub-carbonate of potash, the sulphuric acid combining with the potash, while the carbonic acid unites with the oxide of iron. The carbonate of iron which is formed is diffused in the mixture along with the myrrh, and both are probably kept more completely suspended by an excess of alcali. This chalybeate proves much less irritating than the sulphate of iron, producing no unpleasant effect on the stomach, and at the same time it Vol. IL 5 26 MIXTURES. is more active than the common carbonate or rust of iron, in which the iron is at the maximum of oxidation, while, in the present preparation, it is at the minimum, is in a different state of aggregation, and probably combined with a larger quantity of carbonic acid. To preserve it in this low state of oxidation, it is ordered to be kept in a bottle closely stopped ; but as iron has a strong tendency to pass to a more highly oxidated state, and suffers this change very rapidly from the action of the air, it is preferable that the preparation should be always extemporaneously made. Griffith's Mixture was employed as a remedy in hectic fever, in chlorosis, and other diseases in which iron is given as a tonic. The mixture of the London Pharmacopoeia, which is nearly of the same strength, may be given in the same cases in a dose of an ounce once or twice a day. Mistura guaiaci. Guaiac Mixture. Ph. Lond. " Take of the Gum-Resin of Guaiac, a drachm and a half; Refined Sugar, two drachms ; Mucilage of Gum Arabic, two fluid drachms; Cinnamon Water, eight fluid ounces. Rub the guaiac with the sugar, then with the mucilage, adding gradually, while these are rubbed together, the cinnamon water." This may be a convenient form, for the exhibition of guaiac, though there appears to be no great advantage in multiplying these extemporaneous prescriptions. Mistura moschi. Musk Mixture. Ph. Lond. " Take of Musk, Gum Arabic, Refined Sugar, of each one drachm ; Rose Water, six fluid ounces. Rub the musk with the sugar, then with the gum, and add gradually the rose water." The same observation applies to this as to the preceding preparation. Its dose, when it is prescribed, is an ounce, or an ounce and a half. INFUSIONS. 27 CHAPTER VII. INFUSA.—INFUSIONS. Infusion is a general term, which might be applied to that process by which the soluble parts of any solid are extracted by the action of any fluid kept in contact lor some time with the body on which it acts. In Pharmacy it is usually limited to that case where the active matter of vegetable substances is extracted partially or completely by water, though it is sometimes extended to the same process where other liquors, as alcohol, are employed. It is in the former sense, as denoting an aqueous preparation, that the term is used in the Pharmacopoeias ; and Infusions are solutions of vegetable matter in water obtained by maceration. Several -of the proximate principles of vegetables being soluble in water, they can often, by this operation, be extracted with advantage. But there are others with regard to which it is altogether useless. Thus the purgative quality of rhubarb is extracted by infusion in water: even the cathartic powder of senna, though it appears to reside in a principle more peculiarly soluble in alcohol, is still obtained by the action of water, when a large quantity is employed, and its solvent power is promoted by heat. But the power of jalap is scarcely obtained, the watery infusion of it being comparatively weak. In prescribing infusions, therefore, regard must always be had to the composition of the substances ordered to be infused. In general, mucilaginous plants yield their mucilage readily to water: bitterness and astringency are also usually 'extracted by water with facility, and the aromatic quality where this resides in an essential oil. With regard to other properties, scarcely any general rule can be delivered. The quantity and quality of the matter extracted by infusion, are considerablv varied by the temperature of INFUSIONS. 28 the fluid. Infusions made with warm water, are considerably stronger than those made with cold ; in some cases, however, especially with respect to bitters, they are less grateful. In the Bitter Infusion, therefore, of the Edinburgh Pharmacopoeia, cold water is directed to be used; in all the others, boiling water is ordered to be poured on the materials of the infusion, and the vessel is generally placed near a fire. It is rather singular, that dried vegetables yield their virtues to water by infusion, more readily than when they are in the recent state, probably from the vegetable matter being more easily penetrated by the water. Infusions are always injured by keeping. Though at first transparent, they soon become more or less turbid ; they deposite a mucous-like substance ; lose their peculiar taste, and after some time acquire a putrid smell, — changes owing to the gradual decomposition of the vegetable matter they hold dissolved. Infusions are therefore never kept ready prepared in the shops ; they are to be regarded as extemporaneous preparations, which, in general, require several hours before they can be prepared. Infusum cinchona officinalis. Infusion of Peruvian Bark. (Infus. Cinchonas, Ph. Lond. Dub. " Take of Peruvian Bark in powder, one ounce ; Water, one pound. Macerate them for twenty-four hours, and strain." The formula, as given in the other Pharmacopoeias, is nearly the same, only that boiling water is ordered to be poured on the bark, by the London College, while by the Dublin College the maceration is without heat. By infusion, water is capable of dissolving only a small portion of the active matter of bark, and the preparation therefore cannot be regarded as having much activity. It is used principally as a bitter in dyspepsia, in a dose of two ounces occasionally. INFUSIONS. 29 Infusum digitalis purpurea. Infusion of Foxglove. (Infus. Digital. Ph. Lond. 44 Take of the dried leaves of Foxglove, one drachm; Boiling Water, eight ounces: Spirit of Cinnamon, one ounce. Macerate for four hours, and strain." Infusion is the form under which Dr. Withering, who introduced the use of digitalis in dropsy, recommended it to be given, and it is on the whole the best form under which it can be given, with the view at least to obtain its diuretic operation. The above is the formula of Withering, and it has likewise been received with no essential difference into the London Pharmacopoeia. Its dose is an ounce taken twice a day, and continued until the effects of the remedy appear. Infusum gentians luteje compositum, vulgo Infusum Amarum. Compound Infusion of Gentian. (Infus. Gentianaj, Ph. Lond. Dub.) 44 Take of Gentian Root cut, half an ounce; Dried Orange-Peel bruised, one drachm; Coriander Seeds bruised, half a drachm; Diluted Alcohol, four ounces; Water, one pound. First pour on the alcohol, and after three hours the water; then macerate without heat lor twelve hours, and strain." This bitter infusion is employed in dyspepsia: a sufficient quantity of alcohol is added to aid the solvent power of the water, and to preserve the infusion from spontaneous decomposition, while there is not so much as to give spiritous pungency. It is therefore better adapted to continued use than the bitter tinctures. Its dose is two ounces occasionally. The Dublin College have a similar preparation, under the same name. The London College omit the alcohol; and in an infusion which may be always extemporaneously prepared, and does not therefore require to be long kept, this is perhaps preferable, as avoiding the pernicious consequences arising from the stomach being accustomed to the stimulus of ardent spirit. INFUSIONS. 30 Infusum mimosa; Catechu, vulgo Infusum Japonicum. Infusion of Catechu. (Infus. Catechu, Ph. Lond.) " Take of Extract of Catechu in powder, two drachms and a half; Bark of Cinnamon bruised, half a drachm; Boiling Water, seven ounces; Simple Syrup, one ounce. Macerate the extract and bark with the water in a closed vessel for two hours, then strain and add the syrup." The Extract of Catechu is entirety soluble in water. This preparation, therefore, possesses all its virtues unimpaired, and rendered more grateful, by the addition of the cinnamon. Hence it is one of the best forms under which catechu can be prescribed, its principal use is in diarrhoea: dose, one ounce every third or fourth hour. A small quantity of tincture of opium is frequently added to it with advantage. Infusum uiiei palmati. Infusion of Rhubarb. Infus. Rhei, Ph. Lond.) ' : Take of the Root of Rhubarb bruised, half an ounce; Boiling Water, eight ounces; Spirit of Cinnamon, one ounce. Macerate the root with the water in a. closed vessel for twelve hours, then, adding the spirit, strain the liquor." The infusion of rhubarb is supposed to have more of the purgative than of the astringent power. It is accordingly used as a mild cathartic, in a dose of two or three ounces. There appears to be an unnecessary waste of rhubarb in the proportions ordered; and the formula in the London Pharmacopoeia, in which only a drachm of rhubarb is ordered to eight ounces of water, is preferable, as this will probably afford as much active matter as the water can dissolve, or at least give an infusion sufficiently strong. Infusum ros,e gallice. Infusion of R.ed Rose. " Take of the Dried Petals of the Red Rose, two ounces; Boiling Water, five pounds; Sulphuric Acid, one drachm; Refined Sugar, two ounces. Macerate the petals with the boiling Water in an earthen vessel, which INFUSIONS. 31 is not glazed with lead, for four hours; then having poured on the acid, strain the liquor, and add the sugar." This infusion, which has a place in all the Pharmacopoeias, is used principally as a moderately astringent gargle, in slight cases of cynanchc, or to check salivation. It owes little else than colour, and a pleasant Jlavour, to the petals of the rose ; the astringency depending almost entirely on the sulphuric acid. Infusum tamarindi indicjS cum cassia senna;. Infusion of Tamarind and Senna. (Infus. Setmae cum Tamarindis, Ph. Dub. " Take of the Prepared Fruit of the Tamarind, one ounce; Senna Leaves, oue drachm; Coriander Seeds, half a drachm; Unrefined Sugar, half an ounce; Boiling Water, eight ounces. Macerate them in a close earthen vessel, which is not glazed with lead, shaking frequently, and after four hours strain the liquor. It may be made also with double or triple the quantity of senna." A similar formula is inserted in the Dublin Pharmacopoeia, Cardamom being substituted for coriander seeds. This combination affords a very pleasant purgative, mild in its operation. The whole quantity may be taken at intervals as a dose. If a more powerful cathartic is indicated, it may be made with an increased proportion of senna. The direction of not infusing the materials in a vessel glazed with lead, ought to be attended to, as the acid of the tamarinds acting on the lead, the infusion might receive a noxious impregnation. There are some Infusions peculiar to the London and Dublin Pharmacopoeias, which may be noticed. Infusum anthemidis. Infusion of Chamomile. Ph. Lond. " Take of Flowers of Chamomile, two drachms; Boiling Water, half a pint. Macerate them for ten minutes in a vessel lightly closed ? and strain." INFUSIONS. 32 Under the form of infusion, chamomile is used as a bitter in dyspepsia: it is more grateful when prepared with cold water, and is then equal perhaps to any other bitter. Infusum armoraci,e cojirosiTUM. Compound Infusion of Horse- Radish. Ph. Lond. " Take of Horse-Radish Root, fresh and cut, Mustard Seed bruised, of each one ounce; Boiling Water, a pint. Macerate them for two hours in a vessel lightly closed, and strain; then add, of Compound Spirit of Horse-Radish, a fluid ounce." Under this form the horse-radish may be prescribed in the diseases in which it is employed, more particularly as a stimulant in chronic rheumatism, paralysis, and some forms of dropsy. Its dose is two ounces twice a day. Infusum aurantii compositum. Compound Infusion of Orange-Peel. Ph. Lond. "Take of dried Rind of the Orange, two drachms; of the fresh Rind of the Lemon, one drachm; of Cloves bruised, half a drachm; Boiling Water, half a pint. Macerate for a quarter of an hour in a vessel lightly closed, and strain." This affords a bitter, grateful and somewhat pungent, which may be employed with advantage in some forms of dyspepsia. Its dose is two ounces. Infusum columba;. Infusion of Colombo. Ph. Lond. " Take of Colombo Root, cut, one drachm ; Boiling Water, half a pint. Macerate for two hours in a vessel lightly closed, and strain." The active matter of Colombo is rather imperfectly extracted by water; and this can be regarded only as a bitter infusion, which, like other bitters, may be used in dyspeptic affections. Its dose is two ounces. INFUSIONS. 33 Infusum caryophyllorum. Infusion of Cloves. Ph. L. " Take of Bruised Cloves, a drachm ; Boiling Water, half a pint. Macerate for two hours in a vessel lightly closed, and strain." The aromatic odour and pungency of the clove are extracted in this infusion : it may be used with advantage as a warm and grateful stimulant in some forms of dyspeptic affection, where a sensation of cold and uneasiness is felt at the stomach—a state which is often produced where the habit of taking spirituous cordials has been indulged in. Infusum cascarillac. Infusion of Cascarilla. Ph. L. " Take of Cascarilla Bark bruised, half an ounce; Boiling Water, half a pint. Macerate for two hours in a vessel lightly closed, and strain." Cascarilla is a substance little valued in modern practice, and there does not appear to be much propriety in the introduction of this infusion as an officinal preparation. Its dose is two ounces. Infusum cusparia. Infusion of Angustura. Ph. Lond. " Take of the Bark of Angustura, bruised, two drachms ; Boiling Water, half a pint. Macerate for two hours, in a vessel lightly closed, and strain." The same remark nearly applies to this preparation, as to the preceding one. Under this form, however, angustura may be occasionally used as a remedy in dyspepsia. The dose is two ounces. Infusum lini. Infusion of Lintseed. Ph. Lond. "Take of Lintseed bruised, one ounce; Liquorice Root cut, half an ounce ; Boiling Water, two pints. Macerate for four hours, nigh the fire, in a vessel lightly closed, and strain." The mucilaginous matter of lintseed is very readily dissolved by tepid water ; and this forms a demulcent liquor, often taken with advantage in gonorrhoea, dy- INFUSIONS. 34 suria, and sometimes in catarrh. It is rendered rather more grateful by the addition of a little lemon juice, and of the rind of the lemon. Infusum quassia;. Infusion of Quassia. Ph. Lond. " Take of the wood of Quassia cut, one scruple ; Boiling Water, half a pint. Macerate for two hours, in a vessel lightly closed, and strain." Quassia is a very pure bitter, and its bitterness is extracted by water. Under this form it has been used as a remedy in dyspepsia. Infusum senrje. Infusion of Senna. Ph. Lond. " Take of Senna leaves, an ounce and a half; Ginger, one drachm ; Boiling Water, a pint." Under this form Senna may be given as a purgative, the dose being three or four ounces. It is however less grateful than the infusion of senna and tamarinds of the Edinburgh Pharmacopoeia. The proportion of senna, too, appears to be considerably greater than what is necessary ; and there is no propriety in preparing more of the infusion than what is required for a dose. A similar infusion, in which this is avoided, and in which cardamon seeds are substituted for ginger, has a place in the Dublin Pharmacopoeia. Infusum simarouba;. Infusion of Simarouba. Ph. Lond. " Take of the Bark of Simarouba bruised, half a drachm ; Boiling Water, half a pint. Macerate for two hours, in a vessel lightly closed, and strain." Simarouba yields its bitterness to water; the infusion, however, is inferior to that of quassia, and does not appear to have any particular advantage to recommend it. Infusum tabaci. Infusion of Tobacco. Ph. Lond. " Take of the Leaves of Tobacco, one drachm ; Boiling Water, a pint. Macerate for an hour, in a vessel lightly closed, and strain." MUCILAGES. 35 This infusion is prepared of that strength, proper for giving tobacco under the form of enema, as a narcotic in incarcerated hernia, or to produce evacuation from the intestines, in ileus and obstinate constipation. Infusum menthje compositum. Compound Infusion of Mint. Ph. Dub. " Take of the Leaves of Spearmint dried, two drachms ; Boiling Water as much as is sufficient to form six ounces of infusion when strained. Digest them for half an hour in a covered vessel ; strain the liquor when cold, and add to it, of Refined Sugar, two drachms ; Oil of Spearmint three drops, dissolved in half an ounce of compound tincture of cardamom " This is a grateful stomachic, which may be used to obviate flatulence, or to cover the taste of unpleasant medicines. Infusum Valeriana;. Infusion of Valerian. Ph. Dub. " Take of the Root of Valerian, in coarse powder, two drachms ; Boiling Water, seven ounces. Digest for an hour, and strain the liquor when it is cold." Valerian is frequently taken in hysteric affections under the form of infusion, and this will afford a preparation of proper strength. Its dose is from one to two ounces. CHAPTER VIII. OF MUCILAGES. The term Mucilage, understood as denoting a particular preparation in Pharmacy, is applied to solutions of gummy matter in water, sufficiently concentrated to have a certain degree of viscidity ; or to similar solutions 36 MUCILAGES. obtained by the maceration of water on vegetables, in which this kind of matter abounds. They are principally employed as vehicles for other substances, either to suspend powders in liquids, to diffuse oils or resinous mat ter in water, or to give form and tenacity to pills. Mucilago amyli. Starch Mucilage. (Mucilago Amyli, Thar. Lond. Dub.) " Take of Starch, half an ounce ; Water, one pound. Rub the starch, with the water gradually added to it, then boil them for a short time. Starch is the fecula of wheat, and though perfectly insoluble in cold water, is dissolved by boiling water, and forms a gelatinous solution. This starch-mucilage is principally used as a vehicle for giving opium under the form of enema. Mucilago astragali tra6Acantha3. Mucilage of Gum Tragacanth. (Mucilag. Gum. Trag. Ph. Dub.) " Take of Gum Tragacanth beat to powder, one ounce; Boiling Water, eight ounces. Macerate for twenty-four hours, and rub the gum carefully, that it may be dissolved ; then strain through linen." In the Dublin Pharmacopoeia, the proportions are two drachms of tragacanth to eight ounces of water. Tragacanth is not easily dissolved in water, and, even with the aid of heat, the viscid mucilaginous liquor that is formed remains turbid and flocculent. The proportion of the gum to the water is rather large in the Edinburgh Pharmacopoeia, but it is designed to form a stiff mucilage, to be used principally in making troches. Mucilago mimosas nilotica;. Mucilage of Gum Arabic. (Mucilago Acaciae, Ph. Lond. —Mucilago Gum. Arab. Ph. Dub.) il Take of Gum Arabic in powder, one part ; Boiling Water, two parts. Digest with frequent agitation until the gum be dissolved ; then strain through linen." Mucilage of Gum Arabic is sometimes employed as a demulcent, being the basis of the common pectoral DECOCTIONS. 37 mixtures used in catarrh. It is more generally used as an agent in Pharmacy, to suspend in water substances insoluble in that liquid, diffuse oils in water, and for similar purposes. CHAPTER IX. OF DECOCTIONS. The power of water as a solvent, is, like that of all other chemical agent's, increased by heat. Hence, in general, the active matter of vegetable substances is more completely extracted by boiling them with water, than by mere infusion, either cold or warm, the residuum in the one case being found more inert than in the other. It is not to be concluded, however, from this fact, that the decoction is proportionally more active. On the contrary, though the water extracts the active matter of the substance, it is often much injured in the operation ; in few cases is the decoction equal in power to the quantity of the substance from which it is prepared ; in many it is much impaired ; and in some it is totally lost, the decoction itself and the residual matter being both nearly inert. This change is often owing to the dissipation of the volatile principles of the substance operated on. All the essential oils are volatilized at the temperature of boiling water. It is evident, therefore, that substances, whose virtues depend wholly or in part on their essential oil, must be injured by this operation : for this reason, aromatics are always useless additions to decoctions; and the aromatic flavour of many active substances is also lost in this form of preparation. But there are many cases in which the virtues of medicines are injured by decoction, in which we cannot ascribe the injury to the mere dissipation of their active principles. Opium, bark, and ipecacuan, for instance, are much 38 DECOCTIONS. weakened by boiling in water ; yet, when the operation is conducted in close vessels, so as to collect the water that is evaporated, that water is not found to be strongly impregnated with the active matter of the substance operated on. The distilled water of opium has been given to the extent of six ounces, without exerting any great narcotic effect; and the distilled water of ipecacuan, though it proves emetic, is much less so than the simple infusion Since, then, the active master is neither to be found in the fluid which is evaporated, nor in that which remains, it is evident that it must have been destroyed in the operation, by decomposition of the principles on which it depended. It is accordingly found that some such change is induced. When a decoction is strained, so as to be obtained transparent, and is subjected anew to boiling, it acquires a deeper colour, becomes turbid, an insipid substance being gradually formed, which is deposited. This change may be owing, either to the reaction of the elements of the vegetable matter being favoured by the humidity, and the high temperature, so that they enter into new combinations, or to the action of the air upon it imparting oxygen. There have been experiments brought in proof of this last circumstance taking place in some cases, especially in the decoction of Peruvian bark, oxygen being absorbed, combining with the extracto-resinous matter, and forming an insipid substance- This in particular is affirmed by Fourcroy. And it is farther rendered probable by the experiments of the younger Saussure, who found that extractive matter, in a humid or dissolved state, exposed to the air, was precipitated after a few days in an insoluble state, and oxygen was absorbed ; carbonic acid was also formed ; and he concluded, from the results he obtained, that, while part of the carbon of the vegetable matter is abstracted by the action of the oxygen of the air, part also of its oxygen and hy drogen combine and form water, so that the residual matter has an increased proportion of carbon. These changes will be favoured by a high temperature; they are those, therefore, proba- DECOCTTONS. 39 bly that take place in decoction, and impair or destroy the powers of the vegetable substance ; though it is also possible, that chemical changes may arise from the reaction of the elements of the vegetable matter itself, independent of any action of the air. From these observations, it is evident, that decoction can seldom be a proper form for the administration of medicines. The pungency and aromatic flavour, on which part of their virtues depends, and which renders them at least more grateful, must always be impaired or lost, and their more important virtues must often be equally injured. It is accordingly a form which is not now often applied to active remedies. Decoctions, like infusions, are extemporaneous prescriptions. They cannot be kept ready prepared, as in a few days they are injured, and run into the acetous fermentation. They can, however, be prepared much sooner than infusions; the boiling not requiring to be continued in general for more than ten or fifteen minutes. They ought to be strained while hot, as, on cooling, a portion of the dissolved matter is frequently deposited, which is as active as that which remains dissolved, and this precipitate ought to be mingled with the liquid by agitation, when the dose is to be taken. Decoctum althjeje officinalis. Decoction of Althaea. i( Take of Dried Althaea Root bruised, four ounces: Raisins freed from their seeds, two ounces ; Water, seven pounds Boil to five pounds; put aside the strained liquor until the impurities have subsided, and pour off the clear liquor." The gummy part of vegetables is less injured by decoction than any other. In this decoction, therefore, all the powers of the althaea root are obtained, and it is under this form that it is used. The decoction is taken as a demulcent, to the extent of two or three pounds in the day, in nephritic complaints, in ardor urinae, and sometimes in catarrh. 40 DECOCTIONS. Decoctum anthemidis nobilis, vulgo Decoctum Chamcemeli sive Commune. Decoction of Chamomile, or Common Decoction. " Take of the Dried Flowers of Chamomile, one ounce; Caraway seeds bruised, half an ounce ; Water, five pounds. Boil for a quarter of an hour, and strain." This decoction is used only as an enema, and as a fomentation. When applied to the former purpose, the effect it may produce is to be ascribed principally to the water ; in the second, the vegetables are not more useful, except as retaining longer the heat and moisture when applied to a part. There is a similar preparation in the Dublin Pharmacopoeia, under the name of Dkcocium Chamcemeli Compos it um, in which half an ounce of the flowers of chamomile and two drachms of fennel seeds are boiled in a pound of water. It is designed for the same purposes ; and as an enema it is rendered more active, in the preparation named Enema Catharticum, by dissolving in ten ounces of it an ounce of manna, and half an ounce of sulphate of magnesia, adding an ounce of olive oil. When to this are added two drachms of tincture of assafoetida, it forms the preparation of the same Pharmacopoeia named Enema Foetidum. Decoctum cinchonas officinalis, vulgo Decoctum Corticis Peruviani. Decoction of Peruvian Bark. (Decoct. Cinchona?. Ph. Lond. Dub.) M Take of Peruvian Bark in powder, one ounce ; Water, one pound and a half. Boil for ten minutes in a covered vessel and strain the liquor while hot." The resino-extractive matter of Peruvian bark is altered by decoction ; hence the reason of the directions given in the Pharmacopoeia under this preparation, the boiling not being continued longer than ten minutes, as in this time the active matter, it is supposed, will be as fully extracted as it would be by longer boiling, and the decoction being performed in a covered vessel to exclude as much as possible the access of the air, to the chemical agency of which the change in the DECOCTIONS. 41 extractive matter has been supposed owing. The liquor is ordered to be strained while hot, as it holds dissolved a larger portion of the resinous matter than it can retain in solution when cold. Hence, after having been strained, it becomes turbid as it cools, depositing a reddish precipitate. This ought to be mixed with it by agitation when the dose is to be taken. The addition of a little acid causes it to remain dissolved, and where this can be prescribed with propriety it may be employed. Decoction of bark is used in those cases which require the free administration of the remedy, but in which in substance it sits uneasy on the stomach. The dose is two or three ounces, taken as often as the stomach will receive it. Decoctum daphnes mezerei. Decoction of Mezereon. " Take of the Bark of the Root of Mezereon, two drachms; of Liquorice Root bruised, half an ounce; Water, three pounds. Boil with a gentle heat to two pounds, and strain." A compound decoction, prepared from guaiac wood, sarsaparilla, sassafras, mezereon and liquorice, had been highly celebrated, under the name of Lisbon Diet Drink, for its efficacy in the treatment of symptoms connected with syphilis, particularly thickening of the ligaments, affections of the bones and periosteum, and obstinate ulceration. Dr. Russell, from a series of experiments, concluded, that the mezereon is the ingredient on which its activity depends; and this decoction, in which the liquorice serves merely to cover the pungency of the mezereon, has been substituted for the more complicated composition. It is used in the same cases, sometimes also in cutaneous affections, the dose being from four to six ounces twice or thrice a-day. In a large dose, it is liable to excite nausea. Vol. II. 7 DECOCTIONS, 42 Decoctum geoffbjea; inermis. Decoction of Cabbage-Tree Bark. " Take of Cabbage-Tree Bark in powder, one ounce; Water, two pounds. Boil with a gentle heat to one pound, and strain." This decoction is the form under which this medicine has been usually administered, the bark in substance being too violent in its operation. In the West India Islands, the decoction has been used as a very effectual remedy in worms, especially the lumbrici. The dose given is two ounces to an adult; if this occasion nausea, griping, or tenesmus, which it sometimes does, these symptoms are relieved by a dose of castor oil. In this country it has not been much employed. Decoctum guajaci officinalis compositum, vulgo Decoctum Lignorum. Compound Decoction of Guaiac. " Take of Guaiac Wood Shavings, three ounces; Raisins, two ounces ; Sassafras Root cut, Liquorice Root bruised, of each one ounce ; Water, ten pounds. Boil the water with the guaiac wood and raisins, on a gentle fire, to five pounds, adding the roots towards the end of the boiling; then strain without expression." This decoction derives its virtues principally from the guaiac. It acts as a diaphoretic, and has been used in cutaneous diseases, and in chronic rheumatism, taken in the quantity of a pound twice or thrice a-day. It has also been employed in the treatment of obstinate venereal symptoms, especially as an auxiliary to mercury. Decoctum hordei distichi. Decoction of Barley. (Decoct. Hordei, Ph. Lond. Dub.) "Take of Pearl Barley, two ounces; Water, five pounds. First wash off with cold water the flour adhering to the barley; then boil the barley for a short time with about half a pound of water, to extract the colouring matter. This being rejected, put the barley thus purified into five pounds of boiling water. Boil this to one half, and strain." DECOCTIONS. 43 This decoction is never prepared in the shops. It is, however, very extensively used as a diluent in febrile diseases; and as it is of some importance that it should be grateful, it has been judged proper to give directions how it may be best prepared. Similar directions are given by the London and Dublin Colleges; and they have also inserted another composition, under the name Decoctum Hordei Compositum, in which raisins, figs, and liquorice root are boiled with the barley,—additions which probably render it rather cloying to the taste and stomach, and from which no great advantage can be derived. Decoctum polygala: senega:. Decoction of Seneka. (Decoct. Senegas, Ph. Lond.) " Tfake of Seneka Root, one ounce; water, two pounds. Boil to sixteen ounces, and strain." Under the form of decoction, senega has been employed as an expectorant in pneumonic affections, attended with accumulation of mucus in the bronchia?, and. as a diaphoretic in chronic rheumatism ; and though not much used, a formula similar to this has been introduced, into the last edition of the London Pharmacopoeia. The dose is two or three ounces three or four times a-day. Decoctum smilacis sarsaparilla;. Decoction of Sarsaparilla. (Decoct. Sarsaparilla, Ph. Lond. Dub.) " Take of Sarsaparilla Root cut, six ounces; Water, eight pounds. Digest for two hours, in a temperature of about 195°, then take out the root and bruise it; put it again into the liquor, and boil it with a gentle fire to two pounds; then express it, and strain." The fecula, which is the principle in which the power of sarsaparilla resides, is not easily extracted merely by boiling the root. This is the reason of the particular directions to digest the root first, and then bruise it; it is thus softened, and yields its soluble matter more readily in the subsequent boiling. This decoction is thf* DECOCTIONS. 44 form under which sarsaparilla is always given, its dose being from a pint to a quart in the course of the day. It has been used in venereal cases, either to promote the action of mercury, or to remove symptoms which have remained after a long continued mercurial course. Dr. Fordyce celebrated its efficacy in very high terms, in giving relief in nocturnal pains, removing eruptions, and as being the best restorative in the emaciation and debility remaining after the long continued use of mercury. Its efficacy in these affections has probably been overated, and the opinion is perhaps more just which regards it only as belonging to the nutrientia, or as a mere demulcent. The benefit sometimes derived from it has perhaps as frequently arisen from the exhibition of mercury too long continued having been suspended, as from any action of the sarsaparilla itself. The decoction has been used with considerable advantage as a demulcent in dysuria and morbid irritability of the bladder, occasioning incontinence of urine. A few Decoctions, peculiar to the London and Dublin Pharmacopoeias, remain to be noticed. Decoctum aloes compositum. Compound Decoction of Aloes. Pharm. Lond. " Take of Extract of Liquorice, half an ounce; Subcarbonate of Potash, two scruples; Extract of Aloes, Myrrh in powder, Saffron, of each one drachm; Water, a pint. Boil down to twelve fluid ounces, and strain, then add of Compound Tincture of Cardamoms, four fluid ounces." The gum resinous substances in this decoction are retained in solution, partly by the solvent power of the water, and partly by the action of the alkali; and by the addition of the spiritous tincture, any spontaneous decomposition will be more effectually prevented. The composition is newly introduced into the Pharmacopoeia, DECOCTIONS. 45 and is said to be analogous to one in use, under the name of Beaume de Vie. It is one which must be very nauseous, and it is not obvious what peculiar advantage can belong to it. As a stimulating aperient, it may be given in the dose of two ounces. Decoctum cydonias. Decoction of Quince Seeds. Pharm. Lond. " Take of Quince Seeds, two drachms; Water, a pint. Boil with a gentle heat for ten minutes, then strain." Quince seeds abound with mucilage, which is extracted easily by boiling in water. It is liable to spontaneous decomposition, and having no peculiar advantage is little employed. Decoctum dulcamara:. Decoction of Woody Nightshade. Pharm. Lond. " Take of the Stalks of Woody Nightshake cut, one ounce; Water, a pint and a half. Boil to a pint, and strain." Under this form the woody nightshade may be employed ; but there seems no propriety in giving a formula for its preparation, more than any other vegetable substance, which may be given under the same or any similar form. Decoctum lichenis. Decoction of Iceland Liverwort. Pharm. Lond. and Dub. " Take of Liverwort, one ounce ; Water, a pint and a half. Boil down to one pint, and strain." In the Dublin Pharmacopoeia, a digestion of the w ater on the lichen for two hours is ordered, and then boiling for a quarter of an hour. The fecula or mucilage of the lichen is extracted by water by boiling, and it is under this form of decoction that it has been employed as a demulcent, and a mild nutritious substance easy of digestion. DECOCTIONS. 46 Decoctum malvje composptum. Compound Decoction of Mallow. " Take of Mallow dried, one ounce; Chamomile Flowers dried, half an ounce; Water, a pint. Boil them for a quarter of an hour, and strain." This decoction is designed for the same purpose as the decoct ion of chamomile, that of serving as a vehicle for fomentations and enemas ; and the same observation applies to it. Decoctum papaveius. Decoction of Poppy. Pharm. Lond. " Take of the Capsules of the White Poppy cut, four ounces ; Water, four pints. Boil for a quarter of an hour, and strain." The decoction of the capsules of the poppy'has been frequently used as an anodyne fomentation, and is now, with propriety, introduced as an officinal preparation. Decoctum quercus Decoction of Oak Bark. Ph. Lond. " Take of Oak Bark, one ounce; Water, two pints. Boil down to a pint, and strain." The astringency of the oak bark is extracted by boiling in water; and the decoction is the common form under which it is used, being applied externally in haemorrhoids, prolapsus ani, leucorrhcea, and profuse menorrhagia. Decoctum sarsaparill;e compositum. Compound Decoction of Sarsaparilla. Ph. Lond. Dub. " Take of the Simple Decoction of Sarsaparilla boiling, four pints; Sassafras Wood cut, Raspings of Guaiac Wood, Liquorice Root bruised, of each one ounce; Mezereon, three drachms. Boil for a quarter of an hour." In the formula of the Dublin Pharmacopoeia, the proportion of the mezereon, the active ingredient, is only one drachm to three pints of water. This is nearly the same composition as the Lisbon Diet Drink, celebrated, as has been already remarked, in the treatment of secondary venereal affections, or DECOCTIONS. 47 symptoms appearing during a protracted mercurial course. The efficacy of the preparation has been supposed to depend principally on the mezereon, yet the other substances may add something to its power, and it is perhaps preferable to adhere to the original composition of remedies of this kind, so far as this is unexceptionable. Its dose is four or six ounces, three or four times a-day. Decoctum ulmi. Decoction of Elm. Ph. Lond. Dub. " Take of the Fresh Bark of the Elm bruised, four ounces: Water, four pints. Boil down to two pints, and strain." This decoction has been recommended in cutaneous eruptions, but is little used. Its close ounces. Decoctum veratri. Decoction of White Hellebore. Pharm. Lond. " Take of White Hellebore Root beat, an ounce; Water, two pints; Rectified Spirit, two fluid ounces. Boil the white hellebore root with the water, down to a pint, and strain; when cold, add the spirit." This decoction is employed as an external application in some cutaneous diseases, principally in psora. It is a much less unpleasant application than the sulphur ointment, and is occasionally successful. Decoctum digitalis. Decoction of Foxglove. Ph. Dub. " Take of the Leaves of Foxglove dried, one drachm; Water, as much as may be sufficient to afford eight ounces of the strained decoction. Place the vessel on a gentle fire, and remove it when the liquor begins to boil. Digest for a quarter of an hour, and strain." Water extracts sufficiently the active matter of the leaves of foxglove by infusion, and there is therefore no necessity for boiling it upon .them. The decoction in this preparation is, however, so slight, that it cannot SYRUPS. 48 alter the powers of the medicine, and it may be regarded as analogous to the infusion of the other Pharmacopoeias. The proportions too are the same, and it may therefore be given in the same dose. CHAPTER X. SYRUPI.—SYRUPS. Syrups are saturated solutions of sugar in water, in watery infusions, or in vegetable juices. They are seldom very active medicines; and are more commonly employed to render others agreeable, and in pharmacy to communicate peculiar forms. The proportion of sugar in syrups is generally two parts to one of the fluid ; if it is more than this, the solution is disposed to crystalize; if less, it is liable to ferment, and become acescent. Refined sugar ought always to be employed. It is to be melted in the liquid by a gentle heat, and any impurities which collect on its surface when boiling are to be removed. The syrup ought to be kept in a cool place, to prevent the fermentation, which is favoured by a high temperature. The London College have given the genera] direction of keeping them at a temperature not higher than 55°. Syhupus simplex sive communis. Simple or Common Syrup. " Take of Refined Sugar beat to powder, fifteen parts; Water, eight parts. Dissolve the sugar with a gentle heat, and boil a little so as to form a syrup." This solution of sugar is used merely to communicate sweetness of taste, or for the pharmaceutical purposes to which syrups are applied. SYRUPS. 49 Syrupus acidi acetosi. " Take of Acetous Acid (Vinegar,) two pounds and a half; Refined Sugar, three pounds and a half. Boil so as to form a syrup." This acidulous syrup being sufficiently pleasant, may enter into mixtures in which it cannot occasion any chemical decomposition. It is, however, so rarely employed, that being liable to decomposition on keeping, it is not found in the shops. Syrupus althaeas ofpicinalis. Syrup of Althaea. (Syrup. Althaea?, Ph. Lond.) " Take of Fresh Althaea Root cut, one pound; Water, ten pounds ; Refined Sugar, four pounds. Boil the water with the root to one half, and expressing it strongly, strain. Put aside the strained liquor, that the impurities may subside, and to the purified liquor add the sugar; then boil it so as to form a syrup. The water dissolving the mucilage of the Althaea, less than the usual proportion of sugar is required to give it the consistence of a syrup. This mucilage is supposed to give the syrup some demulcent power; this, however, must be very trivial, and it renders it more liable to spontaneous decomposition. Syrupus amomi zingiberis. Syrup of Ginger. (Syrup. Zingib. Ph. Lond. Dub.) "Take of the Root of Ginger beat, three ounces ; Boiling Water, four pounds; Refined Sugar, seven pounds and a half. Macerate the root in the water, in a close vessel, for twenty-four hours; and to the strained liquor, add the beat sugar, so as to make a syrup." This syrup is impregnated with the aromatic flavour and pungency of the ginger, which renders it sufficiently grateful." Vol. II. 8 SYRUPS. 50 Syrupus citri aurantii. Syrup of Orange-Peel. (Syrup. Aurant - Ph. Lond. Dub.) " Take of the Fresh Outer Rind of the Orange, six ounces; Boiling Water, three pounds; Refined Sugar, four pounds. Macerate the rind in water for twelve hours; then to the strained liquor add the sugar beat to powder, and, by the application of a gentle heat, form a syrup." This syrup, like the former, is used on account of its grateful aromatic flavour. The proportion of sugar in it is too small, especially as it is necessary to avoid any dissipation of the water by boiling, to prevent the loss of the flavour of the orange-peel. Syrupus citri medicas, oh'rn Syrupus Limonum. Syrup of Lemon. (Syr. Limon. Ph. Lond. Dub.) " Take of the Juice of Lemons strained, after the impurities have subsided, three parts ; Refined Sugar, five parts ; dissolve the sugar so as to form a syrup." This is a pleasant syrup, used to sweeten and acidulate mixtures, especially those of the mucilaginous kind: there are others, into the composition of which it cannot properly enter, from the chemical agency of the acid. Syrupus colchici autumnalis. Syrup of Colchicum. " Take of the Fresh Root of Colchicum, cut into small pieces, one ounce ; Acetous Acid, sixteen ounces ; Refined Sugar, twenty-six ounces. Macerate the root in the acid for two days, shaking the vessel occasionally ; then expressing it gently, strain it; to the strained liquor add the sugar in powder, and boil a little, so as to form a syrup." Colchicum has been used under this form as a diuretic in dropsy, the dose being from half an ounce to an ounce. The root itself being little employed in modern practice, this syrup is scarcely ever prescribed. SYRUPS. 51 Syrupus dianthi caryophilui. Syrup of Clove July-Flower. (Syr. Caryoph. R. Ph. Dub.) " Take of the Fresh Petals of the Clove July-Flower freed from the heels, one pound ; of Boiling Water, four pounds ; of Refined Sugar, seven pounds. Macerate the petals in the water for twelve hours; then to the strained liquor add the sugar in powder; which dissolve with a gentle heat, so as to form a syrup. This syrup derives from the flowers a rich red colour, and an agreeable flavour, and from these qualities is frequently used in mixtures. Syrupus papaveris somniferi. Syrup of White Poppy. (Syr. Papav. Ph. Lond. Dub.) " Take of the Dried Capsules of the White Poppy, freed from the seeds, two pounds; Boiling Water, thirty pounds; Refined Sugar, four pounds. Macerate the capsules cut, in the water for twelve hours ; then boil until a third part only of the liquor remain ; and pressing it strongly, strain ; boil down the strained liquor to one half, and again strain ; lastly, the sugar being added, boil a little so as to form a syrup." The active matter of the capsule of the poppy is extracted by water by decoction, and by boiling down the liquor, as directed in this formula, and in those of the other Pharmacopoeias, is obtained in a more concentrated state, whether with any diminution of its powers from the continued decoction, has not been ascertained. The syrup has a considerable narcotic power; and the taste being agreeable, and the dose easily regulated, it is convenient for exhibition to children, a drachm being given to a child a year old. From the supposition that it is uncertain in strength, it has been proposed to substitute for it a composition of simple syrup and tincture of opium; but it is not certain if the operation of this is exactly the same, and there is some risk, that from spontaneous decomposition, part of the active matter of the opium may be precipitated. SYRUPS. 52 Syrupus rhamwi cathartici Syrup of Buckthorn. (Syrup. Rhamn. Ph. Lond.) " Take of the Clarified Juice of ripe Buckthorn Berries, two parts; Refined Sugar, one part. Boil, so as to form a syrup." The juice of the buckthorn is best preserved by being made into a syrup, and it is under this form that it has been used as a cathartic, the dose to an adult being an ounce, or an ounce and a half. Its operation, however, is unpleasant, and the preparation has nothing to recommend it. In the composition of the London Pharmacopoeia, ginger and Jamaica pepper are added, which will communicate a pleasant flavour, and may obviate the griping it is liable to produce. Syrupus rosal centjfolias. Syrup of Damask or Pale Rose. (Syrup. Rosae, Ph. Lond.) "Take of the Fresh Petals of the Damask Rose, one pound; Boiling Water, four pounds; Refined Sugar, three pounds. Macerate the petals in water for twelve hours; then to the strained liquor add the sugar, and boil, so as to form a syrup." The agreeable flavour of the rose is entirely lost in this syrup ; but it has a very weak purgative power, and is sometimes from this quality given to infants in a dose of two or three tea-spoonfuls. Syrupus RosiE gallick. Sj'rup of Red Rose. " Take of the Dried Petals of the Red Rose, seven ounces; Boiling water, five pounds; Refined Sugar, six pounds. Macerate the petals in water for twelve hours ; then boil them a little, and strain: to the strained liquor add the sugar, and again boil, so as to form a syrup." Water, by infusion, extracts the slight astringency and the colour of the rose ; the astringency has been supposed to be at least such as to counteract the laxative quality of the sugar, and it is usually this syrup that enters into the composition of astringent mixtures. SYRUPS. 53 Syrupus scillje Maritime. Syrup of Squill. u Take of the Vinegar of Squill, two pounds; Refined Sugar, three pounds and a half. Dissolve the sugar with a gentle heat, so as to form a syrup." This is a syrup of considerable power, the active matter of squill being dissolved by vinegar, and being little injured in forming it into a syrup. It is the form under which squill is usually given as an expectorant, in a dose of one or two drachms, and it is often added to combinations of expectorant remedies. It is also given to children as an emetic, especially in pertussis, the operation of it being sometimes promoted by the addition of a little ipecacuan or antimonial wine. Syrupus toluiferjE balsami, vulgo Syrupus Balsamicus. Syrup of Tolu Balsam. (Syrup. Tolut. Ph. Lond.) " Take of Common Syrup, two pounds; Tincture of Tolu Balsam, one ounce. With the syrup newly prepared, and removed from the fire, when it has nearly cooled, mix the tincture gradually with agitation." This is an economical mode of preparing this syrup: but the old method, still retained in the London Pharmacopoeia, of boiling Balsam of Tolu in water in a close vessel, and afterwards forming the liquor into a syrup by the addition of sugar, affords a more grateful composition, the syrup being impregnated with the odour of the balsam, without its resinous matter being diffused through it, which, as prepared by the formula of the Edinburgh College, renders it white and turbid. The syrup is used merely on account of its flavour, and to many this is rather disagreeable. On the supposition of tolu balsam being an expectorant, it sometimes enters into the composition of mixtures used in catarrh. Syrupus violas odorata3. Syrup of Violet. (Syrup. Viola?, Ph. Dub.) " Take of the fresh flowers of the Sweet-scented Violet, one pound; Boiling Water, four pounds; Refined Sugar, seven pounds and a half. Macerate the SYRUPS. 54 (lowers in water for twenty-four hours in a covered glass or earthen vessel. Then strain, without expression, and to the strained liquor add the beat sugar, so as to form a syrup." This syrup has a fine blue colour, which is, however, lost on keeping. It is a very gentle laxative, and as such is given to infants in a dose of one or two tea-spoonfuls. It remains to notice those few syrups which have exclusively a place in the London or Dublin Pharmacopoeias. Syrupus croci. Syrup of Saffron. Ph. Lond. " Take of Saffron, an ounce; Boiling Water, a pint. Macerate the saffron in the water for twelve hours, in a vessel lightly closed; then strain the liquor, and add the sugar to it." This syrup is employed in mixtures merely on account of its colour. Syrupus mori. Syrup of Mulberry. Ph. Lond. " Take of Mulberry Juice strained, a pint; Refined Sugar, two pounds. Dissolve the sugar in the juice in the manner directed with regard to syrup." The syrups of several acidulous fruits had formerly a place in the London Pharmacopoeia. This is retained as one of the most grateful. Syrupus Rhoeados. Syrup of Red. Poppy. Ph. Lond. (Syr. Papav. Errat. Ph. Dub.) " Take of the Recent Petals of the Red Poppy, one pound; Boiling Water, a pint and two fluid ounces; Refined Sugar, two pounds and a half. To the water heated by a water-bath, add the petals of the red poppy gradually, stirring them occasionally, then having removed the vessel, macerate for twelve hours; press out the liquor, and put it aside, that the impurities may SYRUPS. 55 subside; lastly, add the sugar in the manner directed with regard to common syrup." This syrup is valued only on account of the fine red colour which it receives from the petals of the flower. Syrupus senna;. Syrup of Senna. Ph. Lond. Dub. " Take of Senna Leaves, one ounce; Bruised Fennel Seeds, one drachm ; Manna, Refined Sugar, of each one pound; Boiling Water, one pint. Macerate the senna leaves and the fennel seeds in water for twelve hours. Strain the liquor, and mix with this the manna and sugar." The directions in the Dublin Pharmacopoeia are similar, except that the proportion of senna is only half an ounce, and the fennel seeds are omitted. This is designed as a purgative syrup for children, and will answer this purpose perfectly well; though the infusion of senna, sweetened with sugar, which is in common use, being of extemporaneous preparation, is perhaps preferable. Syrupus allii. Syrup of Garlic. Ph. Lond. " Take of the Roots of Garlic, cut, one pound; of Boiling Water, two pounds. Macerate the garlic in the water for twelve hours in a covered vessel, and form a syrup, by adding sugar to the strained liquor." Garlic has been employed as an expectorant in some forms of catarrh and dyspnoea, under the form of syrup. It has perhaps, however, no such power as to entitle it to a place as an officinal preparation. Syrupus opii. Syrup of Opium. Ph. Lond. " Take of the Watery Extract of Opium, eighteen grains; Boiling Water, eight ounces. Macerate them together until the opium be dissolved; then add sugar so as to form a syrup." This is designed as a substitute for the syrup of poppy; and as the watery extract of opium, not the opium in substance, is dissolved, it may not be liable to the objection of any portion being precipitated from SYRUPS. 56 decomposition. It is not altogether certain, however, whether, in the preparation of the watery extract, (to be afterwards noticed,) the narcotic power of the opium is not impaired, and, therefore, whether this preparation from it will be always of uniform strength. An ounce of the syrup contains about one grain of the watery extract; its strength, therefore, will be similar to the medium strength of the syrup of poppy. MELLITA.—MEDICATED HONEYS. Honey has been employed instead of saccharine matter in some pharmaceutical preparations. Combined with vinegar, either alone or with the impregnation of the active matter of vegetables, the kind of composition named Oxymel is formed. Combined merely with infusions of vegetable substances, it forms what are more exclusively named Medicated Honeys. As these preparations have no particular advantage over syrups, and as honey, from idiosyncrasy, produces unpleasant effects on some individuals, they have been rejected by the Edinburgh College. A few, however, retain a place in the London and Dublin Pharmacopoeias. Mhl. despumatum. Clarified Honey. Ph. Lond. " Liquefy honey in a water-bath, then remove the scum." Honey, as it is expressed from the comb, is liable to contain wax and other impurities. When the honey is liquefied, these, in a great measure, separate and rise to the surface, so as to be easily removed. The honey thus purified is ordered in the other preparations into which honey enters. Mel. boracis. Honey of Borax. Ph. Lond. 11 Take of Borax in powder, a drachm; Clarified Honey, an ounce. Mix them. SYRUPS. 57 In this composition, honey is useful, as giving the proper consistence. It is designed as an application in aphthous affec ions of the tongue and fauces, the borax giving a sense of coolness, and removing the foul crust. Mel Rosas. Honey of Rose. Ph. Lond. Dub. " Take of the Dried Petals of the Red Rose, four ounces ; Boiling Water, three pints ; Clarified Honey, five pints. Macerate the petals in the water for six hours, then to the strained liquor add the honey, and boil it down in a water-bath to the proper consistence." This preparation is similar to the syrup of the red rose, and may be applied to the same purposes. Oxymel. Oxymel. Ph. Lond. Dub. " Take of Purified Honey, two pounds ; Acetic Acid (Distilled vinegar) one pound. Boil them in a glass vessel, on a slow fire, to the proper consistence." This has long been in use as a remedy in catarrhal affections, and is also the basis of a cooling detergent gargle Oxymel scill.e. Oxymel of Squill. Ph. Lond. Dub. " Take of Clarified Honey, three pounds ; Vinegar of Squill, two pounds. Boil in a glass vessel, over a slow fire, to a proper consistence." Under this form squill has been employed, principally as an expectorant. Its dose is one or two drachms. Oxymel colchici. Oxymel of Colchicum. Ph. Dub. " Take of the Fresh Root of Colchicum cut into thin slices, one ounce ; Distilled Vinegar, one pint; Clarified Honey, two pounds. Macerate the colchicum with the vinegar for two days, in a glass vessel; then strain the liquor pressed out strongly from the root, and add the honey. Lastly, boil the mixture, stirring it frequently with a wooden spoon, to the consistence of a syrup," This is essentiallv the same with the svrup of colchi- Vol II. 9 WINES 58 cum already noticed ; nor can it derive any advantage from honey being used in its preparation. Oxymel jeruginis. Oxymel of Verdigrease. Ph. Dub. (Liniment Ph. Lond.) " Take of Prepared Verdigrease, one ounce ; Vinegar, seven ounces ; Clarified Honey, fourteen ounces. Dissolve the verdigrease in the vinegar, and strain it through linen, then add the honey, and boil the mixture to a proper thickness." Under this form, verdigrease has been applied as a stimulant and escharotic to foul ulcers. CHAPTER XI. VINA—WINES. Wine is capable, by infusion, of extracting several of the proximate principles of vegetable substances. From the portion of alcohol it contains, it dissolves in some measure their resin, extract and essential oil; its watery part dissolves their gum or mucilage ; and being milde* and more pleasant to the taste than diluted alcohol, it is sometimes preferred to it as a solvent; hence Medicated Wines have long been in use, and some of them are still retained in the Pharmacopoeias. It cannot be said however, to be well adapted to this use. Wine itself, when not carefully excluded from the air, is apt to decompose and become acescent; and, when it holds vegetable matter in solution, it appears to be still more liable to suffer this change. This has been established by the researches of Parmentier; and the greater number of medicated wines, if kept for any length of time, become medicated vinegars. Now this change may modify the powers of the dissolved matter ; and in some cases, where the wine is taken in a consi- derable dose, must prove hurtful to the stomach, espe- WINES. 59 cially in dyspeptic affections. Accordingly, few of the medicated wines are now employed. The spontaneous decomposition to which these wines are liable, is sometimes attempted to be obviated by the addition of a portion of alcohol, but this is attended only with imperfect success. From the tartaric acid which some wines contain, they are capable of acting chemically on some of the metals, and are better solvents of some metallic preparations than water or alcohol. Vinum aloes socotorinas, vulgo Tinctura Sacra. Wine of Soco« torine Aloes. Sacred Tincture. (Vinum Aloes, Ph. Lond. Dub.)' "Take of Socotorine Aloes, reduced to powder, one ounce; Lesser Cardamom Seeds, Ginger Root, of each bruised, one drachm ; Spanish White-Wine, two pounds. Digest for seven days, shaking frequently, and strain." In the Dublin and London Pharmacopoeias, the proportion is an ounce of aloes to a pound of the medicated wine; and the solvent is not pure wine, but wine with the addition of a third part of diluted alcohol. Aloes is entirely soluble in wine ; so that in this preparation all its virtues are obtained, and from the presence of the resinous matter of the aloes, it is not liable to decomposition. It is a stimulating cathartic, which has long been in use under the name of Sacred Tincture. It produces its full effect in the dose of one ounce. In a dose of one or two drachms, it is given to excite the action of the intestines and neighbouring organs, in dyspepsia, amenorrhcea and similar affections. Vinum gentian.*: compositum vulgo Vinum Amarum. Compound Gentian Wine. " Take of Gentian Root, half an ounce ; Peruvian Bark, one ounce; Orange-Peel dried, two drachms ; Canella bark, one drachm ; Diluted Alcohol, four ounces; Spanish White-Wine, two pounds and a half. On the root and barks cut and bruised, pour first the diluted aleohol ; and after twenty four hours, add the wine. Then macerate for seven days, and strain." WINES. 60 This wine is designed as a stomachic ; and has been regarded a>> preferable to the tincture of similar composition, as being more mild and grateful, and therefore better for continued use; but from its tendency to become acescent, it is not well adapted to administration in dyspepsia. Its dose is six drachms. Vinum ipecacuanhas. Ipecacuan Wine. (Vinum Ipecacuanhaea, th. Lond. Dub.) " Take of Ipecacuan Root bruised, one ounce ; Spanish White-Wine, fifteen ounces. Macerate for seven days, and strain through paper." Wine extracts sufficiently the active matter of ipecacuan, and covers its taste and flavour, while it is less pungent than diluted alcohol. This wine is often used as an emetic, especially to children. Its dose is one ounce to an adult, one drachm to a child a year old. Vinum nicotiana: tabaci. Tobacco Wine. " Take of the leaves of Tobacco, one ounce ; Spanish White Wine, one pound. Macerate for seven days, and strain through paper." Under this form, Tobacco has been used as a diuretic in dropsy. The Dose is thirty drops, gradually increased to sixty or eighty twice a day. it is liable, however, to excite sickness in this large dose, and in a smaller dose often fails in its diuretic effect. Vinum rhei palmati. Rhubarb Wine. " Take of the Root of Rhubarb cut, two ounces ; Canella Bark bruised, one drachm ; Diluted Alcohol, two ounces ; Spanish White-Wine, fifteen ounces. Macerate for seven days and strain through paper." Wine extracts the active matter of rhubarb, and this medicated wine operates as a purgative, in a dose from half an ounce to an ounce. The tincture is in general to be preferred to it, as more uniform, and not liable to decomposition. WINES. 61 Vinum opii. Wine of Opium. Ph. Lond. "Take of Extract of Opium, an ounce ; Cinnamon Bark bruised, Cloves bruised, each, one drachm ; Wine a pint. Macerate for eight days, and strain." Wine appears to dissolve sufficiently the active matter of opium, and has often been used as a menstruum. With the addition of aromatics, it formed the liquid laudanum of Sydenham, and was at one time an officinal preparation in the Pharmacopoeias, though afterwards excluded, to give place to the simple tincture of opium. It is now restored by the London College, as it had still continued in use, and is supposed to have some advantages over the tincture. It is nearly of the same strength. Vinegar impairs the narcotic power of opium, hence if this medicated wine were liable to aeescency, it might be regarded as an uncertain preparation, but it is possible that the resino-extractive matter of the opium and the aromatics may counteract any spontaneous decomposition. Vinum ferri. Wine of Iron. Ph. Dub. " Take of Iron Wire in small pieces, four ounces ; White Rhenish Wine, four pints. Sprinkle the pieces of iron with a little of the wine, and expose then) to the air, until they are covered with rust ; then add the remaining wine : digest for seven days, shaking the vessel occasionally, and lastly strain the wine." The iron being oxidated by the joint action of the wine and the atmospheric air, a portion of the oxide is dissolved by the tartaric acid of the wine. The chalybeate impregnation must, however, be variable, according to the aciditv oi the wine, and it is therefore perhaps [ referable to empioy a preparation of more uniform strength. 62 VINEGARS. CHAPTER XII. ACETA.—VINEGARS. Vinegar is generally capable of dissolving all those proximate principles of vegetables which are soluble in water, and with regard to some substances its acid appears farther to increase its solvent power. But, at the same time, it very often modifies their medicinal qualities, either by the chemical changes it occasions, or more generally, perhaps, by the action it exerts on the stomach. Hence there is only one medicated vinegar of any importance,—the Vinegar of Squill ; the active matter of this root being dissolved by it, and appears to suffer no alteration. The activity of colchicum appears to reside in a similar acrid matter, and it also affords a medicated vinegar; of less importance however, as the colchicum itself is little employed. As a solvent of camphor, the concentrated acetic acid is also used in one preparation. Acetum aromaticum. Aromatic Vinegar. " Take of the dried tops of Rosemary ; the dried leaves of Sage, of each four ounces ; dried Lavender Flowers, two ounces ; Cloves, two drachms ; distilled Acetous Acid, eight pounds. Macerate for seven days, and strain the expressed liquor through paper." This is an improved formula for a preparation which has long had a place in the different Pharmacopoeias, under the name of Acetum Prophylacticum, as an antiseptic and preservative against the operation of contagion. From the impregnation of the vinegar with the flavour of the aromatic vegetables, it is a grateful perfume, but it is weak, and its odour is very soon impaired. VINEGARS. 63 Acidum acetosum camphoratum. Camphorated Acetous Acid. (Acid Aceticum Camph. Ph. Dub.) " Take of the stronger Acetous Acid, six ounces ; Camphor, half an ounce. Rub the camphor with a little alcohol into powder, which put into the acid, that it may be dissolved." Camphor is soluble in the concentrated acetic acid, and the solution has an odour highly fragrant and pungent. It has been used as a stimulating perfume, more grateful thaw the common odoriferous essences. It forms what is named Aromatic Spirit of Vinegar. The preparation of the Pharmacopoeia, however, especially that of the Edinburgh College, is inferior in pungency, owing to a weaker acetic acid being employed. Acetum scillas maratimas. Vinegar of Squill. (Acetum Scillae, Ph. Lond. Dub.) " Take of Squill Root dried, two ounces; distilled Acetous Acid, two pounds and a half; alcohol, three ounces. Macerate the squill with the acetous acid for seven days : express the acid ; to which add the alcohol; and when the impurities have subsided, pour off the liquor." The London College order a pound of squill root, recently dried, to six pints of vinegar, and half a pint of proof spirit,—a proportion of it, either unnecessarily large, or which must afford a preparation much stronger than what has been in common use. Vinegar appears to dissolve completely the active matter of squill, without much impairing its powers : the addition of the alcohol is designed to counteract any spontaneous decomposition to which the vinegar might be liable. Under this form, squill is generally employed as an expectorant, the dose being one drachm : or more usually indeed in the form of the syrup, prepared from this medicated vinegar. TINCTURES. 64 Acetum colchici. Vinegar of Meadow Saffron. Ph. Lond. " Take of the fresh Root of Meadow Saffron cut, one ounce ; Distilled Vinegar, a pint ; Proof Spirit, a fluid ounce. Macerate the root with the vinegar, in a close glass vessel, for twenty-four hours ; then press it out, and put it aside, that the impurities may subside ; lastly, add the spirit to the clear liquor." Colchicum bears a considerable resemblance to squill, and its active matter is so far similar, that it appears to be dissolved by vinegar, without its powers being altered. It has been given as a diuretic, either under this form, or made into an oxymel, by the addition of honey ; but in modern practice it is little employed. CHAPTER XIII. TINCTURE.—TINCTURES. Tinctures are solutions usually of vegetable, sometimes, how r ever, of animal, and even of mineral substances in spiritous liquors. The solvent may be alcohol either pure, diluted with water, or impregnated with ammonia or ether. Alcohol dissolves the resin, camphor, and essential oil of plants ; it is more particularly employed as the menstruum for substances purely resinous, or whose virtues reside in a resin. Where a portion of gum is mingled with the resin, or where tannin or extractive matter is the active principle, diluted alcohol is the proper solvent: it in general dissolves the active matter of all entire vegetable substances, as the bark, leaves, flowers; and wherever it can be properly applied, it is preferable to pure alcohol, as more economical and less pungent. Alcohol, impregnated with ammonia, is employed only in forming tinctures of a few TINCTURES. 65 substances, with the medicinal operation of which, ammonia is supposed to coincide. Tinctures usually contain the active matter of the substances from which they are prepared, in a more concentrated state than infusions or decoctions, the power of the solvent being greater ; hence they require to be given only in a small dose ; and the power of the solvent, which is otherwise considerable, may be neglected. They have the still more important advantage of not being liable to spontaneous decomposition ; the affinities of the elements of vegetable matter, whence new combinations are established, which are favoured by water, being counteracted by alcohol; and hence a tincture, if kept secluded from the air, so as to prevent the loss of the alcohol by evaporation, can be preserved any length of time without decomposition. Tinctures are prepared by infusing the materials in the spirit, without the application of heat. By applying heat, the solvent power is so far promoted, that the impregnation is effected in a shorter time ; but the inactive and grosser matter, it has been supposed, is frequently liable to be extracted, and the high temperature is unnecessary, as, by allowing the solvent to remain a sufficient time (fourteen days usually j on the ingredients, it is fully saturated. Alkaline salts were at one time supposed to increase the solvent power, both of alcohol and diluted alcohol, the tincture being of a much deeper colour when a small portion had been added. But this arises, in part at least, from the action of the alkali on the colouring matter, as the same effect is obtained when they are added to a tincture alreadj prepared ; and even where they increase the solubility of some principles, as of resinous matter, they do not always coincide in medicinal operation with the substance operated on, and they render the tincture more nauseous. Some tinctures are liable to decomposition on diluting them with water, those especially prepared with pure alcohol, in which resinous matter chiefly is dissolved, the resin being precipitated. Even tinctures prepared with Vol. II. 10 TINCTURES. 66 di'uted alcohol are frequently rendered turbid by dilution with water. And it sometimes happens even that a decomposition ensues on mixing a tincture prepared with alcohol with another prepared with diluted alcohol. Such decompositions require to be attended to in their administration, and to be so far obviated, at least when the precipitation is copious, as that by trituration with mucilage the resinous matter shall be diffused. Txnc tura aloes socoTOMNiE Tincture of Aloes. (Tinct. Aloes, Ph. Load. Dub.) " Take of Socotorine Aloes in powder, half an ounce; Extract of Liquorice, one ounce and a half; Alcohol, four ounces ; Water, one pound. Digest for seven davs with a gentle heat in a close vessel, shaking the vessel frequently, and pour off the tincture w hen clear." This tincture which has a place in all the Pharmacopoeias, is the only one in which the solvent has a still larger proportion of water than the diluted alcohol of the usual strength. It dissolves, however, the aloes sufficiently. The liquorice is designed to cover the taste, which it does very imperfectly. The tincture may be employed as a cathartic in the dose of an ounce, but is seldom used ; aloes, from its intense bitterness, being better prescribed under the form of pill. Tinctura aloes .KTHEREA F.thereal Tincture of Aloes. " Take of Socotorine Aloes, Myrrh, of each in powder, one ounce and a half; English Saffron, one ounce ; Spirit of Sulphuric Ether, one pound. Digest the myrrh with the spirit for four days in a closed phial ; then add the saffron and aloes. Digest again for four days ; and when the impurities have subsided, pour off the tincture." If the ingredients of this tincture were digested together, the spirit would be so much saturated with the aloes as to take up little of the my rrh ; but by digesting it first on the myrrh, it dissolves a larger quantity of it, and is still capable of dissolving a sufficient proportion of the TINCTURES. 67 aloes and saffron. The spirit of sulphuric ether affords a more grateful tincture than alcohol. A similar preparation has long kept its place in the Pharmacopoeias, under the name of Elixir Proprietaris, and has been much used as a stimulant aperient in dyspeptic affections, jaundice and amenorrhoea, given in a dose of one or two drachms. In the dose of six drachms it acts as a cathartic Tinctura aloes cum myrrah. Tincture of Aloes and Myrrh. (Tinct. Aloes Comp- Ph. Lond. et Dub.) " Take of Myrrh in powder, two ounces ; Alcohol, one pound and a half; Water, half a pound. Mix the alcohol with the water ; then add the my rrh ; digest for fourdays ; and lastly , add, of Socotorine Aloes, one ounce and a half; English Saffron, one ounce. Digest again for three days, and pour off the pure tincture." This tincture differs in little from the former, but in the menstruum. Being less grateful, it is used principally externally as an application to bleeding wounds, and a stimulant to foul ulcers. Tinctura amomi repentis. Tincture of Cardamom. (Tinct. Cardam. Ph. Lond. et Dub.) " Take of Cardamon Seeds, four ounces; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." This tincture is used for its aromatic flavour and pungency ; and as these are not considerable, it is but little employed. Tinctura aristolochle serpentarije. Tincture of Snake-Root. (Tinct. Serpent Ph. Lond. et Dub ) " Take of Virginian Snake-Root bruised, two ounces ; Cochineal in powder, one drachm ; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." Serpentaria is seldom exhibited under the form of tincture, and it would require indeed to be given in such a dose, that the power of the menstruum would be pre- TINCTURES. 68 dominant. As a grateful bitter, it may be given occasionally in dyspepsia in a dose of two drachms. Tinctura benzoin composita, vulgo Balsamum Traumaticum. Compound Tincture of Benzoin. (Tinct. Benzoini Comp. Ph. Lond. Dub.) <4 Take of Benzoin in powder, three ounces ; Balsam of Peru, two ounces ; Hepatic Aloes, half an ounce ; Alcohol* two pounds. Digest for seven days, and strain through paper." Balsam of Tolu and Storax are substituted in the other Pharmacopoeias for the Peru Balsam. Ttiis is used only externally, and principally as an application to recent superficial wounds. It. has long been in use under the names of Wade's Balsam and Friar's Balsam. A piece of linen moistened with it generally stops the haemorrhage from a slight wound, and allows it to heal by the first intention. It is also sometimes applied as a stimulant to foul ulcers. Tinctura camphors, vulgo Spiritus Vinosus Camphoratus. Tincture of Camphor. (Spirit. Camphor. Ph. Lond. Dub.) " Take of Camphor, one ounce ; Alcohol, one pound. Mix, so as to dissolve the camphor. It may be also made with a double or triple proportion of camphor." In the London and Dublin Pharmacopoeias, it is prepared of the strength of two ounces to a pint of spirit. This solution is used externally as a stimulant and anodyne application in chronic rheumatism and spasmodic pains, being rubbed on the part. It is applied in a similar manner to bruises and strains. Linen moistened with it is used as an application to chilblains ; and it is sometimes added in small quantity to collyria employed in ophthalmia. The London College have inserted another solution of camphor in alcohol, impregnated with ammonia, under the name of LlNIMENTUM CAMPHOR55 COMPOSITUM. " Take of Camphor, two ounces ; Water of Ammonia, six ounces; Spirit of Lavender, a pint. Mix the water of TINCTURES. 69 ammonia with the spirit, and distil a pint from a glass retort with a gentle heat. Dissolve the camphor in the distilled liquor." This liniment is applied te the same uses as the preceding, but the addition of the ammonia renders it more powerful as a stimulant. Tinctura castorei. Tincture of Castor. (Tinct. Castor. Ph. Lond. Dub.) " Take of Russian Castor, one ounce and a half; Alcohol, one pound. Digest for seven days, and strain through paper." In the Dublin Pharmacopoeia, this tincture is ordered to be prepared with diluted alcohol; but with pure alcohol it is more grateful. Castor is a substance nearly inert, and this tincture, in which a small quantity of it only is dissolved, can scarcely be supposed to have any medicinal efficacy. It is given sometimes as an antispasmodic, in a dose of from half a drachm to a drachm. Tinctura castorei composita. Compound Tincture of Castor. " Take of Russian Castor, one ounce ; Assafoetida, half an ounce; Ammoniated Alcohol, one pound. Digest for seven days, and strain through paper." This tincture, which has a place only in the Edinburgh Pharmacopoeia, is rather more active than the former, from the addition of the assafoetida and the ammonia. It is given in hysteria in the dose of a drachm. Tinctura ciNCHONiE officinalis. Tincture of Peruvian Bark. (Tinct. Cinchona, Ph. Lond. Dub.) " Take of Peruvian Bark in powder, four ounces; Diluted Alcohol, two pounds and half. Digest for seven days, and strain through paper." In the formula of the London College, seven ounces of bark are ordered to two pints of proof spirit, whether with the effect of rendering the tincture much stronger may be considered as doubtful. The active matter of bark is extracted by diluted alco- 70 TINCTURES. hoi, but so sparingly, that it may be doubted whether in the tincture the powers of the menstruum are not greater than those of the bark. It can therefore never be employed where large quantities of cinchona are required. It is used only as a bitter in dyspepsia, occasionally, in a dose of two drachms, and for this purpose the compound tincture of bark, to be afterwards noticed, is preferable. Tinctura cinnamoni composita olim Tinctura Hromatica. Com- pound Tincture of Cinnamon, formerly Aromatic Tincture. (Tinct. Ciunam Comp Ph. Lond. Dub.) " Take of Cinnamon Bark bruised, Cardamon Seeds bruised, each one ounce; Long Pepper in powder, t.vo drachms ; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain." This is a grateful aromatic tincture, seldom used by itself, but frequently added to other tinctures, or to mixtures, to communicate flavour and pungency. It is thus often used in combination with bitters and astringents. Tinctura coloiMba:. Tincture of Colombo. (Tinct. Colomb. Ph. Lond. Dub.) "Take of the Root of Colombo in powder, two ounces; Diluted Alcohol, two pounds. Digest for seven days, and strain through paper." Colombo does not appear to yield its active matter very readily, at least this tincture is not strong, and cannot be employed for any of the more important purposes for which this root is prescribed. It is used indeed merely as a bitter tincture in dyspepsia, in a dose of three or four drachms. Tinctura convolvuli jalapas. Tincture of Jalap. (Tinct. Jalap. Ph. Lond. Dub ) " Take of the Root of Jalap in powder, three ounces ; Diluted Alcohol, fifteen ounces. Digest for seven days, and strain through paper." The activity of jalap resides in a resinous matter, which in this tincture is extracted along with a portion of mucilage. It may be given as a cathartic, in a dose of TINCTURES. 71 lour or six drachms. Jalap, however, is usually rather given in substance, and scarcely ever under this form. Tinctura croci. Tincture of Saffron. (Tinct. Croci, Ph. Dub.) " Take of English Saffron, one ounce; Diluted Alcohol, fifteen ounces. Digest for seven days, and strain through paper." This tincture is to be valued only for its colour. T;nctura digitalis purpurea!. Tincture of Foxglove. (Tinct. Digital. Ph. Lond. Dub.) " Take of the dried Leaves of Foxglove, one ounce ; Diluted Alcohol, eight ounces. Digest for seven days, and strain through paper." In the preparation of this very active and important tincture, the same proportions are ordered in all the Pharmacopoeias. Tincture of Foxglove has been supposed to be the form under which the operation of this plant as a narcotic is best obtained, and it is with this view that it has been introduced: it has also the important advantages, that it can be kept without the powers of the digitalis being impaired, and that its close is easily regulated. The usual dose is ten drops, which, according to the general rules observed in the administration of digitalis, is to be continued until its effects are obtained. Tinctura ferula; assafoetida;. Tincture of Assafoetida. (Tinct. Assafoetid. Ph. Lond. Dub.) " Take of Assafoetida, four ounces; Alcohol, two pounds and a half. Digest for seven days, and strain through paper." Alcohol being the solvent in this tincture, it is a solution chiefly of the resinous part of the assafcetida, and it is more grateful than when made with proof spirit. The Dublin College order a menstruum, composed of two pints of rectified spirit, and eight ounces of water. As a remedy in tympanitis and hysteria, it is sometimes given in a dose of one drachm ; but in any quantity in which it can be given, so thar the operation of the solvent shall not be predominant, its eiiects must be extremely trivial, TINCTURES. 72 Tinctura gentians composita, vulgo Elixir Stomachicum. Compound Tincture of Gentian. (Tinct. Gentian. Comp. Ph. Lond. Dub.) " Take of Gentian Root, two ounces; dried Orange Feel, one once; Canella Bark, half an ounce; Cochineal, half a drachm; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." In this tincture, the bitterness of the gentian is completely extracted, and it is rendered more grateful by the aromatic quality of the orange peel and canella. It is used as a stomachic in a dose of two or three drachms, in cases where the stomach is disordered from any occasional cause. In more permanent forms of dyspepsia, it cannot be employed with equal advantage, and the continued use of tinctures of this kind ought always, as Cullen remarked, to be avoided, as being liable to accustom the stomach to the stimulus of ardent spirit. Tinctura guajaci. Tincture of Guaiac. (Tinct. Guaiac, Ph. Lond. Dub.) " Take of the Resin of Guaiac, one pound; Alcohol, two pounds and a half. Digest for seven days and strain through paper." The proportion of guaiac to the solvent of this tincture, is unnecessarily large. Only half a pound in the London Pharmacopoeia, and four ounces in the Dublin Pharmacopoeia, are ordered to two pints of alcohol. This tincture may be given in a dose of two or three drachms, but it is inferior in activity to the one which follows. Tinctura guajaci ammoniata. Ammoniated Tincture of Guaiac. (Tinct. Guaiac. Amm. Ph. Lond. Dub.) " Take of the Resin of Guaiac, four ounces; Ammoniated Alcohol, one pound and a half. Digest for seven days, and strain through paper." As the ammonia coincides with the guaiac as a stimulant and diaphoretic, this affords a preparation of more efficacy, it is supposed, than the simple tincture, and it TINCTURES. 73 is more frequently employed. It is given in chronic rheumatism, in a dose of from one to two drachms. Tinctura hf.llebori nigri. Tincture of Black Hellebore. (Tinct. Helleb. Nig. Ph. Lond. Dub.) " Take of black Hellebore Root bruised, four ounces; Cochineal, half a drachm; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." It was under the form of this tincture that black hellebore was celebrated by Mead as an emmenagogue, in a dose of one drachm. Cullen remarks with regard to it, that he had never found it successful, and it is now little used. Tinctura hyoscyami nigri. Tincture of Black Henbane. (Tinct. Hyoscyam. Ph. Lond. Dub.) " Take of the Dried Leaves of Black Henbane, one ounce; Diluted Alcohol, eight ounces. Digest for seven, days, and strain through paper." Henbane has been introduced in modern practice as a substitute for opium in particular cases, already pointed out under its history. The inspissated juice being liable to be variable in strength, the tincture has been employed, and has now a place in all the Pharmacopoeias, nearly of the same strength. Its dose has been stated to be twentyfive drops, but in general not much effect is obtained from it under a dose of half a drachm. Tinctura kino. Tincture of Kino. (Tinct. Kino, Ph. Lond. Dub.) "Take of Kino, two ounces; Diluted Alcohol, one pound and a half." Kino consists principally of tannin ; it is entirely soluble in diluted alcohol. The dose of this tincture is from half a drachm to a drachm. Vol. II. 11 TINCTURES. 74 Tinctura lauri cinnamomi. Tincture of Cinnamon. (Tinct. Cinnamom, Ph. Lond. Dub.) " Take of Cinnamon Bark bruised, three ounces ; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." The diluted alcohol is impregnated with the aromatic flav our of the cinnamon, and it is merely as possessing this flavour that this tincture is used in mixtures. Tinctura meloes vesicatorii, vulgo Tinctura Cantharidum. Tincture of Cantharides. (Tinct. Cantharid. Ph. Dub. —Tinct. Lyttae, Ph. Lond.) " Take of Cantharides bruised, one drachm; Diluted Alcohol, one pound. Digest for seven days, and strain through paper." Diluted alcohol extracts and holds dissolved the acrid matter of cantharides, and it is under this form that this substance has been generally employed internally, being more manageable in its dose than it is in powder. It has been given as a diuretic in dropsy, and as a remedy in incontinence of urine, gleet, leucorrhcea, and some cutaneous diseases. Its dose is from ten to twenty drops, increased gradually until some sensible operation is produced. Dr. C. Smith has remarked, however, that in ischuria arising from debility of the coats of the bladder, he had found little advantage derived from the tincture, while in substance the cantharides had been successful. The tincture is also employed externally as a rubefacient. Tinctura mimosas catechu, olitn Tinctura Japonica. Tincture of Catechu. (Tinct. Catechu, Ph. Lond. Dub.) " Take of Catechu, three ounces; Bark of Cinnamon, two ounces; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." Catechu, consisting almost entirely of tannin and extractive matter is dissolved by diluted alcohol, and in this tincture it is rendered more grateful by the cinnamon. It is given in a dose of one drachm, as an astringent. TINCTURES. 75 Tinctura myrrhas. Tincture of Myrrh. (Tinct. Myrrhae, Ph. Lond. Dub.) " Take of Myrrh in powder, three ounces; Alcohol, twenty ounces; Water, ten ounces. Digest for ten days, and strain through paper." Myrrh being principally resinous, is not entirely soluble in common proof spirit, and therefore alcohol less diluted is employed for its solution. The tincture is used principally as an external stimulant and antiseptic application, more especially in affections of the teeth and gums. Tinctura opii, sive Thebaica ; vulgo, Laudanum liquidum. Tincture of Opium. (Tinct. Opii, Ph. Lond. Dub.) " Take of Opium, two ounces; Diluted Alcohol, two pounds. Digest for seven days, and strain through paper." In this tincture all the active matter of opium is dissolved, the residuum being impurities or insoluble matter, and a given quantity of the tincture having been found to produce the same effects on the system nearly as the quantity of opium, which, by calculation, it contained, ought to have done, allowance being made for the undissolved matter. The proportion of opium to each drachm of the tincture is five grains, but by evaporation it is found to yield only three grains and a half; twentyfive drops is supposed to be equal in power to one grain of solid opium, and is the dose commonly given to a person not accustomed to it. It is of the same strengt h as ordered in the different Pharmacopoeias. Laudanum, as this tincture is named, is given in all the cases in which opium is usually administered, and is preferred to it as being more speedy in its operation, more manageable in its dose, and more convenient for combination with other remedies. Where the stomach is in an irritable state, so as to be easily excited to vomiting, or where the operation of the opium is wished to be exerted more slowly, or more peculiarly on the intestinal canal as in diarrhoea and spasmodic colic, it is given in 76 TINCTURES. the solid state, and usually in the form of pill. Externally the tincture is occasionally applied locally as a stimulant and anodyne. Tinctura opii ammoniata ; olim, Elixir Paregoricum. Ammoniated Tincture of Opium. " Take of Benzoic Acid, English Saffron, of each three drachms; Opium, two drachms; Volatile Oil of Anise, hall a drachm; Ammoniated Alcohol, sixteen ounces. Digest for seven days in a shut phial, and strain through paper." This formula is designed as the improvement of a preparation which has long been medicinally employed under the name of Paregoric Elixir, and which, as a weak and pleasant opiate, has in particular been much used as a remedy in catarrh. The formula, however, is but ill contrived. While the ammonia can add nothing to the efficacy of the preparation, its pungency renders it extremely ungrateful; and the tincture approaches too nearly in Strength to the common tincture of opium. The Paregoric Elixir of the London Pharmacopoeia, and which has now also a place in the Dublin Pharmacopoeia, (Tinct. Opii Camphorata, to be afterwards noticed,) is better adapted to the purposes for which it is designed, and is generally preferred. The composition of the Edinburgh College contains a grain of opium in a drachm, and this is its medium dose. The other does not contain more than a grain in half an ounce. The operation of the opium cannot be much influenced by the substances with which it is combined in this formula. The common application of it is as a remedy in catarrhal affections. Its dose is from half a drachm to a drachm, sometimes two drachms, taken generally at bedtime. Tinctura rhei palmati. Tincture of Rhubarb. (Tinct. Rhei, Ph Lond. Dub.) " Take of the Root of Rhubarb, three ounces ; Lesser Cardamom Seeds, half an ounce; Diluted Alcohol, two TINCTURES. 77 pounds and a half. Digest for seven days, ana" strain through paper." Proof spirit extracts nearly all the active matter of rhubarb, and this tincture therefore has all its powers. It is sometimes prescribed in dyspeptic affections and in diarrhoea, in a dose from half an ounce to an ounce. The tincture of the Dublin Pharmacopoeia has the addition of a little liquorice and saffron. Tinctura rhki et aloes ; olim, Elixir Sacrum. Tincture of Rhubarb with Aloes. " Take of the Root of Rhubarb cut, ten drachms ; Socotorine Aloes, six drachms in powder; Lesser Cardamom Seeds bruised, half an ounce ; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." The cathartic power of the rhubarb is in this tincture increased by combination with the aloes. It is employed as a stimulating aperient and purgative, in a dose from half an ounce to an ounce, frequently also as an emmenagogue. Tinctura rhei et gentians ; olim, Tinctura Rhei Amaru. Tinc- ture of Rhubarb with Gentian. " Take of Root of R hubarb, two ounces; Gentian Root, half an ounce; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." This combination of gentian with rhubarb is supposed to render it a more useful remedy in dyspeptic, cases; but the power of the one is so inconsiderable, compared with that of the other, that no important advantage is gained from it. Its dose is from two to four drachms. Tinctura saponis. vulgo L/inimentum Saponaceum. Tincture of Soap. (Liniment. Sapon. Ph. Lond. Dub.) " Take of Soap, four ounces; Camphor, two ounces; Volatile Oil of Rosemary, half an ounce; Alcohol, two pounds. Digest the soap in the alcohol for three days ; then add the camphor and oil to the strained liquor, agitating it." There is a similar composition in the London 78 TINCTURES. and Dublin Pharmacopoeias, under the name of Linimentum Saponis Compositum, three ounces of hard soap and one ounce of camphor being dissolved in a pint of spirit of rosemary. This is a stimulant of considerable efficacy, used as an external application, by friction, in strains and rheumatic pains. Tinctura saponis cum opio ; olim, Linimcntum Anodynurn. Tincture of Soap with Opium. " This is made in the same manner, and from the same ingredients, as the tincture of soap ; only adding at first one ounce of opium." It is used for the same purposes as the preceding tincture, and likewise as an anodyne in rheumatism and spasms of the muscles. It is frequently successful in relieving pain by topical application, though the relief is often only temporary. Tinctura senna: composita, olim Elixir Salutis. Tincture of Senna. (Tinct. Sennae, Ph. Lond. Dub.) " Take of the Leaves of Senna, two ounces; Root of Jalap, one ounce ; Coriander Seeds, half an ounce; Diluted Alcohol, three pounds and a half. Digest for seven days, and to the tincture strained through paper add four ounces of Refined Sugar." This forms a very excellent purgative tincture, less unpleasant in its taste than any of the other cathartic tinctures, not liable therefore to excite nausea, and at the same time operating sufficiently well. Its dose is one ounce or ten drachms. In the London and Dublin Pharmacopoeias it is prepared without the jalap, and is therefore less active. Tinctura toluiferas balsami ; olim, Tinctura Tolutana. Tincture of Tolu Balsam. (Tinct. Bals. Tolut. Ph. Dub.) " Take of Balsam of Tolu, one ounce and a half; Alcohol, one pound. Digest until the balsam is dissolved, and strain through paper." The tolu balsam is entirely soluble in alcohol; but as TINCTURES. 79 it is a substance of no activity, this tincture is scarcely used but on account of its flavour, and for making the syrup of tolu. Tinctura veratri albi. Tincture of White Hellebore. " Take of White Hellebore Root, eight ounces; Diluted Alcohol, two pounds and a half. Digest for seven days, and strain through paper." White hellebore is a medicine perhaps never prescribed internally, its operation is so violent. The dose of this tincture cannot exceed a few drops. Neither is it used as an external application. The following are the Tinctures peculiar to the London and Dublin Pharmacopoeias. Tinctura aurantii, Tincture of Orange Peel. Ph. Lond. Dub. " Take of Fresh Orange Peel, three ounces; Proof Spirit, two pints. Digest for three days, and strain." The alcohol is in this tincture impregnated with the flavour and bitterness of the orange peel, and it may be used as communicating flavour, or in combination with more powerful bitters. Tinctura camphors composita. Ph. Lond. " Take of Camphor, two scruples; Hard Opium in powder, Acid of Benzoin, of each one drachm; Proof Spirit, two pints. Macerate for fourteen days, and strain." The same composition, with the addition of a drachm of Essential Oil of Anise, (which used also to bean ingredient in the above formula, but has been left out, as its flavour is rather disagreeable,) has a place in the Dublin Pharmacopoeia, under the name of Tinctura Opii Camphorata. This is the tincture which has been known under the name of Paregoric Elixir, and is in common use as a pleasant opiate in catarrh, two tea-spoonfuls being take*! TINCTURES. 80 at bed-time. Half an ounce of it contains a grain of opium. It is therefore inferior in strength, but less harsh and stimulating, as has been already remarked, than the tincture which has a place in the Edinburgh Pharmacopoeia, under the same popular name of Paregoric Elixir. The London College have given it its present name, rather than the former one, of Tinctura Opii Camphorata, to lessen the risk of its being confounded with Tincture of Opium, in prescribing it. Tinctura capsici. Tincture of Capsicum. Ph. Lond. " Take of Capsicum Berries, an ounce; Proof Spirit, two pints. Macerate for fourteen days, and strain." Under this form capsicum may be employed as a stimulant and stomachic; and diluted, it may afford an easy mode of forming the capsicum gargle. Tinctura cardamomi composita. Compound Tincture of Cardamom Ph. Lond. Dub. " Take of Cardamom Seeds, Carraway Seeds, Cochineal, of each beat to powder, two drachms; Cinnamon Bark bruised, half an ounce; Raisins freed from the stones, four ounces; Proof Spirit, two pints. Macerate for fourteen days, and strain." There is a similar composition under the same name in the Dublin Pharmacopoeia, the raisins being omitted. With this omission, it is nearly the same with the Compound Tincture of Cinnamon of the Edinburgh Pharmacopoeia, and may be applied to the same uses. Tinctura cascarilla;. Tincture of Cascarilla Ph. Lond. Dub. "Take of Cascarilla Bark, four ounces; Proof Spirit, two pints. Macerate for fourteen days, and strain." Cascarilla is so little employed in modern practice, that there is scarcely any advantage in having its tincture as an officinal preparation. Tinctura cinchona; composita, Compound Tincture of Peruvian Bark. Ph Lond. Dub. " Take of Pale Peruvian Bark beat to powder, two ounces; Dried Orange Peel, an ounce and a half. Vir- TINCTURES. 81 ginian Snake-Root bruised, three drachms; Saffron, one drachm; Cochineal, two scruples ; Proof Spirit, twenty fluid ounces. Macerate for fourteen days, and strain." This is the composition which has been known under the name of Huxham's Tincture of Bark. It is more grateful than the simple tincture, and, from the substances added to the cinchona, is probably a better stomachic. It is principally in dyspeptic affections that it is employed, in a dose of two drachms taken occasionally. Tinctura humuli. Tincture of Hop. " Take of Hops, five ounces; Proof Spirit, two pints. Macerate for fourteen days, and strain." Hop having been introduced as a narcotic, the tincture affords a convenient form for its administration. It has been supposed to be nearly of the same strength as tincture of opium, but it requires in general to be given in a dose of from half a drachm to a drachm, to produce much sensible effect. Tinctura rhei composita. Compound Tincture of Rhubarb. Pharm. Lond. " Take of Root of Rhubarb cut, two ounces ; Liquorice root bruised, half an ounce ; Ginger Root cut, Saf - fron, of each two drachms; Water, a pint; Proof Spirit, twelve fluid ounces. Macerate for fourteen days, and strain." The principle in which the purgative quality of rhubarb resides, has been supposed to be more completely dissolved by water than by other solvents ; hence from the large proportion of water in this tincture, it is supposed this quality will be obtained more completely : while the proportion of alcohol will prevent spontaneous decomposition. Its medium dose as a purgative is an ounce. Tinctura scilljE. Tincture of Squill. Ph. Lond. Dub. " Take of Squill Boot, recently dried, four ounces: Proof Spirit, two pints. Digest for fourteen days, and strain." Vol. II. 12 82 TINCTURES. Squill, when employed as a diuretic, operates most effectually in substance: as an emetic or expectorant it is given under the form of the vinegar or syrup, the vinegar correcting its nauseous taste, if is not apparent what particular advantage is to be derived from a tincture of it, —a preparation in which the acrimony of the squill must be very imperfectly covered. The dose of this tincture is from twenty to sixty drops. Tinctura Valeriana:. Tincture of Valerian. Ph Lond. Dub. " Take of Valerian Root, four ounces ; Proof Spirit, two pints. Digest with a gentle heat for fourteen days, and strain." The active matter of valerian is sufficiently extracted by diluted alcohol. The powers of the menstruum probably however exceed those of the dissolved matter, and hence this tincture cannot be employed with much advantage. Tinctura Valeriana; ammoniata. Ammoniated Tincture of Valerian. Ph. Lond. Dub. " Take of Valerian Root, four ounces ; Aromatic Spirit of Ammonia, two pints. Digest for fourteen days and strain." This tincture may be more powerful than the preceding, from the impregnation of ammonia. It is employed in hysterical affections. Its dose is from one to two drachms. Tinctura zingiberis. Tincture of Ginger. Ph. Lond. Dub. " Take of Ginger, two ounces; Proof Spirit, two pints. Macerate for fourteen days, and strain." This tincture contains the pungency of the ginger, and may be used as an aromatic to conceal the flavour and taste, or promote the operation of other remedies. To obviate flatulence, ginger is generally taken in substance. Tinctura angustura. Tincture of Angustura. Ph. Dub. " Take of the Bark of Angustura in coarse powder, two ounces ; Proof Spirit, two pints. Digest for seven days, then strain the tincture." EXTRACTS. 83 Diluted alcohol dissolves the active matter of angustura ; and under this form it has been sometimes given in dyspepsia, in a dose of two drachms occasionally. Tinctura galbani. Tincture of Galbanum. Ph. Dub. " Take of Galbanum in small pieces, two ounces: Proof Spirit, two pints. Digest, them for seven days; then strain the tincture." This tincture has sometimes been used in hysteria, to obviate flatulence, in a dose of two to three drachms. It can scarcely be supposed to have any power. Tinctura moschi. Tincture of Musk. Ph. Dub. " Take of Musk, two drachms ; Rectified Spirit, one pint. Digest for seven days, and strain the tincture." This tincture can be employed only to communicate the odour of musk, and is therefore of little importance. Tinctura quassias. Tincture of Quassia. Ph. Dub. " Take of the Wood of Quassia rasped, one ounce ; Proof Spirit, two pints. Digest for seven days; then strain the tincture." The bitterness of quassia may be sufficiently extracted in this preparation These bitter tinctures appear, however, to be unnecessarily multiplied in the Pharmacopoeias, especially as from the action of the menstruum on the stomach, the form of tincture is not the best for the administration of this class of remedies. CHAPTER XIV. EXTRACTA.—EXTRACTS. Extracts are preparations obtained by digesting or boiling vegetable substances in water, alcohol, or proof spirit. The menstruum dissolves the active matter ol the vegetable; the tincture or decoction is strained, and is EXTRACTS. 84 evaporated until a mass of a stiff consistence is obtained* This is named an Extract,and either a watery or spiritous extract, as water or alcohol has been employed as the menstruum. If water has been used, the mucilage, extract, tannin, saccharine, and saline parts of the vegetable remain in the extract; if alcohol, the resin is its principal component part; and if proof spirit, all the fixed principles which water and alcohol are separately capable of dissolving, are obtained. It is evident, therefore, that the same mode of preparing these extracts, is not applicable to every vegetable substance. Where the virtues depend principally on the extract ortannin which the substance contains, the watery extract will be proper ; while, if it depend on a resinous part, the spiritous extract only will possess its virtues. It is to be observed, however, that in the preparation of these extracts, the virtues of the substances are almost always injured to a certain extent. The essential oil, on which their flavour and aromatic quality depend, are dissipated ; and in the preparation of the watery extracts, there is generally a partial decomposition of the active matter, by the necessary decoction. This preparation, therefore, is not now very frequently employed; and with the exception of some of the pure bitters, as gentian, or some of the saccharine vegetables, as liquorice, there is no medicine, perhaps, but what may be given with more advantage under some other form. The Edinburgh and Dublin Colleges preserve the distinction of watery and spiritous extracts: the London College do not observe it; and they have farther associated, with what are more strictly named extracts, the inspissated juices of vegetables, the consistence of these being similar ; and the only circumstance in which they differ, that in the one the matter naturally dissolved in the juice of the plant, in the other, the matter extracted by the operation of a solvent is obtained, is not, it has been conceivedjsufliciently important to constitute a distinction between them. 1 have adhered, however, to the arrange- ment of the Edinburgh Pharmacopoeia, and under the EXTRACTS. 85 chapter of Inspissated Juices have already introduced those which are peculiar to the London Pharmacopoeia. I.— Extracta per Aquam. — Extracts by Water. The directions for preparing these are given in the Edinburgh Pharmacopoeia, under the Extract of Gentian. The directions in the other Pharmacopoeias are essentially the same, a common water-bath being ordered for the inspissation ; the ext ract being stirred constantly as it becomes thick, and when prepared being kept with a little alcohol sprinkled on the surface. Extractum gentiana: lutejE. Extract of Gentian. (Extr. Gent, Ph. Lond. Dub.) " Take of Gentian Root, any quantity. Having cut and bruised it, add eight times its weight of Distilled Water. Boil to one half, and strain, expressing the liquor strongly. Reduce it immediately to the consistence of thick honey, by evaporation in a bath, of boiling water saturated with muriate of soda." This extract is intensely bitter, the quality of bitterness appearing in general not to be injured by the operation of decoction or evaporation It is generally used to form other medicines into pills, particularly those with which it coincides in medicinal virtues, as tonics and emmenagogues. In the same manner are prepared the following Ex tracts : Extractum florum anthemidis nobilis. Extract of Chamomile (Extr. Anthem. Ph. Lond. —Extr. Chamom. Ph. Dub.) The bitterness of Chamomile is rendered rather ungrateful in its infusion, by the flavonr of its essential oil. This is entirely dissipated by decoction, and the extract is, therefore, a pure and grateful bitter. It is scarcely applied, however, to any use. 86 EXTRACTS. Extractum poliorum cassias sennas. Extract of Senna. Senna has its activity much impaired by decoction. The extract, therefore, besides that it has no particular advantage, cannot be regarded as a proper preparation of it, and it is accordingly found not to be more powerful than the leaf in substance. Extractum radicis glycyrrhizas glabras. Extract of Liquorice Root. (Extr. Glycyrrh. Ph. Lond. Dub.) The active matter of this root consists chiefly of mucilage and saccharine matter, and suffers therefore little injury in this preparation. The extract is seldom prepared in the shops but on a large scale ; and this extract of commerce is usually in an impure state. In some of the foreign Pharmacopoeias, it is purified by solution in water, straining, and a new evaporation; and an extract either prepared in this way, or directly from the root itself, due care being taken in its preparation so as to have it pure, is now sold under the name of Refined Liquorice. It is evaporated so as to be perfectly hard, and is in common use as a demulcent in catarrh, being allowed to dissolve slowly in the mouth. Extractum ligni hasmatoxyli campechensis. Extract of Logwood. (Extr. Haematoxyl. Ph. Lond. Dub.) The astringency of the logwood is obtained with no sensible injury in this extract. It has been proposed to be employed as an astringent, in a dose from ten to twenty grains, but has never been established in use. Extractum radicis hellebori nigri. Extract of Black Hellebore Root. (Extr. Helleb. N. Ph. Dub.) The aqueous extract of this root is comparatively mild in its operation, and is even said to be milder than the root itself. In a dose from ten to twenty grains, it operates as a cathartic, and has been employed as such in mania, and in a smaller dose, as an emmenagogue, but its uniformity of operation cannot be depended on. The spiritous extract, which has a place in some of the EXTRACTS. 87 foreign Pharmacopoeias, is a more active medicine. It has been used as a hydragogue cathartic, and is the basis of Baccher's tonic pills, once highly celebrated in the treatment of dropsy. Extractum capitum papaveris somniferi. Extract of Poppy. (Extract. Papav. Ph. Lond.) This extract from the capsule of the popy retains its narcotic quality to a certain extent. It is, however, so far injured, that the extract is not uniform in strength, and is therefore little used. Sometimes it is employed in making the syrup of poppy, a drachm of it being dissolved in a pound of water, and boiled with a pound of sugar. Extractum foliorum rutas graveolentis. Extract of Rue. (Extr. Rutae, Ph. Dub.) As the virtues of Rue reside chiefly, if not entirely, in its essential oil, this extract must be regarded as an injudicious preparation. It is intended for administration in amenorrhcea, its dose being from ten to fifteen grains: but it has probably no power. The following watery extracts have a place in the Dublin or London Pharmacopoeia. Extractum aloes. Extract of Aloes. Ph. Lond. " Take of Socotorine Aloes in powder, half a pound ; Boiling Water, four pints, Macerate for three days with a gentle heat; then strain, and put the liquor aside, that the impurities may subside. Pour off the purified liquor, and evaporate, until it attain a proper consistence." The object of this preparation is not so much to separate the aloes from any impurities, for the socotorine aloes scarcely contains any, but to obtain a gummy extract with less resin, which is said to be equally purgative, less stimulating and less ungrateful. Its dose is ten or fifteen grains. EXTRACTS. 88 Extractum cinchona;, vulgo Corticis Peruviani. Extract of Peruvian Bark. Ph. Lond. Dub. " Take of Pale Peruvian Bark, in coarse powder, one pound; Water, one gallon. Boil to six pints, and strain the liquor while hot. In the same manner boil it four times, in the same quantity of water, and strain the liquors. Then reduce all these liquors, mixed together, to a proper consistence, by evaporation. " This extract ought to be kept soft, fit to form pills; and hard, so that it may be reduced to powder." The active matter of bark is in a great measure of an extractive and resinous nature, being more soluble in alcohol than in water; but the water, when assisted by a boiling heat, is capable of dissolving it; and as a great part of the bark in substance consists of inert ligneous matter, it might be supposed that some advantage is derived from this preparation. During the boiling and evaporation, however, it suffers a chemical change to a certain extent ; for the decoction itself becomes turbid, during boiling, from the dissolved matter becoming less soluble, a change probably analogous to that which takes place in several varieties of vegetable matter, exposed in a humid state, and at an elevated temperature, and the nature of which, so far as it has been determined, has been already explained (page 38.) Hence the extract obtained is far from being equal in efficacy to the quantity of bark from which it is prepared. Its medium dose is ten grains, which is supposed to be equivalent to half a drachm of the bark in substance, but from the uncertainty of its strength it is little employed. Extractum colocynthidis. Extract of Colocynth. Ph. Lond. " Take of the Pulp of Colocynth, one pound; Water, a gallon. Boil to four pounds and strain the liquor while hot; then reduce it by evaporation to the proper consistence." The active matter of colocynth is so far extracted by water by decoction, that the extract has a cathartic quality. It is less powerful, however, and has been supposed EXTRACTS. 89 to be less irritating than the pulp itself. Its dose is from six to ten grains. Extractum colocynthidis compositum. Compound Extract of Colocynth. Ph. Lond. Dub.) " Take of the Pulp of Colocynth cut, six drachms; Socotorine Aloes in powder, an ounce and a half; Scammony in powder, half an ounce; Cardamom Seeds in powder, a drachm ; Hard Soap, three drachms; Boiling- Water, two pints. Macerate the pulp of colocynth in the water, with a gentle heat, for four days. Strain the liquor, and add to it the aloes, scammony and soap; then evaporate until it attain a proper consistence, and towards the end of the evaporation, mix in the cardamom seeds." This is the officinal preparation which has long had a place in the Pharmacopoeias, under the name of Extractum Catharticum. It is a combination of the more powerful cathartics ; and as these operate more effectually, and with less irritation when combined, than when one alone in a large dose is employed, the composition is well adapted for administration in cases where it is difficult to excite purging. It used formerly to be prepared by employing diluted alcohol as the solvent, not only of the colocynth, but also of the resinous substances, and evaporating the solution; the present method is more economical, and will probably afford a product more uniform in strength. The extract is usually given in doses of from five to ten, or fifteen grains, repeated at short intervals until it produce purging. Its power may also be safely promoted, by adding a portion of calomel. Extractum humuli. Extract of Hop. Ph. Lond. " Take of Hops, half a pound ; Water, a gallon. Boil to four pints, and strain the liquor while it is hot; then reduce it by evaporation to the proper consistence." Hop has been introduced into practice as a narcotic, possessing also from its bitterness a degree of tonic Vol. II. 13 90 EXTRACTS. power. The bitterness will be obtained in this extract, but it is probable that the narcotic power is impaired, and that in this property it will not be uniform in strength. The dose of this extract is from five to fifteen grains. Extractum opii. Extract of Opium. Ph. Lond. (Extractum Opii Aquosum, Ph. Dub.) " Take of Opium cut into pieces, half a pound ; Water, three pints. Add to the opium a small quantity of the water, and macerate for twelve hours that it may become soft; then add gradually the remaining water, triturate until they are intimately mixed, and put aside the mixture that the impurities may subside: then strain the liquor, and evaporate it to the proper consistence." Any process of this kind designed to purify opium, is altogether superfluous, for the impurities of the opium of commerce are inconsiderable, and neither alter its powers, nor add materially to its bulk. And if such processes are designed to correct any of the qualities of the opium, whence the unpleasant symptoms which sometimes follow from its administration are supposed to arise, they probably rest on inaccurate views of its operation. The active matter of opium is not entirely extracted by water. In the present process, therefore, the product must differ from the crude opium, and it would require clinical experience more extensive and accurate than we yet have, to ascertain correctly its real powers. It must, besides, be altered, and rendered at the same time uncertain in strength by the chemical change which it will suffer during its inspissation. Even when the active principles of the opium have been extracted by diluted alcohol, though the solvent is more powerful, requires less heat for its evaporation, and counteracts to a certain extent the action of the air, still the inspissated mass is found to be inferior in strength to opium in its unpurified state, and this must be still more the case in the present process, where water only is employed. It may therefore be questioned whether any EXTRACTS. 91 preparation of this kind retains its place with propriety in the Pharmacopoeias. Extractum rhei. Extract of Rhubarb. Ph. Lond. " Take of the Root of Rhubarb bruised, one pound; Diluted Alcohol, a pint; Water, seven pints. Macerate for four days with a gentle heat, and put aside the liquor that the impurities may subside; pour it off when clear, and reduce it by evaporation to the proper consistence." The purgative power of rhubarb is usually considered as being more peculiarly extracted by water, and may therefore be obtained in this extract. It will equally be obtained, however, in the simple infusion, which, as being an extemporaneous preparation, is preferable to this one, that besides the change that may be produced in it by inspissation, must be farther liable to decomposition when kept in a soft state. Extractum sarsap arillac. Extract of Sarsaparilla. Ph. Lond. " Take of Sarsaparilla Root cut, a pound ; Boiling Water, a gallon. Macerate for twenty-four hours ; then boil to four pints, and strain the liquor while hot; lastly, reduce it by evaporation to the proper consistence," Sarsaparilla being usually given under the form of watery decoction, there appears to be no particular advantage in preparing from this an extract, as the decoction may be brought to any state of concentration, by using an increased proportion of the root, or continuing the boiling for a longer time. And a watery extract, mucilaginous as this is, besides the injury it will probably suffer in its inspissation, will farther be liable to spontaneous decomposition on keeping, and is therefore unfit for an officinal preparation. Extractum taraxaci. Extract of Dandelion. Ph. Lond. Dub. " Take of the Fresh Root of Dandelion bruised, a pound ; Boiling Water, a gallon. Macerate for twentytour hours ; then boil to eight pints, and strain the liquor while hot; lastly, evaporate it to the proper consistence." EXTRACTS. 92 The recent root of dandelion has been ranked as au aperient and diuretic. The expressed juice, or decoction of the root, has been employed as a remedy in dropsy, biliary obstructions and induration of the liver, and, according to Bergius, has proved frequently successful where other remedies had faded Whatever may be the powers of the plant, it may be doubted if the form of the watery extract be the best for its administration. Extractum Valeriana;. Extract of Valerian. Ph. Dub. " Take of Valerian Root in coarse powder, six ounces ; Boiling Water, three pints. Digest for twentyfour hours in a close vessel with a moderate heat; press out the liquor, and reduce it to a proper consistence by evaporation." The medicinal powers of Valerian appear to be connected with the principle in which its odour resides; and as this must be in a great measure dissipated by evaporation, it may be doubted if this is a form of preparation properly adapted. It can a least have no advantage over the extemporaneous infusion or decoction. Extractum cacuminum absinthii. Extract of the Tops of Wormwood. Ph. Dub. This extract prepared in the usual manner from the flowering tops of the wormwood is intensely bitter ; and the unpleasant odour of the plant is dissipated during the evaporation. It may be substituted medicinally for extract of gentian. It is sometimes used, instead of hops, to give bitterness to fermented liquors. Extractum cacuminum genista;. Extract of Broom Tops. Ph. Dub. The infusion of the tops of the broom has a degree of diuretic power, whence it has been employed as a remedy in dropsy. The extract can scarcely be supposed to have much power, and it is now expunged from the Edinburgh Pharmacopoeia, where it formerly had a place. EXTRACTS. 93 Extractum radicis jalapas. Extract of Jalap Root, Ph. Dub The active matter of jalap is partly resinous, and must therefore be imperfectly extracted by water. The extract thus prepared may be milder than the root, but must be liable to be uncertain in strength. A resinous extract is prepared by the action of diluted alcohol, which has a place in all the Pharmacopoeias, and which will be a more active preparation, though neither of them probably is of much utility. Extractum corticis quercus. Extract of Oak Bark. Ph. Dub. In this extract the astringency of the oak bark will be obtained probably with little injury, and consisting principally of tannin, it will not be very liable to spontaneous decomposition. It can have scarcely any advantage, however, but what may be equally obtained from the decoction. Extractum poliorum sABiNiE. Extract of Leaves of Savin. Ph. Dub. The medicinal powers of this herb seem in a great measure to depend on its essential oil, and as this must be dissipated during the evaporation, the extract must be comparatively an inactive preparation. It is never used. II.— Extracta per Aquam et Alcohol. — Extracts by Water and Alcohol. The directions for preparing these are given under the first of them, the Extract of Bark. Extractum cinchona: officinalis. Extract of Peruvian Bark. (Extr Cinch Piesin. Ph. Lond. Dub.) " Take of Peruvian Bark in powder, one pound; Alcohol, four pounds. Digest for four da\s, and pour off the tincture. Boil the residuum in five pounds of distilled water for a quarter ot an hour, and strain the EXTRACTS. 94 decoction while hot through linen. Repeat this boiling and straining with an equal quantity of distilled water, and reduce the liquor by evaporation to the consistence of thin honey. Draw off the alcohol from the tincture by distillation, until it is reduced to a similar consistence. Then mix the liquors thus inspissated, and reduce to a proper consistence by a bath of boiling water, saturated with muriate of soda." This preparation will probably be more active than the watery extract of bark. By the joint action of the alcohol and water, all the principles of the bark are extracted, and nothing remains but the inert ligneous fibre. And in the subsequent evaporation, the dissolved matter suffers less injury, partly from less heat being required to bring it to the due consistence, and partly perhaps from the alcohol resisting the oxygenation of the extract. It is, however, much more expensive; and the extract of bark to be found in the shops is almost always that which is prepared by the other formula. The dose of the spiritous extract is ten grains, and it affords a very convenient vehicle for combining bark with the more active preparations of iron in the form of pin. Extractum radicis convolvuli jalapas. Extract of Jalap. (Extr. Jalap Resin. Ph. Dub. Lond.) This is ordered to be prepared in the same manner as the Extract of Bark. From the solvent employed both the resinous and mucilaginous parts of the jalap root are extracted, and it is therefore a more active preparation than the watery extract of jalap already noticed. It exerts its cathartic operation fully in a dose of ten or twelve grains, but it has no particular advantage. B»esides these two, which have a place both in the Dublin and the London Pharmacopoeias, there are other two spiritous extracts admitted by the Dublin College. DISTILLED WATERS. 95 Extractum cascarilla: resinosum Resinous Extract of Cascarilla. Ph. Dub. This is prepared from the cascarilla bark, in the same manner as the resinous extract of cinchona is prepared. It may contain the active matter of the cascarilla, and may be given as a bitter and tonic, in the dose of a scruple ; but there does not appear to be any peculiar advantage in employing this remedy under this expensive form. Opium purificatum. Purified Opium. Ph. Dub. " Take of Opium cut into small pieces, one pound; Proof Spirit, twelve pounds. Digest them with a gentle heat, stirring them frequently until the opium is dissolved : strain the tincture through paper, and distil it in a retort until the spirit is abstracted ; pour out the remaining liquor, and evaporate it until the extract become of a proper consistence. Purified opium must be kept in two states, one soft, so as to be fit for forming pills, the other hard, so as to be capable of being reduced to powder." The objections to the purification of opium by the action of water have been already stated. In this process, as the power of the solvent is greater, and the degree of heat necessary to evaporate it less considerable, it is probable that the opium will suffer less change. Still we cannot be certain of its real power in this state, and the process is expensive, and altogether superfluous. CHAPTER XV. AQTJJC STILLATITI^E.—DISTILLED WATERS. Several of the principles of vegetable matter are so far volatile as to be elevated in vapour at the temperature of 212°; hence when water is distilled trom them. DISTILLED WATERS. 96 it is frequently impregnated with their taste and odour, and sometimes even with their more active powers. I he odour, and frequently the pungerury of plants reside in their essential oil; and this being always volatile at this temperature, the aromatic plants in which essential oil is most abundant, communicate these qualities to water distilled from them, a portion of the oil being retained in solution by the water. The acrid principle of some vegetables appears likewise to be so far volatile as to rise in distillation with water; and the prussic acid, in which the narcotic power of the bitter almond, cherry laurel, and similar plants resides, is also obtained by the same process : but these vegetables are comparatively few, and there are no officinal distilled waters having a place in the Pharmacopoeias possessed of any important power; they are designed, from their flavour and agreeable pungency, to serve merely as vehicles for the exhibition of more active remedies, and all of them owe these qualities to the small quantity of essential oil which they hold dissolved. Recent vegetables are in general more proper for distillation than after being dried, the water they afford being more grateful. They are therefore ordered in this state when they can be procured in it by the Edinburgh and Dublin Colleges. The London College on the contrary, order them to be used dried, as they cannot be procured fresh at all seasons of the year. When fresh, they in general impregnate sufficiently with their flavour and taste, three times their weight of water ; when dry, double that quantity. As much must always be employed, as when drawn off by distillation a sufficient quantity shall remain in the still to prevent any part of the vegetable matter being scorched, and communicating empyreuma to the distilled water, the distillation being continued as long as the water that comes over has any taste or smell of the vegetable from which it is distilled. The flavour of the more delicate plants is injured by this operation ; and these distilled waters are in general less grateful to the stomach than the infusions of the vegetable matter which yields them. DISTILLED WATERS. 97 Distilled waters are liable to a species of decomposition, the nature of which has never been weli determined. When long kept, they become viscid, and at the same time somewhat sour, —a proof that they hold dissolved some species of vegetable matter besides the minute portion of essential oil. To counteract this change, and preserve them more effectually in a proper state, a small quantity of alcohol, half an ounce to each pouud of the distilled water, is ordered to be added to them. Aq.ua distillata. Distilled Water. Pharm. Ed. Lond. Dub. " Distil water in clean vessels until about two-thirds have distilled over." Water does not occur in nature perfectly pure, but has generally a sensible impregnation of saline and earthy matter. Spring water which is purest, contains a little carbonate of lime, and muriates of lime and soda : river water contains sulphate and carbonate of lime, and muriate of soda; and well water, sulphate and carbonate of lime in larger quantity. For some purposes in Pharmacy, it is necessary to use water free from these substances, particularly in the solution of some earthy and metallic salts, several of which are decomposed by them, and if they are given in small doses, may, by such decompositions, be rendered nearly inert. In preparations too, where much water is evaporated, as in the formation of extracts, it has been judged preferable to employ distilled water, as the residual matter of common water will remain mixed with the product of the process, and uselessly add to its bulk, or even in some cases produce in it some chemical change. It is for these purposes that distilled water is ordered in the Pharmacopoeias; but except where the use of it is rendered necessary from these circumstances, it ought not to be employed, as from losing in the distillation much of the air that it holds loosely dissolved, it is always vapid and unpleasant. The process should be conducted with rather a gentle Vol. II. 14 DISTILLED WATERS. 98 heat, and ought not to be continued longer than until two-thirds of the water have discHled, as otherwise a minute portion of the saline matter might be brought over in the distillation. Aqua citri aurantii. Water of Orange Peel. " Take of the rind of the Orange, fresh, two pounds. Add as much water, that when ten pounds have been drawn off* by distillation, a sufficient quantity shall remain to prevent empyreuma. After due maceration, distil ten pounds." This distilled water has none of the bitterness of the orange peel, but merely its flavour, and is so little used, that it is not kept in the shops. In the same manner are prepared the following distilled waters: Aqua citri medico. Water of Lemon Peel, —ten pounds of water being drawn from two pounds of the fresh rind of the lemon. Like the preceding one, it has merely a slightly agreeable flavour, and is scarcely used. Aqua corticis lauri cassia, Water of Cassia Bark. Aqua corticis cinnamomi. Water of Cinnamon Bark, —ten pounds of water being distilled from a pound of each bark. The cinnamon water only has a place in the London and Dublin Pharmacopoeias. The cassia water, when not prepared too pungent, can scarcely, however, be distinguished from that of the cinnamon, the essential oil of both these barks having a flavour nearly the same. The cassia water, therefore, being much less expensive than the cinnamon, is always substituted for it. It has the pungency and aromatic flavour of the cassia, and is hence in very common use to cover the ungrateful taste and flavour of other medicines. It is also sometimes given alone as an aromatic and stimulant. Aqua Mentha piperita floiientis. Peppermint Water. (Aq. Menth. Piperit. Ph. Lond. Dub.) — DISTILLED WATERS. 99 Ten pounds of water are drawn by distillation from three pounds of green peppermint. It is strongly impregnated with the flavour of the herb, and is very frequently used in mixtures to cover the flavour of other medicines. It is also frequently taken alone as a carminative. Aquje MENTHiE pulegii florentis. Pennyroyal Water. (Aq. Pulegii, P. Lond. Dub.) —Ten pounds of water are distilled from three pounds of the green herb. It has a flavour and taste similar to that of the peppermint, and is used for the same purposes. Aqua fructus myrti pimento. Pimento Water. (Aq. Piment. Ph. Lond. Dub.) —Ten pounds of water are distilled from half a pound of the Jamaica pepper. It has the flavour of the Jamaica pepper, and its aromatic quality; but as this is not very pleasant it is not often used. Aqua petalorum centifolije. Rose Watei. (Aq. Rosce, Ph. Lond. Dub.) —Ten pounds of water are drawn from six pounds of the fresh pale rose flowers. The water has all the flavour of the rose, and as it has no pungency or acrimony, it is often used for external applications, as in solutions of acetate of Lead, or sulphate of zinc for collyria. There are a few Distilled Waters peculiar to the London or the Dublin Pharmacopoeias, of so little importance, however, as to require scarcely more than enumeration. Aqua anethi. Dillseed Water. Ph. Lond.—Its flavour is rather unpleasant, and it has little pungency. Aqua carui. Caraway Water. Ph. Lond.—This has a considerable share of aromatic flavour and pungency, and may be employed as a carminative. Aqua foeniculi. Fennel Water. Ph. Lond. Dub.-— This has merely the weak flavour of the seeds, with little warmth. Aqua Mentha viridis. Spearmint Water. Ph. Lond. (Aq. Menth. Sativ. Ph. Dub.) —Its flavour and taste are so similar to those of peppermint or pennyroyal* that it must be regarded as superfluous. 100 DISTILLED SPIRITS. CHAPTER XVI. SPIRITUS STILLATITII.—DISTILLED SPIRITS. Alcohol dissolves the essential oils of vegetables in much larger quantity than water does, and it might therefore be supposed that it may be more strongly impregnated with them by distillation, and hence possess in a much greater degree the aromatic flavour and pungency of the plant from which it is distilled. It is seldom, however, that this is the case; and from many vegetables alcohol acquires by distillation a weaker impregnation than water. Tins is owing to its greater volatility. All the essential oils are volatilized at a temperature of 212°, and must therefore rise with water in distillation, and impregnate it to the extent in which it can dissolve them. But there are many of them not volatilized at the temperature at which alcohol boils, and when distilled, therefore, from the plants containing them, it comes over weakly impregnated with their odour or pungency. To obviate this, diluted alcohol, or proof-spirit as it is named, is employed in the distillation. It is macerated on the vegetable substance and is then distilled; the alcohol rises first nearly pure, but as the distillation proceeds the liquor requires always a higher temperature to cause it to boil: the vapour therefore is more largely impregnated with the essential oil, and towards the end of the distillation the whole of it is brought over with the last portion of water; and the spirit, which has previously been distilled, being mingled with this, forms a transparent solution. This forms a distilled spirit. There are at least only two in which pure alcohol is the solvent, —the spirit of lavender and spirit of rosemary, the essential oils of these plants being sufficiently volatile to be elevated at the temperature at which alcohol distils. Distilled spirits are preparations of no great importance. Like the distilled waters they serve merely as DISTILLED SPIRITS. 101 vehicles for the administration of more active medicines, the taste and flavour of which they cover or render more grateful ; or they are occasionally employed as grateful stimulants, to relieve nausea or flatulence. The directions for preparing them are given, in the Edinburgh Pharmacopoeia, under the first of them. Spiritus cari carui. Spirit of Can-away. (Spirit. Carui. Ph. Land. Dub.) " Take of Carraway Seeds bruised, half a pound. Diluted Alcohol, nine pounds. Macerate during two davs in a close vessel; then add a sufficient quantity of water to prevent empyreuma, and draw off nine pounds by distillation." In the same manner are prepared the following spirits, nine pounds being drawn from the quantities affixed to each Spiritus corticis lauri ciinnamomi. Spirit of Cinnamon Ph. Ed. Lond. Dub. Bark of Cinnamon, one pound). SpIKITUS MENTHA PIPERITA ELORENTIS. Spirit of Peppermint. Ph. Ed. Lond. Dub. (Herb of peppermint, one pound and a half). Sphutus nocis MVRiSTiOiE mosch atje. Spirit of Nutmeg. Ph. Ed. Lond. Dub. (Nutmeg bruised, two ounces). Spiritus fructus myrti pimento. Spirit of Pimento. Ph. Ed. Lond. Dub. (Fruit of pimento, bruised, half a pound). To these may be added the following from the London Pharmacopoeia, which are prepared in the same manner: Spiritus anisi. Spirit of Anise. Spiritus viridis. Spirit of Spearmint. Spiritus pulegii. Spirit of Pennyroyal All these spirits have the aromatic flavour, and to a DISTILLED SPIRITS. 102 certain extent the pungency of the vegetables from which they are prepared. They require, therefore, no particular observations. Of Compound Spirits, the following have a place in the Pharmacopoeias: Spiritus juniperi communis compositus. Compound Spirit of Juniper. Ph. Ed. Lond. Dub. " Take of Juniper Berries bruised, one pound ; Carra- Way Seeds, Fennel Seeds, of each bruised one ounce and a half; Diluted Alcohol, nine pounds. Macerate for two days; and, having added as much water as is sufficient to prevent empyreuma, draw off nine pounds by distillation." This is a grateful cordial spirit, which has been used as a carminative, and as a stimulant and diuretic in dropsy. Spiritus anisi compositus. Compound Spirit of Anise. Ph. Dub. " Take of Anise Seeds, Angelica Seeds, of each bruised half a pound ; Proof Spirit, one gallon ; Water as much as is sufficient to prevent empyreuma. Distil one gallon." This is similar to the preceding spirit, milder and perhaps less grateful. It has also been used as a carminative. Spiritus armoracije compositus. Spirit of Horse-Radish. Ph. Lond. (Spiritus Raphani Compositus. Ph. Dub. " Take of fresh Horse-Radish root cut, dried Orange Peel, of each one pound ; Nutmegs bruised, half an ounce ; Proof-Spirit a gallon ; Water, as much as is sufficient to prevent empyreuma. Macerate for twenty-four hours, then distil a gallon with a slow fire." There was formerly in this composition two pounds of fresh scurvy grass, and this is still retained by the Dublin College. This compound spirit was formerly recommended as an antiscorbutic. It has justly fallen into disuse. DISTILLED SPIRITS. 103 There remain, lastly, those Distilled Spirits prepared with Pure Alcohol. Spiritus lavendulas spice. Spirit of Lavender. Ph. Ed. Lond. Dub. " Take of Fresh Lavender Flowers, two pounds ; Alcohol, eight pounds. Draw off seven pounds by distillation with the heat of a water-bath." This oil of Lavender is sufficiently volatile to be elevated with alcohol in vapour, and it is completely dissolved by it. The spirit is used principally as a grateful stimulating perfume, which gives relief in headach, drawn up the nostrils, or applied to the forehead. Spiritus lavenduljE compositus. Compound Spirit of Lavender. Ph. Ed. Lond. Dub. " Take of Spirit of Lavender, three pounds ; Spirit of Rosemary, one pound; Cinnamon Bark bruised, one ounce ; Cloves bruised, two drachms; Nutmeg bruised, half an ounce; Red Saunders Wood rasped, three drachms. Macerate seven days and strain." In the formula given by the London College the cloves are omitted. This tincture is a grateful cordial and stimulant in common use, for relieving languor and faintness. Its dose is thirty or forty drops, taken on a piece of sugar or in a cupful of water. Spiritus rorismarini officinalis. Spirit of Rosemary. Ph. Ed. Land. Dub. 11 Take of Fresh Rosemary Tops, two pounds; Alcohol, eight pounds. Draw off seven pounds by distillation by the heat of boiling water." The London College employ diluted alcohol in the preparation of this spirit. Spirit of Rosemary is a very fragrant perfume, and is in common use for the same purposes as the simple Spirit <*f Lavender. 104 DISTILLED SPIRITS. Alcohol. Alcohol. Spiritus Vinosus Rectificatus. Rectitied Spirit of Wine. There is no process given in the Edinburgh Pharmacopoeia for the preparation of alcohol. It is supposed to be procured from those who prepare it on a large scale, and is inserted in the catalogue of the articles of the Materia Medica, as of the specific gravity .835, this being a strength at which it can be procured without difficulty, and being sufficient for any purpose to which it requires to be applied in Pharmacy. It is procured of this strength from any of the spiritous liquors of commerce by slow distillation with a gentle heat, a portion of sub-carbonate of potash heated being previously added to abstract the water more effectually from the spirit. It is usually submitted to a second distillation, and a little alum is frequently added previous to this, to remove any of the alkali which might be held in solution in the spirit obtained by the first distillation. The London and Dublin Colleges, while they have also inserted alcohol of this strength, under the name of Rectified Spirit, in the catalogue of the articles of the Materia Medica, have given a process to obtain it more concentrated for particular purposes. The following are the directions in the London Pharmacopoeia: Take of Rectified Spirit a gallon ; Sub-carbonate of Potash, three pounds. To the spirit add a pound of the sub-carbonate of potash previously heated to 300 degrees, and macerate for twenty-four hours, shaking frequently ; then to the spirit poured off, add the remaining portion of the sub-carbonate of potash heated to the same degree ; lastly, distil the alcohol from a water-bath, and preserve it in a vessel well stopped. The specific gra vity of alcohol is to that of distilled water as 815 to 1000. The process in the Dublin Pharmacopoeia is nearly the same. A gallon of rectified spirit is mixed with an ounce of pure potash; a pound of the potash of commerce heated is added, and they are digested in a close vessel for three days, being frequently agitated: to the spirit VOLATILE OILS. 105 poured off, half a pound of dried muriate of lime is added, and it is distilled with a gentle heat. The speciiie grav ity of the product is .815. The concentration of the alcohol in both processes is obviously obtained by the action of substances having a strong affinity to water, —the sub-carbonate of potash, and the muriate of lime ; these attract it from the spirit, and counteract its volatility so as to prevent its rising in the distillation. The muriate of lime exerts this agency most powerfully; and by repeated distillation from it, alcohol has been brought to its highest state of concentration, its specific gravity being so low as .800 or 798, at the temperature of 60°. Alcohol, rectified even so highly as is ordered by the London and Dublin Colleges, is required for very few pharmaceutic processes; and hence, in the greater number of their officinal preparations, rectified spirit, that is, alcohol of the specific gravity of .835, is directed to be employed. The proof spirit of the Edinburgh College, formed from equal parts of rectified spirit and water, is of the specific gravity of .935. That of the London and Dublin Colleges is stated at .930, and will be obtained of this strength by mixing four parts by measure of rectified spirit with three parts of water. The properties of alcohol as an agent in pharmacy, and its medicinal applications, have been al readv enumerated. CHAPTER XVII. . OLEA VOLATILIA, OLIM OLEA STILLATITIA VEL ES SENTIALIA.—VOLATILE OILS, FORMERLY DISTILLED OR ESSENTIAL OILS. Essential oil, as a proximate principle of vegetables, has already been considered, and its distinctive properties pointed out. As yielded by different vegetables, its chemical characters are nearly uniform: but th» Vol II. 15 106 VOLATILE OILS. oils of cliff brent plants vary in their sensible qualities, particularly in those of colour, consistence, odour, and taste. Their odour is that of the plant from which they are procured; their taste also is frequently the same, particularly in those plants named aromatic, and it is always pungent and acrid; their colours are shades of yellow, green and brown ; they are usually liquid, but sometimes of a thick consistence. In a few cases, these oils, existing in distinct vesicles, can be obtained by expression. Usually they are diffused through the vegetable matter, so as to render this impracticable; they are then obtained by distillation; the plant being distilled with a portion of water, not larger than what is necessary to avoid cmporeuma. The oil is volatilized with the watery vapour; and though a portion remains dissolved, yet from the sparing quantity of water employed, the greater part is collected apart, either, according to its specific gravity, floating on the surface, or having subsided to the bottom. In performing the operation in the large way, the same water is repeatedly put into the still, by which the loss from the oil being dissolved is in a great measure avoided. The product of oil is very different from different plants; and it is to be remarked, that the most odorous and pungent plants do not afford the largest quantity, even where the oil is the principle in which the odour or pungency resides ; —the petals of the rose for example, or the bark of cinnamon, affording a quantity extremely small, though in the one of" these the oil has the entire flavour of the flower, and the other the aromatic warmth of the bark. The quantity and quality of the oil are also influenced by the circumstances of climate, soil and season ; the rich aromatic oils being generally more fragrant from the plant when growing in a warm climate and dry soil, than under the reverse of these ; and the oil afforded by the aromatic vegetables of this climate is in general stronger, and in larger quantity, in a dry than in a wet season. The oil at its first distillation has frequently an odour less grateful than after it has been kept for some time; by age, however, its flavour is improved. If the VOLATILE OILS. 107 air has not been carefully excluded it at length becomes thick; some deposite a little camphor, and others, when distilled anew, yield an oil similar to the original, a resinous substance being left. The essential oils of commerce are sometimes adulterated, either by the addition of a cheaper oil, as that of turpentine, of an expressed oil, or of alcohol. These frauds are easily detected, —the first by the smell, when the adulterated oil is dropped on paper, and heated so far as be volatilized; the second, by the oil forming a greasy spot when dropped on paper, which remains so even after heat has been applied; the third, by the oil, when dropped on water, forming a milky, instead of a transparent film on the surface of the water. Essential oils are seldom applied to answer any important indication, having scarcely any other powers than those of aromatic warmth and pungency. If used alone to relieve flatulence or nausea, they may be diffused in water by the medium of mucilage and sugar, or dissolved in alcohol, and the solution diluted with water. More generally they are employed as corrigents, to improve the taste and flavour of ungrateful medicines, to cause these to sit easier on the stomach, or to obviate nausea, or any unpleasant symptom they may be liable to produce. The following general rules with regard to the preparation of these oils are given in the Edinburgh Pharmacopoeia. " These oils are to be prepared in the same manner as the distilled Waters, except that a smaller quantity of water is to be added. Seeds and roots are to be previously bruised or rasped. The oil is brought over with the water, and, according as it is lighter or heavier, floats on the surface, or falls to the bottom, and is afterwards separated. " It is also to be observed with regard to the preparation of distilled waters and oils, that, according to the quality of the substances, their texture, the season of the year, and similar circumstances, so many differences must arise, that it is scarcely possible to give any certain VOLATILE OILS. 108 and general rules which shall apply strictly to every example. Many tilings therefore are omitted, to be regulated according to the judgment of the operator, the most general precepts only being delivered." To tne general rules given by the London and Dublin Colleges, which are similar, it is added that the water which is produced in the distillation of the oils of carraway, peppermint, spearmint, pennyroyal, pimento, and sweet fennel, may be preserved for use, as it is sufficiently impregnated with the essential oil. The following oils are those inserted in the Edinburgh .Pharmacopoeia, and with the exception of the oils of savin and sassafras, they have a place likewise in the London and Dublin Pharmacopoeias. Oleum baccarum juniferi communis. Oil of Juniper genuine, this oil has the flavour of the juniper berries, and is soluble in alcohol. There is generally substituted for it in the shops an oil distilled from some species of turpentine much less grateful, which alcohol does not dissolve. Oleum juniferi Oil of Savine.—This plant yields more essential oil than any other does, two pounds affording not less than five ounces. The virtues of the savine seem also to depend on it, as the essential oil is said to be a powerful emmenagogue, in a dose from three to ten drops. It is however very little used. Oleum spicarum florentium Lavandula Oil of Lavender.—This oil is used principally on account of its flavour. Oleum radicis lauri sassafras. —Oil of Sassafras. This is the heaviest of the essential oils; its odour is somewhat fragrant, and its taste warm, but it has no quality that renders it of much value. Oleum menth/e piperita florentis. Oil of Peppermint.—This is one of the most pungent of the essential oils, and at the same time excites a peculiar sensation of coolness. It is a common and convenient remedy to relieve flatulence and anorexia, under the form of what is named Essence of Peppermint,— VOLATILE OTLS. 109 a solution of one part of the oil in seven parts of alcohol ; the dose of this being fifteen or twenty drops in a cupful of water. Oleum fructus myrti pimento. Oil of Pimento —This oil having the flavour of the Jamaica pepper, is sometimes used on account of this flavour. Oleum seminum PiMPiNELLJE amsi. Oil of Anise. —This oil is of a light colour, and has rather an unpleasant smell. It congeals even at a very moderately cold temperature. It has less pungency than any of the other essential oils, and is therefore well adapted to the purpose to which it is usually applied, that of relieving flatulence and the symptoms arising from it in children, a little of it being rubbed with sugar, and mixed with the child's food. The common proportion is ten or fifteen drops of the oil to two ounces of sugar. Ol EUM SUMMITATUM FLOKEN IUM RORISMARINI officinalis, Oil of Rosemary.—The odour of this oil is less grateful than when it is diluted with alcohol in the form of spirit of rosemary. It is sometimes used in ointments as a perfume, and it enters as a stimulant into the composition of the soap liniment. Besides these, a few other Volatile Oils have a place in the London and Dublin Pharmacopoeias. Oleum amhemidis. Oil of Chamomile. Ph. Lond. —This oil has an unpleasant flavour, and is applied to no use. Oleum carui. Oil of Carraway. Ph. Lond. Dub. — This is one of the most grateful of the essential oils, and well adapted to act as a carminative, or to communicate an agreeable pungency, and cover the flavour of unpleasant remedies. Oleum men vhm viridis. Oil of Spearmint. Ph. Lond. Dub. —The flavour of this oil is similar to that of peppermint, rather less grateful, and its taste is less pungent. Oleum origani. Oil of Origanum. Ph. Lond. Dub. —This is occasionally used as a perfume, though less grateful than the oil of lavender. VOLATILE OILS. 110 Oleum pulegii. Oil of Pennyroyal. Ph. Lond.— This oil resembles the oil of peppermint and spearmint, and may be regarded as superfluous. Oleum eoemculi dulcis, Oil of sweet Fennel. Ph. Dub.—The flavour of this oil is similar to that of Anise. Oleum rutje. Oil of Rue. Ph. Dub.—The flavour of oil of rue is ungrateful, and though it has been regarded as an emmenagogue, it is altogether discarded from use. Under the chapter of Volatile Oils are inserted some other preparations besides the Essential Oils of Plants. Oleum succini et acidum succini. Oil of Amber and Acid of Amber. (01. Succini. Ph. Lond. Dub.— Acid Succini. Ph. Dub.) " Take of Amber in powder, Pure Sand, equal parts. Put them mixed together into a glass retort, of which they shall fill one half. Having adapted a large receiver, distil from a sand-bath, with a fire gradually raised. First, a watery liquor with a little yellow oil will distil over; then a yellow oil with an acid salt ; afterwards a reddish and black oil. Pour the liquor out of the receiver, and let the oil be separated from the water. Let the acid salt, collected from the neck of the retort and the sides of the receiver, be pressed between folds of bibulous paper, and freed from the adhering oil. Then purify it by solution in hot water and chrystallization." Oleum sueciNi purissimum. Purified Oil of Amber. " Distil Oil of Amber mixed with six times its weight of Water, from a glass retort, until two-thirds of the water have passed into the receiver. Then separate this purified volatile oil from the water, and keep it in vessels well stopped." The Dublin college retain both the Acid and Oil of VOLATILE OILS. 111 Amber, and give nearly the same directions for their preparation. The Loudon College admit the oil only. Amber is a bituminous substance found in the layers of bituminated wood, or in fragments or masses on the sea shore in different countries, the origin or natural formation of which is not well ascertained. It is also possessed of peculiar characters ; for although it approaches to the vegetable resins in a number of its properties, it differs in others, and differs remarkably in the products it affords when decomposed by heat. These products are an acid suigeneris, which being procured from no other substance, receives from this bitumen the name of Succinic Acid ; and a peculiar empyreumatic oil. The process is conducted according to the directions given in the Pharmacopoeia. The heat requires to be raised gradually, and the interposition of the sand is useful by dividing the particles of amber, and preventing it, when it melts, from swelling up, and passing over into the receiver. The succinic acid is in part dissolved by the water which condenses in the receiver, but the greater part is condensed in the form of a crust. When purified from the adhering oil, it is obtained in minute cry stal, rhomboidal plates, of a brownish colour from a little oil still adhering to it; these are rather sparingly soluble in water, requiring 24 parts at 60° for their solution ; the taste of this acid is penetrating and slightly sour ; it reddens the vegetable colours, is soluble in alcohol, volatile and inflammable. In medicine it has been regarded as an antispasmodic and diuretic; but it appears to be wholly inactive, and is altogether discarded from practice. The oil of amber procured by the first distillation is thick, of a dark brown colour, and a very foetid smell; by successive distillations it is obtained of a thinner consistence and lighter colour, and can at length be rendered nearly limpid. Its smell still remains, however, peculiar, and ungrateful; its taste is hot and acrid ; it is volatile and inflammable, insoluble in water, and sparingly soluble in alcohol. In medical practice it has been VOLATILE OILS. 112 celebrated as a stimulant and antispasmodic, and has been given in ameuorrhosa and hysteria in a dose from ten to fifteen drops li s internal administration is, however, entirely relinquished. Externally it is sometimes applied by friction as a stimulant in paralysis, and to relieve the pain of cramp and rheumatism ; but its strong unpleasant smell renders the application extremely disagreeable. Oleum volatile pini purissimum, olim Oleum Terebinthinae purissimum. Rectified Oil of I urpentine. (Oleum Terebinthinae Rectificatum. Ph. Lond. Dub.) " Take of Oil of Turpentine, one pound ; Water, four pounds. Distil as long as an) oil passes over." The oil of turpentine of commerce is obtained by distillation from what is named Common Turpentine, the juice of the Pinus Larix, or sometimes from the wood of the tree. It appears to contain a small portion of resinous matter, as when distilled it leaves a little of a thick residuum, and the distilled oil has been said to be more volatile. The process, however, is difficult to perform, from the great volatility of the oil, and the diffusibility of its vapour; it is one too wholly superfluous, the common oil being sufficiently pure for any purpose to which it requires to be applied in medicine, and it is accordingly never attended to in the shops. The medicinal properties of this oil have been already considered. Oleum cornu cervini rectificatum. Rectified Oil of Hartshorn. Ph..Dub. (Oleum Animale. Animal Oil.) il Take of the Oil which rises in the distillation of the volatile liquor of Hartshorn, three pounds ; Water, six pounds. Distil the oil, mix it again with water, and distil it a second time ; repeat this operation frequently until it become limpid. It must be kept in small phials quite filled with it, closely stopped, and in a dark place." Animal substances submitted to heat suffer decomposition, their elements entering into new combinations, and one of the principal products of these combinations OILY PREPARATIONS. 113 is empyreumatic oil, formed from the combination of portions of the hydrogen and carbon of the animal matter. This product is obtained abundantly in the decomposition of bone or horn by heat, along with the carbonate of ammonia formed in the same process. It is at first thick, of a dark brown colour, and offensive odour: but by repeated distillations from water it is rendered thinner, more limpid, and less offensive. In this rectified state it has been celebrated as a stimulant and antispasmodic, but is discarded from modern practice. CHAPTER XVIII. OLEOSA.—OILY PREPARATIONS. The preparations included in this chapter, under this name, are combinations of expressed oils with more active substances, principally designed for external application, the oil moderating their action, or communicating a convenient form. Oleum ammoniatum, vulgo Linimentum Volatile. Ammoniated Oil f commonly called Volatile Liniment. "Take of Olive Oil, two ounces; Water of Ammonia, two drachms. Mix them." The same preparation has a place in the Dublin Pharmacopoeia, under the name Linimentum Ammoniae. In the London Pharmacopoeia, a stronger preparation is ordered, Linimentum ammonia fortius, consisting of Water of Ammonia, half an ounce; Olive Oil, two ounces. Another is inserted under the title Linimentum ammonia carbonatis, composed of Water of Carbonate of Ammonia, half an ounce; Olive Oil, three ounces, which, both from the nature and proportion of its ingredients, is milder. In these compositions the alcali combines with the expressed oil, forming a thick white saponaceous com- Vol. II. 16 OILY PREPARATIONS. 114 pound. They are all used as rubefacients, and are convenient for application ; a piece of linen moistened with any of them being applied to the part, or sometimes friction being made with the liniment for a short time. The composition of the Edinburgh College seems on the whole best adapted to general use, as of medium strength, and, if necessary, it is easy to render it a little more active. Oleum camphoratum. Camphorated Oil. Camphorae, Ph. Lond 01. Camph. Ph. Dub.) " Take of Olive Oil, two ounces; Camphor, half an ounce. Mix them, so as that the camphor may be dissolved." This is a form under which camphor is frequently applied externally as a stimulant and anodyne, and ig the most convenient one, when it is to be applied by friction. It is sometimes rendered more active by the addition of a little ammonia. Oleum sulphuratum. Sulphurated Oil. (Oleum Sulphuratum. Ph. Lond.) " Take of Olive Oil, eight ounces; Sublimed Sulphur, one ounce. Boil with a gentle fire, in a large iron pot, stirring constantly until they unite." In the London Pharmacopoeia, the proportion of sulphur is two ounces to eight of oil. This process, though apparently simple, is attended with some difficulty, the oil being very liable to boil over, or its vapour to catch fire. It is one too unnecessary, for although the composition has been recommended in catarrh, asthma, and phthysis, it has fallen altogether into disuse. It is extremely acrid and offensive. When employed, it was given in a dose from ten to thirty drops. SALTS 115 CHAPTER XIX. SALES ET SAL1NA.—0F SALTS AND SALINE SUBSTANCES. The term Salt has long been employed, in chemical language, to denote an extensive order of substances; yet it is difficult to assign to it a precise definition, or to distinguish these by characters at once sufficiently comprehensive and appropriate. It is from a combination of the following properties, however, that the definition has been attempted to be formed. Salts are said to be bodies eminently sapid, or which excite a strong penetrating taste when applied to the tongue. Many of them have indeed this power, but there are others, particularly among the earthy salts, in which any degree of sapidity is scarcely perceptible, while there are many bodies eminently sapid which are not of a saline nature. 2d. All salts are supposed soluble in water, and this, strictly speaking, is perhaps true ; but in many of them, the degree of solubility is so inconsiderable, that scarcely be assigned with propriety as a distinctive character of the order. Sulphate of barytes, for example, is not soluble in five thousand times its weight of water, and there are several others nearly equally insoluble. 3d. Salts are said to be capable of assuming a crystalline form. When dissol ved in water, many of them, on evaporation of part of the water, concrete into regular crystals. But there are others which, either from being sparingly soluble in that fluid, or from having a strong attraction to it, cannot be made to crystallize; while there are substances crystallizable even from their watery solution, sugar, for example, not saline. 4th. Salts are said to be fusible by the application of heat. But the same character may be assigned to every ether fossil substance, the pure earths excepted ; and SALTS 116 there are besides many salts, which, instead of being fused, are decomposed in a high temperature. Lastly, Salts have been considered as uninflammable ; and many of them must be so, as they are formed of substances already saturated with oxygen; but there are many others, as ammonia and the vegetable acids, as well as the compounds of these, which are more or less inflammable; some of them even burn with a bright flame. It is evident, therefore, that those properties which have been assigned as the characters of the order, are not possessed by every substance which, in chemical arrangements, is regarded as saline, but that, on the contrary, the exceptions are very numerous. Neither are they possessed exclusively by these substances ; there being bodies not saline which are sapid, soluble in water, fusible by heat, uninflammable, and which have even a tendency to assume the crystalline form. The characters of this order, therefore, are now drawn rather from the chemical composition of the substances arranged under it. It is thus understood as comprehending the acids, the alcalis, and the compounds resulting from the combination of acids with alcalis, earths, and metallic oxides. The acids and alcalis are named Simple or Frimitive Salts ; the others Secondary, or more commonly Neutral Salts, as in general the properties of the acid, and of the alcali, earth, or metal of which they are formed, are neutralized or lost. These are the substances comprised under the present chapter, with a few associated with them for convenience, though not strictly connected with them. They are, generally speaking, preparations of importance, but differing so widely in chemical constitution and medicinal powers, as to admit of no general observation. Acidum acetosum destillatum. Distilled Acetous Acid. (Acid Aceticum, Ph. Lond. —Acetum Distillatum, Ph. Dub.) " Distil eight pounds of Acetous Acid in glass vessels, with a slow fire. The two pounds that first come SALTS. 117 over are to be rejected as too watery ; the four pounds which follow are the distilled acetous acid. The residuum affords a still stronger acid, but too much burnt." The London College order the first pound only to be rejected, and the distillation to be continued until seven pounds have distilled over. The proper name of the acid thus obtained is Diluted Acetic Acid. Vinegar, Acetous acid as it is named by the College, as it is produced by fermentation, consists of acetic acid, largely diluted with water, and mixed with a number of other substances, —tartaric acid, extractive, mucilaginous, and saccharine matter. From these it is purified by distillation, but it is still largely diluted with water ; the distilled liquor is indeed even weaker than the vinegar itself, a larger portion of the acid remaining in the residual liquor ; and, in general, it receives from the distillation somewhat of an empyreumatic odour. It is usual, on the large scale, to perform the distillation in a tin still, connected with a tin spiral tube in a refrigeratory, and to add portions of boiling water during the distillation, so as to dilute the residual liquor, and bring over the whole of the acid. The process, however, ought to be conducted in glass vessels, as directed in the Pharmacopoeia ; as, from metallic ones, (tin, which has been employed, being often alloy ed with lead), the acid may receive an impregnation that might prove noxius. Distilled acetous acid is colourless, not very sour to the taste, usually slightly empyreumatic, and of a specific gravity of 1006. It is chiefly employed as a solvent of some vegetable substances, and in making some of the salts. Sometimes it is applied externally, in preference to common vinegar, as a discutient, and as an application to burns. It has the advantage, as a pharmaceutic agent, not only of greater purity, but of not being liable, like undistilled vinegar, to spontaneous decomposition. SALTS 118 Acidum acetosum forte. Strong Acetous Acid. " Take of Dried Sulphate of Iron, one pound ; Acetate of Lead, ten ounces. Rub them together Put them into a retort, and distil from sand with a moderate fire, as long as any acid comes over." Acidum aceticum. Acetic Acid. Pharm. Dub. " Take of Acetate of Potash, six ounces ; Sulphuric Acid, three ounces. Put the acid into a tubulated retort and add to it gradually, and in different portions, the acetate of potash, allowing the mixture to cool after every addition ; then distil the acid with a moderate heat until the residuum is dry. The specific gravity of this acid is to that of distilled water as 1070 to 1000." These are two processes for obtaining acetic acid in a concentrated state, and others have likewise been employed. One giving perhaps a stronger acid than either of them, has been long in use, and had a place in the former edition of the London Pharmacopoeia. It consists in exposing verdigrjs, which is a sub-acetate of copper, well dried, to a heat gradually raised, and purifying the acid which distils over by a second distillation ; the high temperature in this process merely expelling the acetic acid from the metallic salt. In the process of the Edinburgh Pharmacopoeia, the expulsion of the acetic acid from the acetate of lead is favoured by the affinity exerted to the oxide of lead by the sulphuric acid of the sulphate of iron ; and as the salts are dried, or contain little water of crystallization, the acid is supposed to be obtained in a concentrated state. In the process given by the Dublin College, the sulphuric acid combines with the potash of the acetate of potash, and disengages the acetic acid. This distils over, and as the acetate of potash contains little water, and the water of the sulphuric acid must be in part retained by the affinity exerted to it by the sulphate of potash, the acetic acid is obtained in a concentrated form. Chemists had observed some difference of properties SALTS. 119 between the acetic acid obtained from the decomposition of verdigris by heat, radical vinegar as it was named, and the acid of vinegar purified by distillation, and concentrated by freezing, or obtained in a concentrated state by the decomposition of an acetate having an alkaline or earthy base. They were therefore regarded as chemically different; the one, that obtained from themetalic salt, was believed to be more highly oxygenated, in consequence of receiving, it was supposed, oxygen from the metallic oxide, and was named Acetic Acid ; while the other, to denote its relation to this, was named Acetous Acid. At a later period, it was supposed that they differed rather in the proportion of carbon existing in their base. But the experiments, first of Adet, and since of Darracq, have proved, that they differ merely in degree of concentration, (that expelled from the metallic salt by heat being strongest,) and sometimes in a small quantity of extractive matter adhering to the acid concentrated by freezing. W hen freed from this, and when brought to the same specific gravity by diluting the stronger, they have the same properties, display the same affinities, and afford the same products by analysis. There is therefore only one acid, the Acetic, and the name Acetous is not properly applied. The process of the Edinburgh College affords an acid not so highly concentrated, and therefore not so pungent as that in which it is procured by exposing verdigris to heat. That procured by the process of the Dublin College is rather stronger ; and it has the advantage of not being liable to be contaminated by any metallic impregnation. It is also free from sulphurous acid, with a portion of which the others are sometimes impregnated. A process, which would afford it equally pure, and probably stronger, would be to decompose the solid acetate of lime by sulphuric acid, as the sulphate of lime, by its strong affinity to water, would detain it; or the acid may be brought to the highest state of concentration, by distilling it from dry muriate of lime. Acetic acid, in ite highly concentrated state, has a SALTS 120 fragrant, and, at the same time, very sharp penetrating odour; its taste is extremely sour and pungent, and it is so acrid as to inflame the skin. It is highly volatile, evaporating at the common temperature of the atmosphere; it is also inflammable when a burning body is approached to its vapour. It exerts the agencies of a powerful acid, and it has a very peculiar action on several of the proximate principles of vegetables, whence it can be applied to pharmaceutical purposes, —dissolving them, without decomposing them, or materially altering their properties. It thus dissolves resins, gum-resins, camphor, and essential oils. It is employed medicinally, principally as a stimulating perfume in langour or faintness, or to obviate the unpleasant smell of confined or corrupted air. The combination of it with camphor is principally used for this purpose, as has been noticed under the chapter of medicated vinegar, in which a preparation of this kind has a place. Acidum benzoicum. Benzoic Acid. " Take of Benzoin, twenty-four ounces ; of Carbonate of Soda, eight ounces; Water, sixteen pounds. Boil the benzoin, rubbed with the carbonate, in water for an hour, stirring them constantly, and strain. Boil the residual balsam in other six pounds of water, and strain. Mix this when strained with the former liquor, and evaporate until two pounds remain. Strain again, and drop into the liquor, as long as there is any precipitation, diluted sulphuric acid. Dissolve the precipitated benzoic acid in boiling water. Strain the liquor while hot, through linen, and put it aside, that crystals may form. These crystals being collected, and washed with cold water, dry and preserve them." The same process nearly is followed by the London College, lime being substituted for carbonate of potash, and muriatic acid for sulphuric acid. A pound and a half of benzoin are boiled with four ounces of recently prepared lime, in a gallon of water, for half an hour, stirring them constantly. This being poured off, the re- SALTS. 121 maining matter is boiled in four pints of water; the two portions are mingled together, and reduced by evaporation, to one half, and into this, when strained, muriatic acid is dropt in as long as there is any precipitation. The precipitate is dried by a gentle heat, and being put into a proper vessel, the acid is sublimed by a slow fire. The Dublin College have retained the old process of sublimation for procuring this acid. The benzoin is melted in a wide-necked retort, to which a receiver is adapted without being luted, and it is sublimed with a moderate heat. The sublimed matter condensing in the neck of the retort is removed occasionally, that it may not accumulate in two great quantity. If stained with oil, it is to be pressed, wrapped up in bibulous paper, which will absorb the oil, and is to be again sublimed. Benzoic acid exists in the various balsams, in benzoin, in largest quantity : and it is procured without difficulty, by sublimation, from the application of a moderate heat. It is this process that has been generally employed; the other methods are introduced as more economical. In the process of the Edinburgh College, the acid of the benzoin combines with the soda of the carbonate of soda, forming a soluble salt; the sulphuric acid when added, combines with the soda, and the benzoic acid, being sparingly soluble in cold water, is precipitated. The process given by the London ( ollege is essentially the same ; the benzoic acid combining with the lime, and forming a soluble salt: this cannot, however, be decomposed by sulphuric acid, as the sulphate of lime would be precipitated with the acid; muriatic acid, therefore, is added, which combines with the lime ; the mi iriate of lime remains dissolved, and the benzoic acid is thrown down. The quantity of benzoic acid obtained by sublimation is greater than can be obtained by the other methods, the product, according to Mr. Brande's experiments, amounting to two ounces from a pound of benzoin, while, according to the others, it is equal only to from one ounce five drachms, to one ounce six drachms and Vol. II. 17 SALTS 122 a half. But there is a difficulty in conducting the process by sublimation, from a portion of the oily matter of the benzoin being liable to rise with the acid in vapour, and communicating to it a brown tinge. By managing the heat, however, with due precaution, and changing the receiver towards the end of the sublimation, this may be avoided, at least so far as to obtain a pure product, nearly equal in quantity to that from the other methods ; and as the sublimed acid is more white and brilliant than the precipitated acid, even when the latter is dissolved and crystallized, this method is still usually followed by the practical chemist. The London College give the precipitated acid the same brilliant appearance by sublimation. Benzoic acid is in slender needle-like crystals, or in soft flakes, of a white colour and silky lustre; its taste is pungent and acidulous, its odour aromatic, and when it is heated, penetrating ; this odour, however, appears to arise from a minute portion of oily matter adhering to it, as by dissolving the acid in alcohol, and precipitating it by water, it is obtained nearly inodorous. It is volatile and inflammable, is scarcely sensibly soluble in cold water, but is dissolved abundantly by hot water, and is also soluble in alcohol. It has been regarded as a stimulating expectorant, but is totally destitute of medicinal efficacy, and the sole consumption of it is in the composition of the paregoric elixirs of the Pharmacopoeias, in which, as it has long been an ingredient, it is still retained. The London College have given a formula for obtaining another vegetable acid, the Citric. Acidum citricum. Citric Acid. " Take of Lemon Juice, a pint; Prepared Chalk, an ounce, or as much as may be sufficient to saturate the juice ; Diluted Sulphuric Acid, nine fluid ounces. Add the chalk to the lemon juice heated, and mix them ; then pour off the liquor. Wash the citrate of lime which re- SALTS. 123 mains with water, frequently added ; then dry it. To the dried powder add the diluted sulphuric acid ; boil for ten minutes; express the liquor strongly through linen, and strain through paper. Evaporate the strained liquor so far, that on cooling, crystals shall form. To obtain these crystals pure, dissolve them in water a second and third time ; strain the solution each time ; evaporate, and put it aside to crystallize." The juice of the lemon consists principally of citric acid, from which, however, as has been already remarked, it is difficult to abstract the mucilaginous and extractive matter, so as to render it capable of being preserved. Hence the process of obtaining the acid in a pure crystallized form, originally proposed by Scheele, has been introduced. The lime of the carbonate of lime, added to the lemon juice, combines with the citric acid, forming an insoluble precipitate, which falls down : this is washed to carry off the adhering vegetable matter, and is submitted to the action of diluted sulphuric acid: the sulphuric acid combines with the lime, and disengages the citric acid; this, dissolved by the water, is pressed out from the sulphate of lime, and by the evaporation of the solution is brought to crystallize. The crystals are at first of a brownish tinge, from the re-action, it has been supposed, of the sulphuric on the citric acid. By a second or third solution and crystallization they are obtained colourless, or rather white. A slight excess of sulphuric acid, Scheele found to be useful; and its operation, as Dize has remarked, consists in decomposing a little mucilage or extractive matter, which adheres to the citric acid, and opposes its crystallization. It remains in the residual liquor without rendering the crystals impure. Citric acid crystallizes in rhomboidal prisms; it is easily soluble in water, has a taste extremely sour, and reddens deeply the vegetable colours. In its solid state it remains unchanged, and even in solution is not very liable to spontaneous decomposition. It is used, as has already been remarked, as a refrigerant. A grateful SALTS. 124 lemonade is prepared from it, by dissolving 30 or 40 grains in a pint of water, with the addition of a little sugar, an agreeable flavour being communicated by a little dried lemon peel having been infused in the water, or a powder formed by rubbing sugar on the fresh lemon being dissolved in it. It is used, "too, in forming the common effervescing draught, being mixed with carbonate of soda, and water added. Whether it acts with equal certainty with the recent juice, as a remedy in scurvy, remains to be ascertained. Acidum muriaticum. Muriatic Acid. " Take of Muriate of Soda, two pounds; Sulphuric Acid, sixteen ounces ; Water, one pound. First expose the muriate of soda in a pot to a red heat for a short time; when cold, put it into a retort. Then pour the acid, mixed with the water, and cold, on the muriate of soda. Distil from a sand-bath with a moderate fire, as long as any acid uomes over. The specific gravity of the acid is to thai of distilled water as 1170 to 1000." The process in the other Pharmacopoeias is nearly the same, the proportions of the ingredients being different. In the Dublin Pharmacopoeia, the same weight of sulphuric acid as of muriate of soda is ordered, and the acid is diluted with an equal weight of water. In the London Pharmacopoeia, two pounds of muriate of soda are put into a retort, with a pound and a half of sulphuric acid diluted with a pint and a half of water. It wotdd require comparative experiments to determine the best proportions; but it is not improbable, that in the formula of the Edinburgh College, the proportion of acid is too small, chemists having been formerly led into error in cases similar to this, by supposing, that in decomposing a compound salt by an acid, there is no advantage in adding more of the decomposing acid than is necessary to neutralize the quantity of base which the portion of salt operated on contains, not knowing the influence of quantity in adding to the force of chemical affinity. We now know, that in every case SALTS. 125 of this kind the product is increased by employing more of the decomposing agent than is-strictly necessary to neutralize the ingredient with which it combines; and that if this excess be not employed, a portion of the compound operated on is not decomposed. 1 have accordingly observed, in performing the above process, according to the formula of the Edinburgh College, that a portion of undecomposed muriate of soda exists in the residual mass. The cake remaining in the retort is easily dissolved by pouring water on it when the retort is perfectly cold, and its solution is favoured by the excess of acid in its composition. The London College direct that the sulphuric acid be diluted only with a portion of the water, and that the remaining water be put into the receiver. This is proper, both as abridging; the distillation, and assisting the condensation of the acid gas. An apparatus on the construction of Woolfe's, is sometimes employed, but is unnecessary, as a range of two or hree receivers, without tubes immersed in the liquid in each, is sufficient. The advantage of diluting the acid with at least a portion of the water, is, that the rapid effervescence and disengagement of gas produced by the action of the concentrated acid on the muriate of soda is prevented, and the process is rendered more manageable. In the large way the distillation is sometimes performed from an iron pot connected by an earthen head and tube with a range of receivers, the fire being directly applied, and then the concentrated sulphuric acid is poured directly on the muriate of soda to lessen the action on the iron. But the acid prepared in this way, even when the precaution is followed, of coating the inner surface of the pot, is always contaminated with this metal. The yellow colour which the acid usually has, is not always, however, owing; to the presence of iron, but is derived sometimes from t a little extractive matter adhering to the sea salt, and it is to consume this that the salt is ordered, in the Edinburgh Pharmacopoeia, to be exposed to a red heat. The yellow colour may be removed, by 126 SALTS. distilling the acid a second time from a little muriate of soda. To the test of the strength of the acid from its specific gravity, the London College have added, that a fluid ounce of it, diluted with water, ought to dissolve, of a pure limestone, half an ounce. The theory of the process is sufficiently simple In all cases, where two acids act on one base, this base would be shared between them, in proportions determined by their affinities to it, and their relative quantities. But circumstances may prevent this participation, and cause one of the acids alone to combine with the base, as, for example, the application of a certain temperature, when one of the acids is much more disposed than the other, to assume the elastic form. This happens in the present case. The sulphuric acid exerts an affinity to the soda of the muriate of soda ; this weakens the affinity exerted by the soda to the muriatic acid ; its tendency to assume the elastic form prevails and a portion of it is disengaged, and by the application of heat aided by the quantity of sulphuric acid employed, the decomposition is rendered complete,—or the sulphuric acid combines with the soda, and the muriatic is disengaged ; it is condensed partly by the water which rises with it in vapour, and partly by the water placed in the receivers. Muriatic acid exists when uncombined in the elastic form, and is incapable of condensation by any cold or pressure hitherto applied to it. But it is rapidly and largely absorbed by water; the water, at a common temperature, and under a mean pressure, condensing *60 times its volume. When of the strength stated in the Pharmacopoeias, the specific gravity of 1.170, it is supposed to contain %% of real acid, and 78 of water ; it emits pungent vapours of muriatic acid gas on exposure to the air reddens deeply the vegetable colours, tastes extremely sour, erodes even immediately vegetable and animal substances, and exerts considerable chemical agencies. The acid, however, not yielding oxygen readily, can oxidate inflammable and metallic substances, only by enabling SALTS 127 them, by a resulting affinity, to attract oxygen from the water with which it is combined. The decomposition of this acid has been hitherto only imperfectly effected. Galvanism can scarcely be brought to act on it in the elastic form ; and in the liquid state the water only is decomposed. By heating potassium in the gas, rendered as dry as possible, hydrogen is evolved, and in such quantity as to prove that the acid gas retains a very large quantity of water combined with it; and more lately Mr. Davy has discovered, than when the acid is obtained in free, or nearly so, from this water, its acidity is suspended, but is immediately restored on the addition of water ; —facts yvhich, in the present state of chemical theory, admit of no satisfactory explanation. Muriatic acid is applied to no medicinal purpose. It has a place in the Pharmacopoeias, merely as being employed in various pharmaceutic processes. Acidum mvriaticum dilutum. Diluted Muriatic Acid. Ph. Dub. M Take of Muriatic Acid, Distilled Water, each one pound. Mix them." This is a formula wholly superfluous, as muriatic acid is not employed medicinally, and requires therefore no adjustment to render its exhibition convenient; and for any pharmaceutic process, it is easy to order its dilution to the requisite extent. Acidum oxymuriaticum. Oxymuriatic Acid. When muriatic acid is distilled from substances capable of affording oxygen easily, k is converted into a species of elastic fluid altogether different in its chemical properties, which is considered as a compound of muriatic acid with oxygen, and is therefore named Oxymuriatic acid. This has been applied to some medicinal purposes, and a process for preparing it has been introduced into the Dublin Pharmacopoeia The compound salt which is formed when this acid is presented to potash, the Oxymuriate of Potash, has also received SALTS. 128 a place in the Materia Medica ; and the process may be conducted so that it aUo shall be obtained. The preparations in which the oxy muriatic acid is formed, in the process given by the Dublin College, have been named Aq.ua axymuriatico et aq.ua alkalina oxymuriatica. "Take of Muriate of Soda, dried, two pounds ; Manganese in powder, one pound; Water, Sulphuric Acid, each two pounds. Mix the muriate of soda and the manganese ; put them into a matrass, and add the water; then by a convenient apparatus add the sulphuric acid gradually and at intervals ; transmit the gas which is disengaged through a solution of four ounces of subcarbonate of potash, in twenty-nine ounces of water. Toward the end of the operation, apply a moderate heat to the matrass. The specific gravity of this liquid is to the specific gravity of distilled water as 1087 to 1000." " The Oxy muriatic Water (or solution of oxy muriatic acid in water) is prepared by transmitting the superfluous gas of the above process, by a proper apparatus, through a pint of distilled water. The specific gravity of this liquor is to that of distilled water as 1003 to 1000." When muriate of soda, black oxide of manganese, and sulphuric acid are mingled together, the sulphuric arid combining with the soda disengages the muriatic acid ; and the acid, receiving oxygen from the oxide of manganese, is converted into oxymuriatic acid, which assumes the elastic form. If the sulphuric acid is concentrated, its action is rather too rapid, and gives rise to a disengagement of gas not easily regulated; and if any part of the elastic product is forced from the apparatus, it is extremely disagreeable to the operator, from its highly suffocating odour. It is pcoper therefore to use the acid diluted somewhat, and alter the commencement of the operation, to favour its progress by the application of a moderate heat. The proportions of the ingredients recommended by Vauquelin, are four parts of SALTS. 129 muriate of soda, one of oxide of manganese, three of sulphuric acid, and two of water. When the combination of the gas, either with water, or with an alkaline solution, is to be effected, it is proper to use the bottles of Woolfe, so as to transmit the gas through the liquid, the first bottle being left empty to collect a little common muriatic acid that distils over, holding oxide of manganese dissolved. Oxymuriatic acid has been employed to neutralize the agency of contagion, and change the noxious constitution of foul or corrupted air. To Guy ton we are indebted for this application of it. It has been successfully applied in fumigating the wards of hospitals, the apartments of a prison, or other situations in which the atmosphere is contaminated by noxious effluvia, and probably is in this respect the most powerful agent we have it in our power to employ. By its chemical agency, it changes the constitution of the greater number of the compound gases, and more particularly of those having carbon and hydrogen as their elements. Noxious effluvia, derived from the decomposition of vegetable and animal matter, which are the usual sources of a corrupted or contagious atmosphere, may be presumed to be of similar constitution, and therefore to be liable to similar decomposition ; and accordingly it has been ascertained, that air highly tainted has its purity, so far as is connected with the removal of such effluvia, restored by the diffusion of the vapours of oxymuriatic acid. The usual materials are mingled together, the sulphuric acid being used in its concentrated state, and are distributed in different vessels placed in the apartment designed to be fumigated. The only disadvantage attending the use of it is, that from its suffocating odour, the atmosphere in which it is diffused cannot be breathed; and in some situations, as in hospitals, where the sick cannot be removed, this renders it necessary to substitute the nitrous acid vapour. But where this does not limit its use, the oxymuriatic acid, as more active, is to be preferred. In its pure state, the oxymuriatic acid is not applied to Vol. II. 18 130 SALTS any other medicinal use, and there is therefore scarcely any necessity for the solution of it in water, which has received a place in the Dublin Pharmacopoeia. The salt obtained by transmitting the oxymuriatic acid gas through a solution of potash, and named the Oxymuriate oi Potash, it has already been remarked, has been received into the Materia Medica, and has been employed as an antisyphilitic remedy. This salt is not strictly an oxymuriate, but the compound of an acid containing still more oxygen than the oxymuriatic acid, what has been named the Hyper-oxymuriatic Acid. When the oxymuriatic acid gas is introduced into the alkaline solution sufficiently concentrated, it undergoes a singular decomposition: one portion of it returns to the state of muriatic acid, and combines with part of the alkaline base; the other portion, receiving the oxygen which this had parted with, passes to the state of an acid, having of course a still larger portion of oxygen in its composition than the oxymuriatic acid, and this combines with another portion of the alkali. The former salt, the muriate of potash, being abundantly soluble, remains dissolved; the other, being more sparingly soluble, is deposited in crystalline plates. These form the salt properly named Hyper-oxymuriate of Potash, (Hyperoxy murias Potassae.) These combinations are much influenced by the concentration of the alkaline solution. If it is much diluted, the oxymuriatic acid is absorbed by it, and remains united with the water and the alkali w ithout decomposition ; as is evident from the liquor retaining the property of destroying the vegetable colours, —a property belonging to the oxymuriatic acid, but not to the hyperoxymuriate of potash. It is only when the more powerful action of the alkali on the acid is favoured by concentration, that the decomposition takes place ; and Bevthollet has supposed, even, that it is much determined by the operation of crystallization itself. The alkaline solution, therefore, into which the oxymuriatic acid gas is transmitted, ought to be of such a strength. SALTS. 131 that the hyper-oxymuriate will be formed in it, and crystallize spontaneously; The solution ordered by the Dublin College appears to be too weak, and the liquor obtained by their process probably contains much of the oxymuriatic acid undecomposed. A solution of the proper strength is obtained by dissolving sixteen ounces of sub-carbonate of potash in four pounds of water; and as the disengagement of the carbonic acid, by the action of the oxymuriatic acid, is troublesome, it is better to remove it by previous agitation of the solution with eight ounces of lime. From this solution, when the transmission of the oxymuriatic acid gas is continued for a sufficient length of time, the hyper-oxymuriate crystallizes spontaneous!), and the quantity of crystallized salt ought not to be increased by any evaporation of the liquor, as a portion of muriate of potash might crystallize along with it. The crystals are therefore removed, washed with a little cold water, and dried. And when the salt is to be medicinally use d, it ought always to be under this crystallized form. The solution ordered in the Dublin Pharmacopoeia must be an uncertain preparation. Hyper-oxymuriate of potash crystallizes in thin quadrangular tables, white, with considerable lustre. Its taste is cool and penetrating. It dissolves in seventeen parts of cold water and in five of boiling water ; is fused by heat; and by a higher heat is decomposed, giving out very pure ygen gas. From the facility with which it parts with oxygen, it acts with much force on ble bodies, producing, by mere trituration with them, or percussion, violent deflagrations or detonations. Its medicinal applications have been already pointed out. When nitric acid was introduced as a remedy in syphilis, the theory which suggested its use led likewise to the employment of hyper-oxymuriate of potash. It w as given in a dose of ten grains thrice a day; and from the case s then brought forward, appeared to be superior even to nitric acid in suspending tiie symptoms of syphilis. It was not however ultimately established in 132 SALTS. practice, and as no great advantage appears to be derived from it as an auxiliary to mercury, it as now seldom prescribed. Acidum nitrosum. Nitrous Acid. Ph. Ed. Dub. " Take of Nitrate of Potash bruised, two pounds; Sulphuric Acid, sixteen ounces. The nitrate of potash being put into a glass retort, pour upon it the sulphuric acid, and distil from a sand-bath with a fire gradually raised, until the iron pot is at an obscure red heat. The specific gravity of this acid is to that of distilled water as 1550 to 1000." The directions in the Dublin Pharmacopoeia are nearly the same. In this process the sulphuric acid combines with the potash, and disengages the nitric acid. The latter acid, however, principally from the agency of the heat, especially towards the end of the distillation when it is necessary to raise it pretty high, suffers a partial decomposition ; a small portion of it loses a part of its oxygen, and a quantity of nitric oxide gas is formed; this is absorbed by the nitric acid, and forms the nitrous acid, which is of a yellow or red colour, and fuming, more or less so, according as it is more largely impregnated with nitric oxide, and, according, therefore, to the degree of heat employed in the distillation. The residuum is sulphate of potash, with an excess of sulphuric acid, this excess of acid being necessary to render the decomposition of the nitre complete. The specific gravity of the acid is probably stated too high ; the coloured, or what is strictly named Nitrous Acid, being not easily procured of a greater specific gravity than 1.52. It sometimes contains a minute quantity of sulphuric acid and muriatic acid ; the first is detected by adding muriate of barytes to the acid diluted with two parts of distilled water, sulphate of barytes being formed ; the other is detected by nitrate of silver, muriate of silver being precipitated. "When not intentionally added, however, these acids are never present in sufficient quantity to render it unfit fox medicinal or pharmaceutical use. SALTS 133 Nitrous acid is extensively employed as a pharmaceutic agent: from the facility with which it parts with oxygen, it is one of the most important, particularly in oxidating and dissolving the metals. Its powers as a tonic and antisyphilitic remedy have been already considered ; and indeed, when internally administered, it is necessarily given in the state of nitric acid, being brought to this state by dilution with water. In the state of vapour, it has been employed under the form of fumigation to destroy contagion ; the due proportion of nitre and sulphuric acid being mingled together in small earthen cups, which are put in warm sand, and placed in the apartment designed to be fumigated, and though inferior to oxymuriatic acid in power, it has the advantage that it can be applied without requiring the removal of the sick. Acidum nitrosum dilutum. Diluted Nitrous Acid " Take of Nitrous Acid, Water, equal weights. Mix them, avoiding the noxious vapours." In combining nitrous acid with water, the greater pait of the nitric oxide gas, if it is highly charged with it, is disengaged with effervescence; if less is present, it is retained and converted into nitric acid by the oxygen held loosely dissolved by the water. The diluted acid is employed in a number of the chemical processes of the Pharmacopoeia, and is convenient, in particular, for the solution of metals, being of that strength at which its action upon them is not too rapid. Acidum nitricum. Nitric Acid. Ph. Ed. " Take of Nitrous Acid, any quantity. Put it into a retort, and a receiver being adapted, apply a very gentle heat until the reddest part shall have passed over, and the acid which remains in the retort shall have become nitric acid." The heat is best applied by the medium of a water-bath. Another process has been given in the London Pharmacopoeia for the preparation of nitric acid. SALTS. 134 " Take of Nitrate of Potash dried, Sulphuric Acid, each two pounds. Mix them in a glass retort; then distil the nitric acid with the heat of a sand-bath, until red vapours are produced. Lastly, having poured the distilled acid on an ounce of dried nitrate ot potash, distil it again in a similar manner. The specific gravity of nitric acid is to that of distilled water as 1500 to 1000. If a piece of limestone be put into a fluid ounce of it diluted with water, seven drachms ought to be dissolved." The process given in the Edinburgh Pharmacopoeia is that which has been usually followed by chemists to convert nitrous into nitric acid. The nitrous acid is merely the nitric holding dissolved a portion of nitric oxide : when heat is applied, the nitric oxide being more disposed than the acid to assume the elastic form, the affinity by which it is retained in combination with it is weakened, and it is disengaged : this affinity, however, so far continues to operate, that it carries a portion of the-acid along with it, and it escapes therefore in the state of very deep coloured nitrous acid vapour. The process is thus so far attended with loss, but this is easily obviated by condensing the nitrous acid vapour, by a portion of water put in the receiver, the diluted acid which will thus be obtained being easily applied to use. The heat ought to be applied by a water-bath, this being sufficiently high to expel the nitric oxide gas, and being not too high to produce decomposition of the acid. It is difficult, however, by this method, to render the acid perfectly colourless, the last portion of nitric oxide, communicating a pale straw colour, being retained by such an affinity, and the volatility of the acid in this state approaching so nearly to that of nitric acid, that the whole may be distilled without the oxide being entirely separated. A more perfect process to obtain perfectly colourless nitric acid, is to distil it from a little black oxide of manganese, whicn yields oxygen to the nitric oxide. SALTS. 135 in the process of the London Pharmacopoeia, from the large quantity of sulphuric acid employed to decompose the nitre, the acid is obtained by the first distilla tion nearly in the state of nitric. The operation of this exc ess of sulphuric acid, in preventing the partial decomposition which would form nitrous acid, probably depends on two circumstances: one, that from the quantity adding to the force of its affinity, less heat is required to promote the decomposition of the nitre, and the greater part of the nitric acid is thus brought over before it is necessary, in continuing the distillation, to raise the temperature so high as to evolve nitric oxide ; the other, that the water of this excess of acid will be volatalized, in the progress of the distillation, and contribute to preserve the constitution of the nitric acid. The influence of the latter circumstance is very well shown by the fact, that the product, instead of being superior in specific gravity to nitrous acid, as concentrated nitric acid is, is inferior, being, as stated in a report made to the College on the products of this process from different proportions of the materials, 1.50, while the nitrous is stated as having been obtained at 1.53. The weight too of the former, from a given quantity of nitre, amounted to four, that of the latter only to three. The relative value of the two is expressed by the quantity of marble they dissolve, that of the nitrous being stated at twenty - one, that of the nitric twenty-nine, expressing probably, (for they are not stated in a very distinct manner), not the relative strengths of equal weights of the two, but the relative strengths of the entire products, from a given weight of nitre. It thus will follow, that though a larger quantity of acid is obtained from the materials, by the mode of conducting the process in the London Pharmacopoeia, the acid itself is not in its concentrated state. Nitric acid is applied to the same purposes as nitrous acid. Medicinally, they must be the same, as the nitrous, by the dilution necessary for its administration, is converted into the nitric. And in their chemical agencies, and therefore in their pharmaceutic applications, they are precisely alike. SALTS 136 Acidum sulphuricum dilutum. Diluted Sulphuric Acid. Ph. Ed. Lond. Dub. " Take of Sulphuric Acid, one part; Water, seven parts. Mix them." . The same proportions are given in the Dublin Pharmacopoeia. The London College have, without any necessity, altered the proportions both from those of the other Pharmacopoeias, and from those which had formerly been ordered in their own Pharmacopoeia ; they order a fluid ounce and a half of sulphuric acid to be mixed with fourteen fluid ounces and a half of distilled water, giving the proportion by weight of one part of acid, to nearly five and a half of water. The reason given for this change is, that " the mixture will be more conveniently made, and its dose more easily apportioned, than that of the former Pharmacopoeia." The absurdity of this is obvious. A mixture of sulphuric acid with water is made just as easily in one proportion as in another, and the dose of the diluted acid, whatever may be its strength, is apportioned with equal facility. Nor is it of any importance to have any relation between the dose of the diluted acid and any particular quantity of the concentrated acid, as the acid in the latter state has never been prescribed internally. It is to be regretted, that the strength of a preparation, to which practitioners have long been accustomed, has been thus unnecessarily changed. The preparation of Sulphuric Acid being carried on on a large scale, for the purposes of commerce, no process is given for it in any of the Pharmacopoeias, nor could it be executed in the shops. It is formed by burning sulphur mixed with from one-eighth to one-tenth of nitrate of potash, in large leaden chambers. By the oxygen afforded by the nitre, the sulphur is enabled to burn slowly, though the chamber be closed so as to admit of a very imperfect circulation of air; and the acid formed is principally the sulphuric, while from the combustion of sulphur in atmospheric air alone, sulphurous acid chiefly is produced. The acid vapours are absorbed by water placed in the bottom of the chamber. This liquor SALTS, 137 when sufficiently acidulated, is concentrated by evaporation, and*afterwards by boiling it in glass retorts, and an acid is obtained thick and oily in its appearance, colourless and transparent, having a specific gravity of 1850. Formerly this acid was procured from the decomposition of sulphate of iron, the green vitriol of commerce, by heat; and hence the origin of the name, Vitriolic Acid, by which it has been known. Sulphuric acid prepared in this manner is never perfectly pure. It contains a quantity of sulphate of potash, (the acid combining with a portion of the potash of the nitre,) and sometimes a small portion of sulphate of lead, derived from the action of the acid on the lead of the chamber. From these it is in a great measure purified by dilution with water, the diluted acid being incapable of holding them dissolved, and hence one advantage of the dilution. The dose of the diluted is also more manageable than that of the concentrated acid. As an astringent it is taken to the extent of from fifteen to thirty drops, usually in a cupful of water. Acidum Sulphuricum aromaticum. Aromatic Sulphuric Acid. u Take of Alcohol, two pounds; Sulphuric acid, six ounces. Drop the acid gradually into the alcohol. Digest the mixture with a very gentle heat in a close vessel for three days, then add of Bark of Cinnamon bruised, one ounce and a half; of Ginger bruised, one ounce. Digest again in a close vessel for six days; then strain through paper placed in a glass funnel" The dilution of the acid by the alcohol is in the proportions in which they are mixed in this preparation, such, that little chemical action appears to be exerted during the digestion; an odour somewhat peculiar is acquired, but the acidity is little impaired. The aromatics render it more pleasant, and the preparation may be considered therefore as a grateful one for the exhibition of sulphuric acid. Its dose is thirty drops, given in a oupful of water. It is not unfrequeatly ased in dyspepsia Vol. II. 19 SALTS. 138 haemoptysis, and other diseases in which this acid is employed. iETHER sulphuricus. Sulphuric Ether. " Take of Sulphuric Acid, Alcohol, of each thirtytwo ounces. Pour the alcohol into a glass retort, capable of bearing a sudden heat. Then pour on the acid in an uninterrupted stream. Mix them gradually by frequent and gentle agitation ; then immediately distil from a sand-bath, previously heated for this purpose, into a receiver kept cool with water-or snow. Let the heat be regulated in such a manner that the liquor may be made to boil as soon as possible, and continue to boil until sixteen ounces have distilled over; then remove the' retort from the sand. To the distilled liquor add two drachms or potash ; then distil again from a high-necked retort, with a very gentle heat, into a receiver kept cool, until ten ounces have passed over. If to the acid remaining in the retort after the first distillation, sixteen ounces of alcohol be added, and the distillation be repeated, ether will again be produced. And this may be often repeated." The directions in the other Pharmacopoeias, for conducting this process, are nearly the same. In the London Pharmacopoeia, the acid is ordered to be added gradually to the spirit, agitating the mixture after each addition; but on account of the rise of temperature as the mixture proceeds, this mode is more difficult than that directed by the Edinburgh College, of mixing the whole "acid and alcohol at once, and any loss of ethereal vapour from the sudden action produced by the mixture is very trivial. The direction given by the Dublin College, to heat the spirit to 120°, before adding the acid, must render the making the mixture more difficult and endanger the breaking of the retort from the addition of the dense cold acid. On mixing equal weights of sulphuric acid and alcohol, a mutual action, marked by an elevation ot temperature, and a hissing noise is produced, and a vapour is SALTS 139 disengaged, of a pleasant ethereal smell. On raising the temperature by the application of heat, so as to cause the mixed liquor to boil, ether is formed, and distils over. This continues for a considerable time: towards the end of this stage of the process, the liquid in the retort is capable of sustaining a higher temperature, and along with the ether, there is produced a white vapour, which condenses in streaks having an oily appearance, in the neck of the retort, and this increasing, collects in the form of a dense oily-like fluid, named Oil of Wine, or Ethereal Oil, which falls to the bottom of the receiver. If the heat be continued beyond this, there is a sudden and copious production of sulphurous acid gas, which, not escaping easily from the heavy liquor in the retort, causes it to swell up, and if not removed from the fire, it will pass over into the receiver. The principle nicety, therefore, in conducting the process, is to continue the distillation, so as to obtain the largest produce of ether, without bringing over the liquor from the retort. The rule given in the Edinburgh Pharmacopoeia is to continue it, until the liquid condensed in the receiver is equal to half the quantity of alcohol that had been employed ; as when this has been obtained, the formation of ether will have nearly ceased. The London College direct the distillation to be continued until the ethereal oil is produced ; and if care be taken to guard against the sudden swelling up of the liquor in the retort, this may be done, and rather a larger product obtained. Whenever the neck of the retort becomes obscured with white vapours, the fire should be withdrawn; and if the materials begin to swell, the retort ought to be raised in the sand. The receiver requires to be kept cool by immersion in water, or causing water to trickle over it, in order to promote the condensation of the ether; and care ought to be taken to avoid approaching a burning body to the apparatus as accidents have sometimes happened, when the vessels were not closely luted, from the volatility and inflammability of the ethereal vapour. 140 SALTS", There is considerable difficulty in establishing the theory of the formation of ether. As the process proceeds, the liquor in the retort assumes a dark colour, and a quantity of carbonaceous matter, somewhat bituminous, is diffused through it; it is likewise found to be considerably diluted with water, and another portion of water distils over with the ether. These changes, and the formation of the ether, must be referred to changes in the composition of the alcohol; and they were generally supposed to be owing to a portion of oxygen from the acid, being communicated to the hydrogen of the aiohol, and forming water; the balance of affinities being thus broken, part of the carbonaceous matter of the alcohol is likewise separated, and its remaining hydrogen and carbon, with any portion of oxygen it may contain, entering into combination, form the ether. To this theory however, it was some years ago objected by Fourcroy and Vauquelin, that the decomposition of the sulphuric acid is not essential to the formation of ether: it may take place to a certain extent towards the end of the process, when the temperature is high, and the liquor is loaded with carbonaceous matter; but there are no indications of it, they affirm, in the earlier stage, during which principally ether is formed : there is no evolution of sulphurous acid, and if the process be stopt at this stage, it is affirmed by these chemists, that the whole acid is to be found undecomposed, the residual liquid being capable of saturating as much of an alkaline base, as the quantity of sulphuric acid employed would do. They gave, therefore, a different view of the agency of the acid. Instead of communicating oxygen, tbey suppose it to operate by a disposing, or what would now be named a resulting affinity, causing part of the oxygen and hydrogen of the alcohol to combine and form water; then the equilibrium of affinities being subverted, carbonaceous matter is precipitated from the alcohol, and the new affinities being exerted, ether is the product of the combination of its remaining elements. The subject, however, notwithstanding the researches of SALTS. 141 these chemists, is obscure. The fact, with regard to the acid not being decomposed, is not altogether certain; for the non-appearance of sulphurous acid, from winch it has been inferred, may be owing to the small quantity evolved combining with the ether; and the power of the liquid to saturate as much of an alkaline base, as the sulphuric acid used in the process could do, may, if any portion of the acid be decomposed, be owing to the formation, by a partial oxygenation of the elements of the alcohol, of acetic or oxalic acid, both of which have been said to exist in the residual liquor. The facts, that those acids form ethers most readily from alcohol, which yield oxygen most readily, and that those which cannot communicate it directly form it with difficulty, and only by arrangements by which oxygen is communicated from some other substance, favour the supposition, that a communication of oxygen from the acid is necessary to the commencement at least of the series of changes. It is sufficiently proved, however, that the decomposition of the acid is not necessary to any great extent, for the residual liquor is still capable of converting a fresh portion of alcohol into either, and as this is economical, it is ordered in the Pharmacopoeias. And its power of doing so appears to diminish progressively, not so much from exhaustion of the acid, as from its becoming too much diluted with water. This water may have either entirely pre-existed in the alcohol; or only partially, and have been in part formed by combination of portions of oxygen and hydrogen ; and we have no certain mode of determining which of these is the case. The carbonaceous matter which is precipitated, is obviously derived from the alcohol; and its separation led to the eonclution, that less of this matter must exist in the composition of ether that in than of alcohol; that hydrogen, therefore, predominates in the composition of the former, and to this its greater volatility and levity were ascribed. Both alcohol and ether in burning afford water and carbonic acid, and from the eomparative quantities afforded SALTS 142 in the combustion of each, Cruickshank inferred that the proportion of carbon to hydrogen is in ether as 5 to 1 nearly, while in alcohol it is as 8 or 9 to 1. The younger Saussure has more lately endeavoured, from the products of their detonation with oxygen, to discover their composition, and ether, he supposes, to contain more carbon and hydrogen than alcohol, but less oxygen. He states its composition at 59 carbon, 22 hydrogen, and 19 oxygen. Ether obtained by the first distillation is not pure. It is diluted with a considerable proportion of water, sometimes also it contains alcohol, and very generally a portion of sulphurous acid, which had been evolved towards the end of the distillation. To free it from these is the object of the directions for its rectification inserted in the formula of the Pharmacopoeia,—the sixteen ounces of liquid first procured being distilled from two drachms of potash, from a high necked retort, with a very gentle heat, until ten ounces are obtained ; the potash detaining the sulphurous acid by the affinity it exerts to it, and rendering the water also less volatile. The same directions are given in the other Pharmacopoeia, a portion of water only being ordered to be added to the potash and ether in the London Pharmacopoeia, which may be useful by attracting the alcohol more effecually. If the ether of the first distillation be much impregnated with sulphurous acid, from the distillation having been continued longer than usual, it will be useful in the process of rectification to add a little black oxide of manganese, which yielding oxygen to the sulphurous acid, converts it into sulphuric, and abstracts it more effectually than is done by the alkali alone. In the London and Dublin Pharmacopoeias, both the Unrectified and Rectified Ether have a place, the Ether, as obtained by the first distillation, being named iEther Sulphuricus in the London Pharmacopoeia, and Liquor iEthereus Sulphuricus in the Dublin; and when rectified, iEther Rectificatus in the former, iEther Sulphuricus in the latter. The Edinburgh College, with more propriety, admit of SALTS 143 no distinction, but name the product when rectified, Sulphuric Ether, and sanction its use only in this state. Sulphuric Ether in a state of purity has a peculiar odour, strong and diffusive, but not pungent; its taste is warm and penetrating ; it is colourless and transparent; its specific gravity is 0.732, and when highly rectified is brought so low as .716; it is therefore one of the lightest known liquids. It is also one of the most volatile ; it evaporates rapidly at common temperatures; it boils strongly in vacuo, even below 32, and under the atmospheric pressure at 98 Q . In evaporating it absorbs much caloric; hence, if dropt on the hand it quickly disappears, producing on the spot a sensation of cold: and this affords a very good test of its purity, the volatility being greater, as it is more highly rectified. It is soluble in alcohol in every proportion ; in water only in the limited proportion of one part to ten ; and this affords another test of its proper preparation, as if more soluble it is diluted either with water or alcohol. Its medicinal properties have been already considered. It is employed principally as an antispasmodic, being given in a dose from half a drachm to a drachm. And it is sometimes applied externally as a stimulant, or, from the cold attending its evaporation, as a remedy to burns. jEther sulphuricus cum alkohole. Sulphuric Ether with Alcohol. (Spiritus iEtheris Sulphurici, Ph. Lond.) " Take of Sulphuric Ether, one part; Alcohol, two parts. Mix them together." A process had formerly a place in the Pharmacopoeias, in which sulphuric acid and alcohol were submitted to distillation, more alcohol being employed than the acid could convert into ether. A portion of it, therefore, distilled over unchanged on the first application of the heat, and served merely to dilute the ether that followed. For this preparation which had been received into practice under the name of the Sweet Spirit of Vitriol, the present has been substituted, but it has no peculiar advantage, and is seldom prescribed. 144 SALTS. .Ether sulphuricus cum alkaholb aromaticus. Aromatic Sul- phuric Ether with Alcohol. (Spiritus iEtheris Aromaticus, Ph. Lond. ) " This is made from the same aromatics, and in the same manner as the Compound Tincture of Cinnamon, unless that in place of Diluted Alcohol, Sulphuric Ether with alcohol, is employed." The addition of these aromatics to the sulphuric Ether in this formula is of so little importance, that the preparation is scarcely ever used. To the preceding preparations, the London and Dublin Colleges have added another, —the peculiar oily-like fluid which is produced in the latter stage of the process for forming Ether, the Oil of Wine, as it used to be named. Oleum jEthereum. .Ethereal Oil. Ph. Lond. " The liquor remaining after the distillation of sulphuric ether, distil with a very gentle heat, until a black froth swells up ; then immediately remove the retort from the fire. To the liquor which remains in the retort, add water, so that the oily part may float upon it. Draw this off, and mix with it lime-water, as much as may be sufficient to neutralize the acid mixed with it. Lastly, withdraw the etherial oil after it has separated." A different process is given by the Dublin College to obtain a similar product, which they name Liq_uor .ethereu8 oleosus. Oily Ethereal Liquor. " Take the liquor remaining in the retort after the distillation of sulphuric ether. Distil it with a moderate heat to one half." The product obtained by these processes is probably the same, being formed in the first process, but not distilled over; in the second, being obtained insulated by distillation, though to conduct this is attended with considerable difficulty, from the re-action of the carbonaceous matter which has been separated from the alcohol, <*n the sulphuric acid. The nature of this oily substance SALTS 145 has not been well determined. It has been considered as a compound of ether and sulphurous acid, but no proof is given that by the combination of these it can be formed. Fourcroy and Vauquelin have supposed, that it is analogous to ether, differing from it in containing a larger proportion of carbon. It can be formed more directly by distilling ether from sulphric acid. It is thick, unctuous in appearance, less volatile than ether, and soluble both in it and in alcohol. It is applied directly to no medicinal use, but is employed in forming the following preparation: Spiritus compositus. Compound Spirit of Ether. Ph. Lond. " Take of Spirit of Sulphuric Ether, a pint; Ethereal Oil, two fluid drachms. Mix them." A composition had been in use under the name of Hoffman's Anodyne Liquor, which consisted of alcohol, with a portion of ether and ethereal oil. This, after having been discarded from the Pharmacopoeias, has been restored in the present preparation, on the supposition that it possesses superior pov\ ers as an anodyne. It probably differs, however, in nothing from ether with alcohol, at least there is no distinct proof of any peculiarity of operation being communicated by the ethereal oil. .Ether nitrosus. Nitrous Ether. Ph. Dub. " Take of Nitrate of Potash, dried and in coarse powder, one pound and a half; Sulphuric Acid, one pound ; Rectified Spirit, nineteen ounces by measure. Put the nitrate of potash into a tubulated retort, placed in a bath of cold water; and add to it gradually, and in small quan< tities, the sulphuric acid and alcohol, previously mixed and allowed to become cold. Without the aid of any external heat, or with only such a slight degree of it as may be communicated by the addition of a little tepid water to the bath, an ethereal liquor will begin to distil In a short time, the heat of the retort will increase spontaneously, and a considerable ebullition w ill take place. Vol. II. 20 146 SALTS. which must be moderated by adding a portion of cold water to the bath. The receiver ought also to be kept cold with water or snow, and it ought to be furnished with an aparatus adapted to transmit through a pound of rectified spirit, in a phial kept cold, the highly elastic vapour disengaged suddenly, and with great force, from the mixture, when the heat is raised rather too high. The ethereal liquor thus obtained by spontaneous distillation is to be put into a phial closely stopt with a glass stopper: and to neutralize the excess of acid, as much sub-carbonate of potash in dry powder is to be added as is necessary, closing the phial after each addition, and determining the neutralization by the test of litmus. This is generallv attained on the addition of about a drachm of the salt, and in a short time the ni ] trous ether rises to the surface, and may be withdrawn by a funnel. To obtain the ether in its purest state, distil it from a water-bath, heated to about 140 degrees, to one half. Its specific gravity is to that of distilled water as 900 to 1000." The process for preparing nitrous ether has always been found extremely difficult, from the great susceptibility of decomposition of the acid, and the rapidity with which it communicates oxygen to the alcohol. Their mutual action, in consequence of this, becomes extremely violent, and it is difficult to add the requisite proportion of nitric acid to convert it into ether, or to do so at least without considerable waste in the dissipation of elastic products. Different arrangements have been contrived to facilitate this, but probably none that can he conducted more easily than that now received into the Dublin Pharmacopoeia, originally contrived by Woolfe, and found by Pelletier to succeed better than any other. The addition of the mixture of sulphuric acid and alcohol should be made in small quantities at a time, not exceeding two ounces, and the quantity of product is increased by keeping the first receiver perfectly cool, and connecting with it not merely one bottle, but a range of bottles, containing, according to a SALTS. 147 method employed by Thenard, a saturated solution of muriate of soda kept cold by ice, through which the elastic product is transmitted ; it is condensed, and the liquid floats on the surface. The theory of the formation of nitric ether remains obscure ; the series of changes, however, are obviously altogether different from those which take place in the production of sulphuric ether. The acid is entirely decomposed, or nearly so, scarcely any trace of it having been found by Pelletier in either the distilled or the residual liquor ; there is no precipitation of carbonaceous matter from the alcohol, the liquor remaining transparent, and of a light yellow colour ; it contains oxalic and acetic acids, much diluted with water. Thenard, in his researches on this subject, found, that the elastic fluid disengaged during the process, consists of nitrogen, nitric and nitrous oxide, and carbonic acid gases, holding dissolved ether, and a portion of acid partly nitrous, partly acetic. The nitric ether, w hich is condensed, has also combined with it nitric and acetic acids; and when these are abstracted, so that it has no sensible acidity, it acquires this merely on keeping, a proof that the elements of these acids exist in its composition. From the products obtained from its decomposition by transmitting it through an ignited tube, he infers, that 100 parts of it consist of 16.41 of nitrogen, 39.27 of carbon, 34.73 of oxy gen, and 9.o9 of hydrogen. In its formation, much of the oxygen of the acid appears to combine with the hydrogen of the alcohol, forming water; a portion of it unites with part of the carbon, forming carbonic acid, and with portions of both producing acetic acid ; a considerable part of the nitrogen of the acid is disengaged in its insulated state, or in the form of nitric and nitrous oxides, and the remaining oxygen and nitrogen combine with the remaining carbon and hydrogen, and form the nitric ether. Nitric ether is light and volatile ; its colour is usually yellow, probably, however, from the presence of a portion of free nitric acid surcharged with nitric oxide : its SALTS. 148 odour is strong and penetrating, though not so fragrant as that of sulphuric ether ; when pure and concentrated its* volatility is such, that it instantly evaporates when poured from a phial, and boils at 70° under the common atmospheric pressure ; it is highly inflammable : with alcohol it combines in every proportion, but in water it is soluble onl) in limited quantity, requiring, according to Thenard, when pure, oO parts for its solution. This ether has scarcely in its pure form been applied to any medicinal use ; though it not improbably is possessed of powers analogous to those of sulphuric ether. Diluted with alcohol with a portion of free acid, it forms the following preparation, which has long had a place in the Pharmacopoeias, and is used as a refrigerant and diuretic. Spiritus atheris nitrosi. Spirit of Nitrous Ether. (Spiritus yEtheris Nitrici, Ph. Lond. —Spiritus .Ethereus Nitrosus, Ph. Dub. " Take of Alcohol, three pounds ; Nitrous acid, one pound. Pour the alcohol into a large phial placed in a vessel full of cold water, and add the acid gradually, agitating them frequently. Close the phial lightly, and set it aside for seven days in a cool place ; then distil the liquor with the heat of boiling water into a receiver kept cold with water or snow, as long as any spirit comes over." In the Pharmacopoeia of the London College, a smaller proportion of acid is added, three ounces only to two pints of rectified spirit, and twentysix ounces are distilled off immediately by a gentle heat. A preparation of this kind has long been employed in medicine. It consists probably of nitric ether diluted with alcohol, and containing always a portion of free acid. It is not difficult to add the nitric acid to the alcohol in the proportion of one to three parts, at least from this quantity of acid added with precaution, no violent action results If heat were applied to this mixture however, so as to raise it to 212°, mutual decomposition? SATLS. 149 attended with the rapid extrication of elastic products would take place. The heat must therefore be either applied more slowly, or the method ordered by the Edinburgh College must be followed, that of allowing the mixture to stand for some days in a cool place. During this time, a mutual action is exerted between the acid and alcohol ; the former is partially decomposed, and the heat required for distillation, can be safely applied. That this decomposition takes place is proved by the experiments of Bayen. He digested an ounce of nitrous acid with two ounces of alcohol for five weeks; the liquor then required for its saturation only 134 grains of an alkaline base, while an ounce of the same acid required to saturate it 282 grains of the same base. And when, after digesting the acid and alcohol together, he submitted them to distillation, on mingling the product and the residual liquor, the whole was capable of neutralizing only 32 grains. By this reciprocal action of the acid and alcohol, a portion of nitric ether appears to be formed; this nitric ether distils over with a considerable portion of unchanged alcohol, and a quantity of free acid. The theory of its production, therefore, so far as relates to the formation of the nitric ether, is the same with that which has been already explained. The propriety of the change which has been made by the London College, in this process, that of diminishing so much the proportion of nitric acid, may be questioned, both as less nitric ether must be formed when the proportion of acid is so small, and as a considerable share of the medicinal efficacy of the preparation probably depends on the free acid. Spirit of nitric ether has an odour extremely fragrant ; its taste is pungent and acidulous ; it is volatile and inflammable, soluble readily both in alcohol and in water. It is employed principally as a grateful refrigerant in inflammatory affections, as a diuretic in dropsy, or rather as an auxiliary to promote the operation of more powerful diuretics, and as a stimulant relieving nausea and flatulence. Its dose is 30 or 40 drops taken in a cupfwl of water SALTS. 150 The Dublin College give a formula for the preparation of a spirit of nitrous ether, which must afford a product considerably different from that obtained by me preceding processes, particularly in containing no free acid. The directions are to " add to what remains after the distillation of nitrous ether the rectified spirit of wine which had been employed in the process to con dense the elastic vapour, and distil with the highest heat of a water-bath to dryness. Mix this distilled liquid with the alkaline solution remaining after the separation of the nitrous ether, and add also as much dry sub-carbonate of potash as shall be sufficient to neutralize the free acid, ascertaining this by the test of litmus. Lastly, distil this with the mean heat of a water-bath while any liquid comes over. The specific gravity of the distilled spirit is to that of distilled water as 880 to 1000." By this process, the portion of nitric ether in the residuum of the first distillation is obtained, and the alcohol which had been in part also impregnated with it, is farther changed by the free nitric acid of the residual liquor. The product, therefore, is somewhat analogous to that obtained by the preceding processes. But by the action of the alkali, to which it is afterwards submitted, its acidity must be removed, and to a certain extent this must modify its medicinal powers. The product of the process which has been longest in use, that of the Edinburgh Pharmacopoeia, and the powers of which are sufficiently ascertained, is probably that which ought to be preferred. Carbonas potassa. Carbonate of Potash Ph. Ed. (Sub-Carbonas Potassse, Ph. Lond. —Sub-Carbonas Kali, Ph. Dub.') " Let impure Carbonate of Potash be put into a crucible, and exposed to a red heat, that the oily impurities, if any are present, may be burnt out; then having rubbed it with an equal weight of water, mix them thoroughly by agitation. The liquor, after the impurities have subsided, being poured into a clean iron pot, is to be boil- SALTS. 151 ©d to dryness, stirring the salt constantly towards the end of the boiling, that it may not adhere to the vessel." The directions given in the other Pharmacopoeias are essentially the same, except that in the London Pharmacopoeia the liquor is not ordered to be evaporated to dryness, but until it become thick ; it is then removed from the fire, and stirred with an iron rod, until it concrete into crystalline grains. The Potash of commerce is obtained by the incineration of the wood of land vegetables; the ashes being lixiviated with water, so as to dissolve the saline matter, and this being evaporated to dryness. The dry mass consists principally of sub-carbonate of potash, with smaller quantities of sulphate and muriate of potash, siliceous earth, and metallic matter, principally oxides of manganese and iron. These are in a great measure abstracted by the present process, the sub-carbonate of potash from its greater solubility being dissolved, while the others, and especially the earthy and metallic matter, from the small quantity of water employed, remain undissolved. It is obtained at least sufficiently pure for medicinal or pharmaceutical use. This saline matter is in the state of sub-carbonate, and is therefore improperly named in the Edinburgh Pharmacopoeia. It is deliquescent, acrid, changes the vegetable colours to a green, and has the general alkaline properties. It consists, according to Kirwan, of about sixty of potash, thirty of carbonic acid, and six of water, with a few grains of sulphate of potash, siliceous and argillaceous earth. It is rarely applied to any medicinal use, but is employed principally as an agent in Pharmacy. A solution of it is inserted in the Dublin Pharmacopoeia, under the name of aqua sub-carbonatis kali, obtained by exposing the sub-carbonate in a funnel, in the tube of which is a piece of linen, to a humid atmosphere; the solution formed by the water, slowly imbibed from the atmosphere, being received in a vessel beneath. A similar solution, liquor potassae -ub-carbonatis, is obtained, according to a formula SALTS 152 in the London Pharmacopoeia, by dissolving a pound of sub-carbonate of potash in twelve ounces of water. Garbonas potassa purissimus, olim, Sal Tartari Pure Carbonate of Potash, formerly Salt of Tartar. (Kali e Tartaro, Ph. Dub.) " Take of impure Super-tartrate of Potash, any quantity. Having wrapped it up in moist bibulous paper, or put it into a crucible, burn it into a black mass, by placing it among live coals. Having reduced it to powder, subject it to a moderate heat, in an open crucible, until it become white, or at least of an ash-gray colour, care being taken that it do not melt. Then dissolve it in warm water; strain the liquor through linen, and evaporate it in a clean iron vessel, stirring the matter constantly towards the end of the evaporation, with an iron spoon that it may not adhere to the bottom of the vessel. A very white salt will remain, which is to be left a little longer on the fire, until the bottom of the vessel is nearly at a red heat. When cold it is to be kept in glass vessels, well stopped." The same directions nearly are given in the'Dublin Pharmacopoeia, and this salt has also a place in the London Pharmacopoeia. By exposing the super-tartrate of potash to heat, the tartaric acid is decomposed. Part of its carbon and oxygene unite, and form carbonic acid, which is attracted by the potash; and, by continuing the heat, the remaining carbonaceous matter is burnt out. The super-tartrate of potash of commerce usually contains a little tartrate of lime, which, by the heat is converted into carbonate of lime, but by dissolving the saline matter in water, this, and any other earthy substances are separated, and, by evaporation, a salt is obtained, which, like the former, is a sub-carbonate of potash, but more pure. It appears also to contain rather a larger proportion of carbonic acid. The process, however, being more expensive than the preceding one, it is not often to be found in the shops. SALTS 153 Carbonas potass.*:. Carbonate of Potnsh Ph. Lond. H Take of Sub Carbonate of Potash," prepared from Tartar, a pound ; Carbonate of Ammonia, three ounces; Distilled Water, a pint. Add to the potash dissolved in the water, the carbonate of ammonia; then, by a sandbath, apply a heat of 180 degrees for three hours, or until the ammonia is expelled, and put the liquor aside that crystals may form. Let the residual liquor be reduced by evaporation, in a similar manner, so that when set aside it may again afford crystals." The intention of this process is to obtain potash fully saturated with carbonic acid, or in the state of the neutral carbonate, the carbonic acid required for this being abstracted from the ammonia, and the ammonia itself being expelled. The same object is obtained with equal certainty and facility, by transmitting a current of carbonic acid gas through a solution of one part of subcarbonate of potashf in three of water ; and the crystallized salt is obtained probably more pure, as in the former method it is difficult to expel the ammonia entirely. The carbonate crystallizes in quadrangular prisms, which are not deliquescent: they are soluble in four parrs of cold water. The taste of this sab is mild, but somewhat alkaline, and it changes the vegetable colours to a green. It is therefore disposed to crystallize with an excess of base, and is, in strictness of chemical language, a sub-carbonate. According to Pelletier, it consists of 40 of potash, 43 of carbonic acid, and 17 of water. It has been proposed to be used in medicine as a diuretic and antacid, in preference to the sub-carbonate, as being milder; and it answers better for preparing the effervescing draught. Aqua super-carbonatis potass-e. Water of Super-Carbonate oft Potash. " Take of Water, ten pounds ; Pure Carbonate of Potash, one ounce; Dissolve, and expose the solution to the current of Carbonic Acid Gas, which arises from Vol. It. %\ 154 SALTS three ounces of powder of Carbonate of Lime, three ounces of Sulphuric Acid, and three pounds of Water, gradually and cautiously mixed. The chemical apparatus invented by Dr. Nooth is well adapted to this preparation. But, if a larger quantity of the solution is required, the apparatus of Woolfe is preferable. The colder the air is, and the greater the pressure, the better will be the liquor. It ought to be kept in vessels well stopt." Potash, when used as a lithontriptic, excites so much irritation in the stomach and bladder, that its use cannot well be long continued. But, when super-saturated with carbonic acid, as it is in this preparation, it is rendered more pleasant and less irritating ; and, though its lithontriptic or real solvent power is diminished, or perhaps entirely lost, it is capable of acting as a palliative, and of being continued for any length of time ; and from the observations already made under class of lithontriptics, it follows, that no greater advantage is to be expected from the use of alkaline remedies under any form. It is taken to the extent of one, or even two pounds in the day. It affords also a grateful antacid. A solution of this kind has been in use for a considerable time; and to establish uniformity in its strength, it is properly inserted by the Edinburgh College as an officinal preparation. When properly prepared, it is pungent and acidulous, and sparkles when poured into a glass. By employing an apparatus, in which strong mechanical pressure can be applied, the solution may be still more impregnated with carbonic acid: it is thus rendered more grateful, and as an antacid, in particular, is perhaps rendered more effectual, the stimulus of the carbonic acid relieving the uneasy sensations connected with acidity of the stomach, while the alkali neutralizes the acid itself. Aq.ua POTASSiE, vulgo Lixivium Causticum. Water of Potash. " Take of newly prepared Lime, eight ounces; Carbonate of Potash, six ounces. Put the lime into an iron SALTS. 155 or earthen vessel, with twenty-eight ounces of warm water. The ebullition being finished, immediately add the salt; and the whole being well mixed, close the vessel until they become cold. Let the cold materials, previously well agitated, be poured into a glass funnel, the tube of which is obstructed with clean linen. Cover the upper orifice of the funnel, while the neck of it is inserted in another glass vessel, that the water of potash may gradually drop through the linen into the lower vessel. When it first ceases to drop, pour into the funnel a few ounces of water, but cautiously, so that it may swim above the matter The water of potash will again begin to diop. In this manner the affusion of water is to be repeated, until three pounds have filtered, which will be in the space of two or three days. The upper parts of the liquor are to be mixed with the lower by agitation, and it is to be kept in a vessel well stopt." The directions given in the London and Dublin Pharmacopoeias are essentially the same. A test is added to judge of the proper preparation of the solution, that it should be colourless, and scarcely effervesce on the addition of an acid. If on this addition any effervescence should take place, the liquor is to be again digested with a little lime, and filtered in a similar manner. This process affords a very good example of the action exerted on an acid by two bases having an attraction to it, and of the effect of quantity of matter in influencing the results of chemical affinity. To the carbonic acid combined with the potash, an attraction is exerted by the lime, and by this attraction part of the acid would be withdrawn. A portion of it, however, would still remain united with the potash ; and the only mode of counteracting this, and of at least diminishing the quantity, is to increase the proportion of lime acting on the carbonate. From the insolubility of lime, this can scarcely be done in any other mode than that followed in the present process, in which by the arrangement of putting the entire mix ure, with a great excess of lime, into a funnel, the tube of which is nearly SALTS. 156 obstructed, the alkaline solution must filtrate slowly through the mass of lime. The affinity, of the lime to the carbonic acid is thus favored, and the greater part oft he acid is abstracted from the potash. Still, however, from the effect of quantity on the force with which affinity is exerted, a small quantity of acid is retained in combination wiih the potash, which cannot be abstracted by this process. But if the lime has been in a sufficiently active state, and the directions observed so that the filtration has been performed slowly, the quantity is very inconsiderable, as is apparent from scarcely any sensible effervescence being excited by the addition of an acid, and for any mediciual or pharmaceutical purpose to which the solution is applied may be neglected. The agency of the air must be excluded during the filtration, especially from the filtered liquid, to prevent absorption of carbonic acid ; and for the same reason it must, after it is prepared, be kept in glass vessels well stopt. Its specific gravity is to that of distilled water as 1220 to 1000. The medicinal applications of the alkali under this form have been already considered. Potassa, olim Causticum Commune Acerrimum. Potash. (Potassa Fusa, Ph. Lond. —Kali Causticum, Ph. Dub.) " Take of Water of Potash, any quantity. Evaporate it in a covered clean iron vessel, until when the ebullition is finished, the saline matter flow smoothly like oil, which will happjn before the vessel is at a red heat. Then pour it on a clean iron plate ; cut it into small masses before it hardens, and immediately put them into a phial well stopt." By the dissipation of the water, the alkali is obtained in a solid form ; it is usually run into moulds, so as to be formed into cylindrical pieces. Under this form it is used as a caustic : it quickly erodes animal matter, and, mixed with soap into a paste, is sometimes used to open an ulcer. SALTS. 157 Potassa cum calce, olim Causticum Commune Mitius. Potash with Lime. (Potassa cum Calce, Ph. Lond. —Kali Causticum cum Calce, Ph Dub.) " Take of Water of Potash, any quantity. Evaporate it to one-third in a covered iron vessel; then mix with it as much newly slacked lime as may be sufficient to give it the consistence of a solid paste, which is to be kept in a stopt vessel." As a caustic, this is milder than the former preparation, and it has the advantage of being less deliquescent, so that it can be more easily confined to the part to which it is applied. When mixed, however, with the requisite quantity of soap to form a paste, it is scarcely sufficiently active. Acetis potassae. Acetite of Potash. (Potassa; Acetas, Ph. Lond, Acetas Kali, Ph. Dub.) " Take of Pure Carbonate of Potash, one pound. Boil it with a gentle heat in four or five times its weight of Distilled Acetous Acid, and add more acid at different times, until, on the watery part of the former portion being nearly dissipated by evaporation, the acid newly added excite no effervescence : this will happen when about twenty pounds of acid have been consumed. Afterwards evaporate to dryness slowly. Let the remaining impure salt be liquefied with a gentle heat, for a short time ; then dissolved in water, and strained through paper. If the liquefaction has been properly done, the strained liquor will be limpid; if not, of a brown colour. Afterwards evaporate with a very gentle heat this liquor, in a shallow glass vessel, stirring the salt while it concretes, that it may more quickly be brought to dryness. Lastly, the acetite of potash ought to be kept in a glass vessel, well closed, that it may not liquefy by the action of the air." In this process, the acetic acid of the distilled vinegar combines with the potash, disengaging the carbonic acid. The acetate of potash, obtained by the evaporation, is liable to be of a brownish colour, from the pre- SALTS. 158 sence, probably, of a little extractive matter derived, from the vinegar. It is freed from this, either by boiling the solution with charcoal powder; or, as directed in the Pharmacopoeia, by melting the salt; and, by the second solution and evaporation, it is obtained in the form of a white foliated mass; the foliated structure which is very characteristic of this salt, arising from a species of crystallization it suffers. Acetate of potash is extremely deliquescent, becoming humid in a very short time from exposure to the air. It does not require more than its weight of water for its solution, at the temperature of 60° : it was at one time celebrated as a diuretic, in a dose of one or«two drachms ; but it has now nearly fallen into disuse. Sulphas potassje, olim Tartarum Vitriolatum. Sulphate of Potash. (Potassae Sulphas, Ph. Lond. —Sulphas Kali, Ph. Dub.) " Take of Sulphuric Acid, diluted with six times its weight of Water, any quantity. Put it into a large glass vessel, and gradually drop into it, of Carbonate of Potash, dissolved in six times its weight of Water, as much as may be necessary to the perfect saturation of the acid. The effervescence being over, strain the liquor through paper; and, after due evaporation, put it aside, that crystals may form. Sulphate of Potash may also be conveniently made, by dissolving the residuum of the distillation of Nitrous Acid in Warm Water, and saturating it by adding Carbonate of Potash." In the former of these processes, the sulphuric acid unites with the potash of the carbonate of potash, and expels the carbonic acid with effervescence, the sulphate of potash remaining in solution. The second process being more economical, is that which is always followed, and it is it which has a place in the other Pharmacopoeias. The salt remaining after the distillation of nitrous acid, is sulphate of potash, with a considerable excess of sulphuric acid: this excess of acid is neutralized by the potash of the carbonate of potash. The neutral salt forms only in small crystals, the figure ©f SALTS. 159 whieh is a six-sided prism, acuminated by six planes : by slow evaporation they are obtained of a larger size. They require seventeen parts of cold water for their solution. The taste of the salt is bitter. Its powers are those of a cathartic, in the dose of half an ounce ; but it is more usually given in smaller doses as an aperient, and, from its sparing solubility, is given usually in powder. Sulphas potassa cum sulphure, olim Sal Polychrestus. Sulphate of Potash with Sulphur. Ph. Ed. " Take of Nitrate of Potash in powder, Sublimed Sulphur, equal weights. Throw them well mixed together, in small quantities at a time, into a red-hot crucible. The deflagration being finished, let the salt cool, and keep it in a glass phial well stopt." The nitrate of potash being decomposed at a red heat, affords oxygen to the sulphur, in such proportions as to convert it principally into sulphuric, and partly into sulphurous acid. Both acids are attracted by the potash ; and it appears even that from the rapidity of the deflagration, a portion of the sulphur escapes oxygenation, and remains united with a portion of the alkali. This is therefore a mingled product. In its medicinal qualities, it does not appear to differ from the sulphate of potash ; and it is soon converted into it, by exposure to the air. Hence it is little used. Potassje super-sulphas. Super-Sulphate of Potash. Ph. Lond. " Take of the salt which remains after the distillation of Nitric acid, two pounds ; Boiling Water, four pints. Mix them, so that the salt may be dissolved, and strain. Then boil the solution until a pellicle appear on its surface, and put it aside that crystals may form. The liquor being withdrawn, dry these on bibulous paper." Bv solution in water, the free acid of the residual mass is in part removed, but the salt still crystallizes with an excess of acid. It is much more soluble than SALTS 160 the neutral sulphate, but it is not very apparent to what medicinal use it can be applied, with any peculiar advantage. Tartaris potasstb, olim Tartarim Solubile. Tartrite of Potash. (Potassae Tartras, Ph. Lond. —Tartaras Kali, Ph. Dub.) " Take of Carbonate of Potash, one pound ; Super- Tartrite of Potash, three pounds, or as much as may be necessary ; Boiling Water fifteen pounds. To the carbonate of potash ffissolved in the water, add, by small quantities, the Super-Tartrite of Potash rubbed to a fine powder, as long as it excites effervescence, which generally ceases before three times the weight of the carbonate of potash have been thrown in. Then strain the liquor when cold, through paper; and, after due evaporation, put it aside that crystals may form." The excess of tartaric acid in the super-tartrate of potash, is in this process saturated by the potash of the carbonate of potash, and the proper neutral salt is formed. Though ordered to be crystallized in all the Pharmacopoeias, the crystallization of it can scarcely be accomplished by hasty evaporation. In its preparation, therefore, the solution is usually evaporated to dryness, and it is kept in powder in the shops. This salt has a bitter taste ; it is very soluble in water, requiring only four parts of cold water for its solution ; and from this greater solubility compared with that of the super-tartrate, it derived its name of Soluble Tartar. Even the weaker acids decompose it partially, and reduce it to the state of super-tartrate. As a purgative, it is given in the dose of one ounce. Sulphuretum potassae, olim Hepar Sulphuris. Sulphuret of Potash. (Potassae Sulphuretum, Ph. Lond. —Sulphuretum Kali, Ph. Dub.) " Take of Carbonate of Potash, Sublimed Sulphur, of each eight ounces. Having rubbed them together, put them into a large coated crucible ; and a cover being adapted to it, apply the fire to it cautiously, until they SALTS. 161 melt. The crucible, after it has cooled, being broken, remove the sulphuret, and preserve it in a phial well stopt." The formula in the Dublin Pharmacopoeia is the same ; but in the London Pharmacopoeia the proportions are very different, one ounce of sulphur being heated in a covered crucible with five ounces of sub-carbonate of potash, until they unite: the advantage supposed to be derived from this large proportion of alkali, is, that the w hole sulphur is rendered soluble in water. During the fusion of the two substances, the sulphur and potash combine, and the carbonic acid is disengaged, only partially, however, and hence the combination is less perfect than when the sulphur is melted with the pure alkali. The compound is easily fusible, and is of a yellowish, green or brown colour, and inodorous, but becomes foetid when moistened or dissolved in water from partial decomposition, .and the production of a compound of sulphur and hydrogen. It has been proposed to be used as an antidote to some of the metallic poisons, from the supposition that the sulphur will combine with the metallic preparation, and render it inert. From a similar theory, it has been imagined that it might obviate the effects of mercury on the system when these are too violent: but it is very seldom had recourse to with either intention, and it is doubtful if much advantage would be derived from it. The dose in which it has been proposed to be given is from ten to twenty grains, three or four times a day. It is said, in some cases of cancer, to have increased the efficacy of cicuta as a palliative, in doses of five grains. Aq.ua sulphureti kali. Water of Sulphuret of Potash. Ph. Dub. " Take of Sublimed Sulphur, half an ounce ; of Water of Potash, nine ounces. Boil them together for ten minutes, and filter the liquor through paper. Keep it in phials closely stopt. The specific gravity of this liquor is to that of distilled water as 1120 to 1000." The alkali in its pure form, and in this state of solu- Vol. II. 22 SALTS. 162 tion, acts readily on the sulphur and dissolves it, the liquor being of a dark yellow or red colour. It is not merely, however, a solution of sulphuret of potash in water ; for whenever sulphur is combined with an alkaline base, it partially decomposes water, and in the state of solution, therefore, a new compound is formed. The nature of their re-action is somewhat complicated. A portion of the sulphur attracts a portion of the oxygen of the water, and the sulphuric acid thus formed is combined with a part of the alkaline base. The hydrogen of the decomposed water enters into union with the remaining sulphur, forming the compound with excess of sulphur, named Super-Sulphuretted Hydrogen, and this remains combined with the rest of the base, forming what some chemists have named a Hy drogu retted Sulphuret,—what may be distinguished by the less harsh appellation of a Sulphuretted Hydro-sulphuret. The solus ion, as prepared by the above formula, is adapted to the same uses as the sulphuret of potash. Carbonas sod;e. Carbonate of Soda. (Carbonas Sodae, Ph. Dub. — Sub-Carbonas Sodae, Ph. Lond.) " Take of impure Carbonate of Soda, any quantity. Bruise it, and boil it in water until all the saline matter is dissolved. Strain the solution through paper, and evaporate it in an iron vessel, so that on cooling crystals shall form." The barilla of commerce, from which this salt is ordered to be prepared, is the residual matter of the combustion of marine plants. It is a very impure carbonate oi soda, containing large quantities of other saline and earthy matter, chiefly sulphate and muriate of soda, lime, magnesia, argil and silex, with charcoal. The subcarbonate of soda crystallizing readily, the solution on being evaporated affords it nearly pure in the crystals which first form. The residual liquor, containing more of the other salts, ought to be rejected, a direction properly given in the formula of the London Pharmacopoeia. From three to five ounces of the crystallized salt are obtained from a pound of barilla. SALTS 163 This crystallized salt, though mild to the taste, is still sensibly alkaline, and it changes the vegetable colours to a green. It is therefore, in the strictness of chemical nomenclature, a sub-carbonate, as the London ( ollege have named it. It crystallizes in octohedrons; its crystals are efflorescent; they require not more than twice their weight of cold water for their solution ; and by a heat, inferior to that of 212° are liquefied by the action of the very large quantity of water of crystallization they contain. Its quantity amounts to 64 parts in 100, with 21.6 of soda, and 14.4 of carbonic acid. The use of this salt, as a lithontriptic has been already stated; and for its more convenient exhibition, it is ordered in the London and Dublin Pharmacopoeias to be kept dried. Sodje sub-carbonas exsiccata. Dried Sub-carbonate of Soda, Ph. Lond. —(Carbonas Sodae Siccatum, Ph. Dub.) " Take of Sub-carbonate of Soda, a pound. Submit: it to the heat of boiling water in a clean iron vessel until it is perfectly dry, stirring it constantly with an iron spathula. Then rub it into powder." Carbonate of soda has been given as a lithontriptic. principally mixed with soap under the form of pill. If the crystallized salt be used, besides the addition to its bulk from the water of crystallization, it effloresces, so that the pill prepared from it soon loses its cohesion. The. dried carbonate is therefore preferable ; and from the moderate heat to which it is exposed in the drying, the water merely is expelled. Sodje carbonas. Carbonate of Soda. Ph. Lond. " Take of Sub-carbonate of Soda, a pound ; Sub-carbonate of Ammonia, three ounces; Distilled water, a pint. To the sub-carbonate of soda dissolved in the water, add the ammonia ; then by a sand-bath apply a heat of 180° for three hours, or until the ammonia is expelled, and put it aside, that crystals may form. Let the remaining liquet be evaporated in a similar manner, and put aside, that crystals may again be produced." SALTS 164 The sub-carbonate of soda will in this process receive carbonic acid from the carbonate of ammonia, and be brought to the neutral state, while the ammonia will be expelled by the heat. The same neutralization might be effected more directly and economically, by transmitting a current of carbonic acid gas through the solution of the sub-carbonate. The salt in this state, however, does not appear to possess any particular advantage for medicinal or pharmaceutical use. Aq.ua super-carbonatis soDyE. Water of Super-Carbonate of Soda. Ph. Ed. " This is to be prepared from ten pounds of Water, and two ounces of Carbonate of Soda, in the same manner as the Water of Super-Carbonate of Potash." The proportion of the carbonate to the water is greater in this preparation than in that of the super-carbonate of potash water ; but this is owing to the carbonate of soda containing so much water of the crystallization, that even with the enlarged proportion, there is not more real alkali in the one than in the other. The supercarbonated soda water is used as a lithontriptic in the same dose as the super-carbonated potash water, and is usually preferred, on the supposition of being more pure and mild. Tartris potassje et SODJE, olim Sal Rupellensis. Tartrite of Potash and Soda. (Soda Tartarizata, Ph. Lond. —Tartaras Soda? et Kali, Ph. Dub.) " This is prepared from Carbonate of Soda and Super-Tartrate of Potash, in the same manner as Tartrate of Potash." The excess of tartaric acid in the super-tartrate of potash, being saturated in this preparation by the soda of the carbonate of soda, a triple salt is formed properly named by the Edinburgh College, Tartrate of Potash and Soda. It crystallizes in rhomboidal prisms ; is soluble in five parts of water at 60°, and has a bitter saline taste. It consists, as Vauuuelin has stated its composi- SALTS 165 lion, of 54 parts of tartrate of potash, and 46 of tartrate of soda. Jt is employed as a cathartic* in the dose of one ounce ; and is often preferred, as being less disagreeable than the greater number of the saline cathartics. Phosphas sodje Phosphate of Soda. (Phosph. Sodae, Ph. Dub.) " Take of Bones, burnt to whiteness, and reduced to powder, ten pounds; Sulphuric Acid, six pounds; Water, nine pounds. Mix the powder in an earthen vessel with the sulphuric acid ; then add the water, and again mix them. Keep the vessel in the vapour arising from boiling water for three days; at the end of which, dilute the matter, by adding other nine pounds of Boiling Water, and strain through a strong linen cloth, pouring over it gradually, boiling water, until the whole acid is washed out. Put aside the strained liquor, that the impurities may subside, from which pour it off, and, by evaporation, reduce it to nine pounds. To this liquor, again poured off from the impurities, and heated in an earthen vessel, add Carbonate of Soda dissolved in warm water, until the effervescence cease. Then strain, and put it aside, that crystals may form. These being removed, add, if necessary to the liquor, a little Carbonate of Soda, that the phosphoric acid may be exactly saturated ; and prepare it, by evaporation, again to form crystals, as long as these can be produced. Lastly, let the orystals be kept in a vessel well stopt." The white residuum of burnt bones consists chiefly of phosphate of lime. The sulphuric acid partially decomposes it, by combining with the lime; the phosphoric acid which is disengaged, in conformity to the law of eliemical attraction, that quantity of matter influences affinity, and that in all cases where two acids act on a base, there is a participation of this base between them, in proportions determined by their respective quantities and affinities, retains a quantity of lime combined with it, forming a soluble compound. When carbonate of soda is added to the acidulous liquor obtained by washing the materials, the soda combine* 166 SALTS with the free phosphoric acid, and the lime retaining as much phosphoric acid in combination as forms neutral phosphate of lime, is precipitated; the phosphate of soda crystallizes on evaporation of the strained liquor. Its crystals are rhomboidal prisms, and are obtained of a regular figure only in crystallizing with a slight excess of alkali. Hence the liquor should be slightly alkaline; and from the tendency of the salt to crystallize with an excess of base, it is necessary, though the neutralization may have been perfect, to add, previous to the second crystallization, a little carbonate of soda. The crystals are efflorescent; they are soluble in little more than three parts of cold, and in half that quantity of boiling water. They consist, according to Thenard, of 19 of soda, 15 of acid, and 66 of water. The taste of this salt is purely saline, without any bitterness; its medicinal operation is that of a mild cathartic, and, from being less nauseous to the taste than the other salts, it is entitled to preference. Its dose is one ounce, given generally dissolved in six ounces of tepid water, or soup. Sulphas sodje, olim Sal Glauberi. Sulphate of Soda. (Sulphas Sodas, Ph. Lond. Dub.) 11 Dissolve the acidulous Salt, which remains after the distillation of muriatic acid,in Water; and add to it, Carbonate of Lime in powder, to remove the superfluous acid. Put it aside until the impurities have subsided; then having poured off the liquor, and strained it through paper, reduce it by evaporation, that crystals may be formed." The London College order the excess of sulphuric acid to be neutralized by carbonate of soda, but it is more economical to use carbonate of lime. Slacked lime is preferable to either, as it decomposes a little muriate of iron, w hich adheres to the salt. In the decomposition of muriate of soda by sulphuric acid, to prepare muriatic acid, more sulphuric acid is used than is necessary merely to saturate the soda, advantage being gained from its quantity adding to its affinity, as has been already explained; hence the ne- SALTS. 167 cessity of removing the excess of acid in the residual mass, to obtain the neutral sulphate. This salt is also obtained as a residuum in some other processes, particularly in the preparation on a large scale of muriate of ammonia, the Sal Ammoniac of commerce. It crystallizes in hexhaedra) prisms; they are efflorescent and soluble in rather less than three parts ot cold water. They consist of 18.48 of soda, 23.52 of acid, and 58 of water. I his salt has long been in use as a cathartic ; it operates with sufficient power and certainty, but is liable to occasion nausea, from its very bitter taste. Its medium dose is an ounce and a half. Gakbonas ammonle, olim Ammonia Prceparata. Carbonate of Ammonia. (Carbonas Ammoniae, Ph. Lond. Dub.) " Take of Muriate of Ammonia, one pound ; Carbonate of Lime, commonly called Chalk, dried, two pounds. Each being separately reduced to powder, mix them, and sublime trom a retort into a receiver kept cold." In this process the muriatic acid of the muriate of ammonia combines with the lime of the carbonate of lime, and the carbonic acid of the latter unites with the ammonia of the former; the exertion of these new affinities being determined by the heat applied. The carbonate of ammonia which is formed is sublimed, and is obtained in a crystalline cake. When the process is carried on in the large way, the sublimation is generally performed from an iron pot, to which the heat is directly applied, and which is connected with a large earthen or leaden receiver. The Dublin College, in place of carbonate of lime, direc; carbonate of soda to be used ; w ith this the application of so high a heat will not be required ; but not being economical, the direction will not be attended to by the practical chemist. According to the experiments of Mr. Davy, earbona'e of ammonia varies in the proportions of its ingredients according to the heat applied in its preparation : SALTS. 168 they vary so much as from 20 to 50 parts of ammonia in 100, the ammonia being in larger proportion, as the temperature at which the carbonate has been formed is high ; that formed at a temperature of 300° containing 50 parts of alkali, while that produced at a temperature of 60° contains only 20 parts. Still in all these proportions the product is a sub-carbonate ; its smell is pungent and ammoniacal, and it changes the vegetable colours to a green : It is very volatile, abundantly soluble in water, and is efflorescent on exposure to the air. Its medicinal uses are as a stimulant applied to the nostrils in fainting, and as a stimulant and diaphoretic, taken internally, in a dose of from five to fifteen grains. Aq.ua carbonatis ammoni/e, olim Aqua Ammoniae. Water of Carbonate of Ammonia. (Aq. Carbonatis Ammoniae, Ph. Dub.) " Take of Muriate of Ammonia, Carbonate of Potash, of each sixteen ounces ; Water, two pounds. To the salts, mixed and put into a glass retort , add the water ; then distil from the sand-bath with a fire gradually raised to dryness," The Dublin College give the same process with the substitution of Carbonate of Soda for carbonate of potash, by which probably a larger quantity of carbonic acid will be combined with the ammonia. In this preparation of carbonate of ammonia by the humid way, carbonate of lime, from its insolubility could not be employed to decompose the muriate of ammonia, as it is in the drv way ; an alkaline carbonate is therefore employed. The alkali, whether potash or soda, attracts the muriatic acid, while the ammonia combines with the carbonic acid. The carbonate of ammonia is volatilized and dissolved by the watery vapour. The solution is applied to the same medicinal purposes as the concrete ammoniacal carbonate, and is generally preferred for internal use. A formula is given by the London College for a similar preparation, under the name of Liquor Carbonatis Ammoniae, obtained by the solution of the solid carbonate in water. Eight ounces of the carbonate of ammo- SALTS 169 iiia are dissolved in a pint of distilled water, and the solution is strained through paper. Liquor volatilis cornu cervi. Volatile Liquor of Hartshorn. Pharm. Dub. " Take of Hartshorn, any quantity. Put it into a retort, and distil, with a heat gradually raised, a volatile liquor, salt, and oil. Distil the volatile liquor repeatedly until it become limpid as water, separating, after each distillation, the salt and oil by filtration. The liquor will be purified more easily, if, after each distillation except the first, there be added to it a sixth part of its weight of charcoal, previously made red hot, extinguished by being covered with sand, and reduced to powder while hot. If hartshorn cannot be procured in sufficient quantity, the bones of any land animal may be employed in its place." This is a process which has long been employed in Pharmacy. The animal matter, principally the gelatin of the bones, at an elevated temperature suffers decomposition, and its principles enter into new combinations, forming chiefly carbonate of ammonia and empyreumatic oil. These are the products of the process ; the carbonate of ammonia being partly dissolved by the water which distils over, and obtained partly in a concrete state. It is always contaminated, however, with the empyreumatic oil, which renders it nauseous; and though at one time it was supposed, from this impregnation, to be possessed of some peculiar virtues, this probably had no just foundation, and it is now rejected from practice. If sublimed from charcoal powder, the oily matter is completely removed ; but then it differs in nothing from the carbonate of ammonia obtained by the preceding processes, and the process, with these repeated operations, is not more economical. Vol. II. 2$ 170 SALTS Aqua ammonia;, olim Aqua Ammonia; Caustics. Water of Ammonia. (Liquor Ammonia*, Ph. Lond. —Aqua Ammonias! Causticse, Phi Dub.) " Take of Muriate of Ammonia, one pound; Lime, recently prepared, a pound and a hall; Distilled Water, one pound ; Water, nine ounces. Pour the water upon the lime bruised in an iron or earthen vessel, closing the vessel until the lime, having fallen into powder, has become cold; then mix the muriate, rubbed to very fine powder, with the lime, rubbing them together in a mortar, and then put them into a retort of the coarser glass, (bottle glass.) Let the retort be placed in a sand-bath, and connect with it properly the apparatus of Woolfe. In the first bottle, of smaller size than the others, furnished with a tube of safety, put two ounces of distilled water ; and in the second vessel what remains of the distilled water. Then apply the fire, increasing gradually until the bottom of the iron pot is at a red heat, and as long as the ammonia is produced. Mix the liquor from both bottles, and let it be kept in small phials well stopt." The directions in the London Pharmacopoeia for conducting this process are nearly the same, except that the lime, without being previously slaked, is reduced to powder, and mixed with the muriate of ammonia, and to this mixture put into a retort, a pint of Water is added ; the lime will then be slaked, but it must be with some risk of the retort breaking from the sudden heat, and the ammoniacal gas must also be very vapidly disengaged. In the formula given by the Dublin College, a large quantity of water is mingled with the materials in the retort, and a portion only of this is drawn off by distillation, impregnated with the whole of the ammonia. In these processes, the lime combines with the muriatic acid of the muriate of ammonia, and the ammonia is disengaged. Being permanently elastic, it is condensed only by combination with the water, and this is effected either by distilling water at the same time from the materials, or by transmitting the ammoniacal gas throu^fe SALTS. 171 water. TheEdinburgh and London Colleges have preferred the latter mode, and they obtain a solution in this way, perhaps more strongly impregnated; the other mode is rather more easily conducted, and affords a product sufficiently strong for any medicinal or pharmaceutical purpose. On a large scale, an iron stili is employed, into which the materials are put, and to which, the lire can be directly applied ; the head of the still being connected with a spiral tube placed in a refrigeratory, to the extremity of which, besides the recipient to collect the condensed product, two or three receivers are adapted, containing water to absorb any ammoniacal gas. Water, under a common atmospheric pressure, and at a temperature below 50°, absorbs about one-third of its weight of gas ; and by this combination its specific gravity is diminished, that of the saturated solution being not more than 9054. It is seldom so completely impregnated. By following the mode directed by the Dublin College, which is that usually followed, the solution is obtained of the specific gravity of 936 ; and when of this strength, it contains about 16 of ammonia in 100 parts. Its smell is strong and pungent; its taste extremely acrid, and it inflames the skin. Though its odour is pungent, it ought to be free from any fcetor. It is employed in medicine as a stimulant and diaphoretic, internally, in a dose from twenty to thirty drops, and sometimes as an emetic in a larger dose diluted with water. Externally it is used as a stimulant applied to the nostrils, and as a rubefacient. Alcohol ammoniatum, olim Spiritus Ammonia. Ammoniated Alcoj hoi. (Spiritus Ammoniac, Ph. Lond. Dub.) " Take of Alcohol, thirty-two ounces: recently Pre pared Lime, twelve ounces ; Muriate of Ammonia, eightounces ; Water, eight ounces. From these, prepare the Ammoniated Alcohol in the same manner as the water of ammonia, and preserve it in a similar manner. This compound used formerly to be prepared by decomposing the muriate of ammonia by sub-csu'boaat© ef SALTS. 172 potash, and this method is still retained in the Dublin Pharmacopoeia. The result of it was, that as carbonate of ammonia is not soluble in alcohol, either the alcohol Was impregnated with the portion of ammouia only disengaged by the operation of the excess of alkali in the sub-carbonate on the muriate of ammonia, or that the distillation was carried so far, as to bring over with the alcohol a quantity of water sufficient to dissolve the carbonate of ammonia which had been produced. The Edinburgh College having substituted lime, it disengages the ammonia from the muriate of ammonia altogether in its pure form, and the ammoniacal gas is condensed by the alcohol. The London College order it to be prepared merely by mixing two parts of rectified spirit, and one of water of ammonia ; but in this way the alcohol is considerably diluted. Ammoniated alcohol has the pungent smell, and retains all the powers of ammonia. It is used principally as the menstruum of some vegetables with which ammonia coincides in medicinal operation. Alcohol Ammoniatum aromaticum, olim Spiritus Ammonia Aromaticus. Aromatic Ammoniated Alcohol. (Spiritus Ammoniac Aromat. Ph. Lond. Dub.) " Take of Ammoniated Alcohol, eight ounces; Volatile Oil of Rosemary, one drachm and a half; Volatile Oil of Lemon, one drachm. Mix them so as to dissolve the oils." In the London Pharmacopoeia, oil of cloves is ordered in place of oil of rosemary ; and in the Dublin, half an ounce of nutmeg, with two drachms of oil of lemons, are digested with two pounds of spirit of ammonia, and afterwards a pound and a half distilled off. By this combination of ammonia with alcohol, and the addition of the aromatic oils, it is rendered more grateful than the water of ammonia. This preparation is therefore frequently used in preference to the other, as a stimulant in languor or faintness, or to relieve flatulence. Its dose is from fifteen to thirty drops. Salts 173 Alcohol ammoniatum foetidum, olim Spiritus Ammonia Fcetidus. Foetid Ammoniated A:cohol. (Spiritus Amnion.» i uetidu», Ph. Lond. Hub.) ** Take of Ammotiiated Alcohol, eight ounces ; Assafcetida, half an ounce, Let them digest in a close vessel for twelve hours ; then distil eight ounces by the heat of boiling water." The impregnation of the ammoniated alcohol with part of the assafoetida in this process, though it may communicate a foetid smell, can add little to its activity; and accordingly, though it has a place in all the Pharmacopoeias, it is not found in the shops. It has been given in hysteria in a dose of thirty drops. Spiritus ammonle succinatus. Pharm. Lond. Succinated Spirit of Ammonia. " Take of Mastich, three drachms ; Alcohol, nine fluid drachms ; Oil of Lavender, fourteen minims; Oil of Amber, four minims ; Water of Ammonia, ten fluid ounces. Macerate the mastich in the alcohol, so that it may be dissolved, and pour off the clear solution ; add to this the other ingredients, and mix them all by agitation." Spirit of ammonia, impregnated with oil of amber and some other essential oils, had been in use as a stimulating perfume under the name of Eau de Luce. A composition had been introduced into the London Pharmacopoeia, as a substitute for this, which had not, however, its usual milky appearance. This is given in the present formula by the addition of the mastich, the resinous matter of which is separated by the water, but retained in a state of suspension, probably by the action of the alkali. Aq.ua acetitis ammonle, vulgo Spiritus Mindereri. Water of Acetate of Ammonia. (Liquor Ammoniae Acetatis, Ph. Lond. —Aqua Acetatis Ammoniae, Ph. Dub.) " Take of Carbonate of \ mmonia, any quantity. Pout upon it as much distilled acetous acid, as may be sufficient to saturate the ammonia exactly." SALTS. 174 The acetic acid of the distilled vinegar combines with the ammonia of the carbonate of ammonia, disengaging the carbonic acid with effervescence; and the acetate of ammonia being a very soluble suit, remains dissolved in the water. As the distilled vinegar is not uniform in strength, the precise proportion necessary to be added cannot be assigned, but in general it will be about thirty parts to one. As much must always be added as to produce neutralization; and as the liquid is sometimes used as an external application in cases where the acrimony of the alkali would be hurtful, it is better that there should be even a slight excess of acid. From the variable quantity of acid in the vinegar, the preparation cannot be of uniform strength, and this cannot be obviated by crystallizing the salt, the heat decomposing it which would be necessary to evaporate the water. Were it of any importance, a uniformity of strength might be obtained by ordering the quantity prepared from a given weight of carbonate of ammonia ro be reduced by slow evaporation to a certain measure ; but this is not necessary, the solution having no great activity, and being given generally in divided doses. It is employed as a diaphoretic in febrile affections, an ounce of it being given, and repeated twice or thrice at intervals of an hour, and its operation promoted by mild diluents. Externally it is used as a discutient, and likewise as an application in some forms of inflammation. Hydro-sulphuretum ammonle. Hydro-Sulphuret of Ammonia; (Hydro-Sulphuretum Ammoniae, Ph. Dub.) " Take of Water of Ammonia, four ounces. Expose it in a chemical apparatus to the stream of gas which arises from Sulphuret of Iron, four ounces ; Muriatic Acid, eight ounces, previously diluted with two pounds and a half of Water. The sulphuret of iron for this purpose is conveniently prepared from three parts of Purified Iron Filings, and one part of Sublimed Sulphur, mixed together, and exposed in a covered crucible to a moderate heat, until they unite. SALTS. 175 The sulphuretted hydrogen is produced in this process by the muriatic acid enabling the iron to decompose part of the water by attracting its oxygen. The hydrogen disengaged combines with a portion of the sulphur, and forms sulphuretted hydrogen ; and this elastic fluid being transmitted through the water of ammonia unites with it, and forms a liquid of a dark green colour, and a very fuetid odour. The medicinal applications of hydro-sulphuret of ammonia have been already taken notice of. It depresses the action of the stomach and digestive organs, and has been used from this quality in bulimia and in diabetes, in a dose of from five to ten drops twice a day. Aqua sulphureti ammonite. Water of Sulphuret of Ammonia. Ph. Dub. " Take of recently Prepared Lime, Muriate of Ammonia in powder, each lour ounces ; of Sublimed Sulphur, Warm Water, each two ounces. On the lime in an earthen vessel, sprinkle the water, and cover the vessel until the lime fall to powder. This, when cold, mix by trituration with the su phur and muriate of ammonia, avoiding the acrid vapour which arises. Put the mixture into a retort, and distil with a strong heat suddenly raised. Keep the liquor thus obtained in a phial closely stopped with a glass stopper." This preparation is similar to one long known to chemists by the name ol Fuming Liquor of Boyle, and which Berthollet considered as a hydro-sulphuret of ammonia much concentrased, with an excess or ammonia, to which he ascribed its fuming property. As muriatic acid, when added to it, causes not only a disengagement of sulphuretted dydrogen, but likewise a precipitation of sulphur, it is probably rather a sulphuretted hydro-sulphuret. It has not been applied to any medicinal use. Sulphas aluminje olim Alumen Latum. (Alumen Exsiccatum, Ph. Lond. —Alumen Ustum, Ph. Dub.) " Let Alum be liquefied in an earthen or iron vessel, and exposed to heat, until it cease to boil." SALTS. 176 In this process, the alum loses merely its water of crystallization; it is deprived of its hardness, and resolved into a spongy mass, easily reducible to a fine powder; and both from this, and from being rendered more active, it is better adapted to the purposes of an escharotic, to which it is applied. Liquor aluminis compositus. Compound Solution of Alum. Ph. Lond. "Take of Alum, Sulphate of Zinc, each, half an ounce; Boiling Water, two pints. Dissolve the alum and the sulphate of zinc in water; then strain through paper." This forms a strong astringent solution which has been employed to check haemorrhage or profuse mucous discharges; and when considerably diluted has been used as a collyrium. Murias barytje. Muriate of Barytes. Take of Carbonate of Barytes, Muriatic Acid, each, one part; Water, three parts. To the water and acid mixed together, add the carbonate, bruised into small pieces. The effervescence being finished, digest for an hour, then strain, and after due evaporation put the liquor aside that crystals may form. Repeat the evaporation as long as there is any formation of crystals. " If the carbonate of barytes cannot be procured, the muriate may be prepared from the sulphate, in the following manner: " Take of Sulphate of Barytes, two pounds; Wood Charcoal in powder, four ounces. Calcine the sulphate, that it may be the more easily reduced to a fine powder, with which is to be mixed the powder of charcoal. Put this into a crucible, and having adapted a cover, urge it with a strong fire for six hours. The matter being well triturated, put it into six pounds of Boiling Water, in a closed glass or earthen vessel, and mix them by agitation, preventing, as much as possible, the access of the air. Let the vessel stand in a vapour bath, until the part SALTS 177 not dissolved has subsided; then pour off the liquor. Pour on the residuum four pounds of boiling water, which after agitation and subsidence, add to the former liquor. While it is yet hot, or, if it has cooled, having again heated it, drop into it Muriatic Acid as long as effervescence is excited. Then strain it and evaporate, that it may crystallize." The first of these processes is the most easy of execution, the muriatic acid combining with the barytes, and disengaging the carbonic acid with effervescence; the muriate of barytes remaining dissolved, and by evaporation being obtained crystallized. But the native carbonate of barytes being not an abundant mineral production, is not always to be procured: the second process, therefore, is inserted, in which the sulphate, which is a more common fossil, is substituted. In this process, the carbonaceous matter with which it is heated attracts the oxygen of the sulphuric acid ; the sulphur remains united with the barytes. This sulphuret of barytes is dissolved by the water, and freed from any undecomposed sulphate ; but in dissolving, it is at the same time, like other sulphurets with an alkaline or earthy base, partially changed; a portion of its sulphur attracts oxygen from the water, reproducing sulphuric acid, with which a. little barytes unites and is precipitated ; the hydrogen of the decomposed water unites with another portion of sulphur, forming sulphuretted hydrogen, which enters into combination with the remaining sulphuret of barytes, and prevents its farther decomposition. When the muriatic acid is dropped in, it combines with the barytes, disengages the sulphuretted hydrogen, and precis pitates the sulphur. The solution of muriate of barytes, on evaporation, affords the salt crystallized. This process, though a little complicated, is perhaps preferable to any other, as it must afford the barytic salt free from any metallic impregnation; for, if any metallic matter be mixed with the sulphate, being reduced by the charcoal, it will not be dissolved in any subsequent step of the process. Vol. II. 24 SALTS. 178 Solutio muriatis baryta. Solution of Muriate of Barytes, " Take of Muriate of Barytes, one part. Distilled Water, three parts. Dissolve." The muriate of bary tes was introduced by Dr. Crawford as a remedy in scrofulous affections, as has been already stated under the class of tonics, to which it belongs. This saturated solution is designed to afford a preparation of uniform strength,—a circumstance of importance, as from the activity of the medicine its dose requires to be regulated with some care. Five drops are given twice a day, and gradually increased to twenty or more. Carbonas calcis prveparatus, olim Creta Praiparata et Cancrorum Lapilli, vulgo Oculi Cancrorum Prceparati. Prepared Carbonate of Lime, formerly Prepared Chalk, and Prepared Crabs Stones, commonly called Crabs Eyes. " Carbonate of Lime, whether the softer variety, commonly named Chalk, or the harder, called Crabs Stones and Crabs Eyes, after being rubbed to powder in an iron mortar, and levigated with a little water on a porphyry stone, is to be put into a large vessel. Water is to be poured upon it, and after the vessel has been frequently agitated, it is to be poured off, loaded w ith the fine powder. On the water remaining at rest, a subtile powder subsides, which is to be dried. The coarse powder which the water could not suspend, is to be again levigated, and treated in the same manner." The same directions nearly are given for the preparation of chalk, by the London College ; the crabs claws and concretions they have rejected, retaining in place of them, as purer than the chalk, Prepared Shells, the process for obtaining which has been already given (page 10.) The directions given by the Dublin College for the preparation of chalk are also similar ; and they have likewise admitted Prepared Oyster Shells, and Prepared Egg Shells, (Ovorum Testae Praeparatae, Ostrearum Testae Praeparatae,) these being prepared as chalk. Chalk is a native carbonate of lime, seldom perfectly SALTS. 179 pure, but containing often portions of argillaceous and siliceous earths. The crabs stones are concretions found in the stomach of the river craw fish, (Cancer Asticus). They are collected when the animal is in a putrid state, are washed and dried. They have the advantage of being free from any gritty particles, and form therefore a smoother powder. They consist of carbonate atid phosphate of lime, with a portion of gelatin ; the proportion of carbonate being about seventy, of phosphate ten or twelve. The shells are of similar composition ; but for all these there is generally substituted in the shops merely chalk prepared with more care, and having a little gelatin diffused through it. They are used as antacids. Potio carbonatis calcis, olim Potio Cretacea. Potion of Carbo nate of Lime. " Take of Prepared Carbonate of Lime, an ounce ; Refined Sugar, half an ounce ; Mucilage of Gum Arabic, two ounces. Rub them together, and then add gradually, Water, two pounds and a half ; Spirit of Cinnamon, two ounces. Mix them." This is similar to th'eohalk mixture of the other Pharmacopoeias, already noticed, and is merely a convenient form for exhibiting carbonate of lime. Creta pr.ecipitata. Precipitated Chalk. Ph. Dub. " Take of solution of Muriate of lime, any quantity. Add to it, of Carbonate of Soda, dissolved in four times its weight of warm distilled water, as much as may be sufficient to precipitate the-chalk. Render the precipitate pure, by allowing it to subside three times, and washing it each time with a sufficient quantity of water. Then collect it, and dry it on a chalk stone or bibulous paper. In this process, the muriate of lime is decomposed by double affinity, the muriatic acid being attracted by the oda, and the carbonic acid combining with the lime. It affords a pure carbonate of lime, but is scarcely of SALTS. 180 sufficient importance to be received as an officinal preparation. Calx. Lime. Ph. Lond. " Take of Limestone, a pound. Bruise it into small yjieces and calcine these in a crucible with a very strong fire for an hour, or until the carbonic acid is entirely expelled, so that acetic acid, when added, shall not disengage any bubbles of air. In the same manner, lime may be prepared from shells, after these have been washed in hot water, and freed from their impurities." There is little advantage in the introduction of this process ; lime prepared on the la ge scale, for the numerous uses to which it is applied, being sufficiently pure for any medicinal purpose, especially as, when it is internally administered, it must always be given in solution ; and in the state in which it is usually met with, it impregnates water just as strongly as lime in its purest state. Aq.ua calcis. Lime Water. (Liquor Calcis, Ph. Lond. —Aqua Calcis, Ph. Dub.) " Take of lime recently prepared, half a pound ; Put it into an earthen vessel, and sprinkle upon it, four ounces of water, keeping the vessel closed while the lime becomes hot, and falls into powder ; then pour on it twelve pounds of water, and mix them by agitation. After the lime has subsided, repeat the agitation; and do so about ten times, keeping the vessel always shut, that the free access of the air may be prevented. Let the water be strained through paper, interposing between the filter and the funnel glass rods, that the water may pass through as quickly as possible. Let it be kept in tottles well stopt." Lime is sparingly soluble in water; not more than being dissolved, at 60°. Yet, notwithstanding this small quantity, the water has a strong styptic taste, and changes the vegetable colours to a green. The caution to exclude the air in this process, arises from the sup- SALTS. 181 position that the lime would combine rapidly with the carbonic acid of the atmosphere. After the solution is strained, it is at least necessary that it should be kept in vessels well stopt. Lime water is the form under which lime is always used internally. It is employed as a tonic, astringent, and antacid in dyspepsia, chronic diarrhoea, and leucorrhcea. Its dose is from one to two pounds daily. Aq.ua calcis composita. Compound Lime Water. Ph. Dub. " Take of Guaiac Wood in shavings, half a pound ; Liquorice Root cut and bruised, an ounce : Bark ot Sassafras bruised, half an ounce; Coriander Seeds, three drachms ; Lime Water, six pints. Macerate them without heat for two days, and strain." The lime water can derive very little additional power from these ingredients, and they, on the other hand, must have their powers very imperfectly extract ed. The preparation is one, therefore, which can have little activity. Solutio mukiatis calcis. Solution of Muriate of Lime. (AquaMuriatis Caki-s Ph. Dub.) " Take of Pure Carbonate of Lime (namely, White Marble,) in small pieces, nine ounces; Muriatic Acid, sixteen ounces ; Water eight ounces. Mix the acid with the water, and add gradually the pieces of carbonate of lime. The effervescence being finished, digest for an hour. Pour off the liquor, and reduce it by evaporation to dryness. Dissolve the residuum in its weight and a half of water, and strain." The muriatic acid combines with the lime, and disengages the carbonic acid. To remove any superfluous acid, and obtain a solution of uniform strength, the s< lid salt is obtained by evaporation, and is then dissolves in a fixed proportion of water. The solution of muriate of lime has been recommended as a tonic, similar, and not inferior to the muriate of barytes. The dose is from fifteen to twenty grains of the dried salt, or thirty drop? 5 of the solution. SALTS 182 Carbonas magnesije, olim Magnesia Alba. Carbonate of Magnesia. " Take of Sulphate of Magnesia, Carbonate of Potash, of each equal weights. Let them be dissolved separately in twice their weight of warm water, and either strained or otherwise freed from impurities. Then mix them, and immediately add eight times their weight of boiling water. Boil the liquor for a short time, stirring it, then allow it to remain at rest, until the heat be diminished a little, and strain it through linen, on which the carbonate of magnesia will remain. Wash it with pure water, until it be perfectly tasteless." In this process there is a mutual decomposition of the salts, the sulphuric acid of the sulphate of magnesia combining with the potash of the carbonate of potash, and the carbonic acid uniting with tiie magnesia. The use of adding the boiling water, and boiling the liquor, is, partly to dissolve the sulphate of potash, which is a salt sparingly soluble, and partly to prevent a species of crystallization which the carbonate of magnesia would undergo, rendering it gritty, and tlms gi ve it a smoothness which it has not when this precaution is not observed. Carbonate of magnesia, however, is generally prepared on a large scale from the Bittern, or liquor remaining after the crystallization of muriate of soda from sea-water, which is principally a solution of muriate of magnesia. This is decomposed by carbonate of potash, or sometimes by an ammoniacal carbonate, and there are some niceties of manipulation requisite to give it the whiteness, lightness, and smoothness, which are valued as marks of its goodness. Hence it is superior in these qualities to what it would be were it prepared by the above process on a small scale. Carbonate of magnesia, properly prepared, is nearly insipid; it is extremely light, white, and smooth to the touch ; is insoluble in water. It consists of from 45 to 55 of magnesia, from 25 to 48 of carbonic acid, and from 15 to 30 of water. What appears to be the neutral carbonate, obtained in crystals by mixing the saline so- METALLIC PREPARATIONS. 183 lutions without applying heat, consists of 25 of magnesia, 50 of acid, and 25 of water. The common preparation is therefore a sub-carbonate. It is given as an antacid in a dose from a scruple to a drachm, and usually produces at the same time a laxative effect. Magnesia, olim Magnesia Usta. Magnesia. " Let Carbonate of Magnesia be exposed in a crucible to a red heat, for two hours. Then preserve it in glass phials well stopt." By the heat thus applied, the carbonic acid of the carbonate, and a considerable portion of its water, are expelled, and the pure magnesia remains. It loses about half its weight. A smaller quantity, therefore, of the pure magnesia, will produce the same effect as a larger of the carbonate. It is preferred to the latter, both from this circumstance, and also, where, from the abundant acidity on the stomach, flatulence is occasioned by the disengagement of carbonic acid when the carbonate is employed. CHAPTER XX. METALLIC A.—METALLIC PREPARATIONS. Metals are distinguished by their opacity, brilliancy, and* density. They are fusible and volatile at very different degrees of heat; and at various temperatures they combine with oxygen, forming oxides, and, in two or three cases, compounds possessed of acid properties. The metals used in medicine are, Silver, Quicksilver, Copper, Iron, Lead, Tin, Zinc, Bismuth, Antimony, and Arsenic. Metals in their pure state being insoluble in the animal fluids, can scarcely exert any action on the system. Tin, by a mechanical action, is supposed to have an 184 METALLIC PREPARATIONS. anthelmintic power: some of the others, as iron, copper, and lead, have been supposed to be capable of being acted on by the gastric fluids, so as to produce certain effects; but in general they must be combined with other agents to render their action powerful and certain ; and it is their preparations only that are used in medicine. The general changes which metals are made to undergo, to fit them for medicinal purposes, are, combining them with oxygen, and farther, combining the oxides thus formed with acids. In general, it is true, that the metal is more active as a medicine, the more highly it is oxidated, though to this there are some exceptions ; and its activity is still farther increased by eombination with an acid. In general also, where the metal is combined with an acid, it is more certain in its operation than where it is merely oxidated, as the activity of the oxide may be influenced by the state of the stomach with respect to acidity; and, besides, uniformity of composition is in general more easily attained in the saline compound than in the oxide alone, and its state of aggregation has usually, from its solubility, less influence on its action. The metallic preparations form some of our most important remedies. They are those most liable to uncertainty in their operation, from variations in the processes to which they are subjected: they are at the same time those which, from their activity, it is necessary to have least variable in strength. The principles, therefore, which regulate their combinations, so far as these are connected with their pharmaceutic preparation, are highly important; and as this subject has not been much illustrated, and errors with regard to it are not unfrequent, I have thought it necessary to consider it at some length, before proceeding to the individual preparations. The simplest form of combination in which metalsare given, is combined with oxygen, or in the state of oxide. In this state they act with more or less power on METALLIC PREPARATIONS. 185 the living system. Their oxidation is generally effected by the action of atmospheric air, assisted by heat, sometimes by deflagration with nitre, and sometimes also by acids, the acid being afterwards abstracted by the action of a substance exerting an affinity to it. The principal objection to this form of preparation is the uncertainty to which it is liable in the uniformity of its composition. Every metal, in exerting an affinity to oxygen, is capable of combining with that principle in different proportions ; and its power of acting on the living system in common with all its qualities, is much influenced by the quantity with which it is combined. Now, the degrees of oxidation of which a metal is susceptible are numerous, and, there is much reason to believe, are even indefinite, from the minimum to the maximum. The reverse of this opinion has indeed been maintained, and it has been supposed that metals are capable of undergoing only certain fixed degrees of oxidation. But the opposite conclusion appears to be more just. If we take, for example, black oxide of manganese, and expose it to heat, part of its oxygen is expelled; and this is more or less, according to the degree of heat applied : in this decomposition there are no fixed stages in the decomposition, where oxides of a certain uniformity of composition, or with a determinate proportion in oxygen, are obtained; but there is a series perfectly indefinite, from the perfect black oxide to that which approaches nearest to the metallic state. Six oxides of antimony have been described, and there is probably a greater number. The only case in which oxides of uniform and determinate composition can be expected to be obtained, are where they are formed under circumstances which establish a perfect uniformity in the process. Thus, if a metal be oxidated by the atmospheric air, exactly at the point at which it melts, as that point is uniform, or always the same, the oxide will likewise be uniform ; and for the same reason, if an oxide is formed at the vaporific point, it will be always of the same composition. ' Vol. II. 25 186 METALLIC PREPARATIONS. But where such a uniformity of external circumstances does not exist, the degree of oxidation may be variable, and, there is every reason, both from facts and from the laws of chemical affinin to believe indefinite This consideration ought to establish a rule in Pharmacy, w hich has unquestionably been too much neglected The opinion having been ad pted, that the metals are susceptible only of few and determinate degrees of Oxidation, the conclusion has been too hastily adopted, that even with considerable variations in the process, or by processes extremely dissimilar, the ultimate product will be the same. There is every reason to believe that, this is incorrect; and hence, when a process for the preparation of any metallic oxide has once been established, and practitioners have become accustomed to its powers and strength, the process ought not to be varied or changed, from he idea of some trivial improvement; as an alteration of circumstances, apparently of little importance, may give rise to a very important change in the result. And it is nearly demonstrable, that the oxides of a metal formed by different processes, as, for example, by a process conducted in the humid way, or by one with the application of heat, cannot be precisely the same. The other form of preparation under which metals are administered, is that in which the metallic oxide is combined with an acid. Compounds*of this kind arc generally more active than those in which the metal is merely oxidated. 'The acid perhaps imparts an additional activity, and the compound being generally more or less soluble, while the oxides are usually insoluble, the lormer must, from this cause, act more powerfully on the stomach, and be more readily received into the circulating mass. These combinations are generally formed by subjecting the metal to the action of the acid. The acid first yields to it oxygen, either directly, by parting with a portion of what it contains; or by a resulting afftnity, enabling it to attract oxygen from the water which may METALLIC PREPARATTONS. 187 be present, or from the atmospheric air. With the oxide formed in either of these modes, the acid then combines. As a metal can exist in different degrees of oxidation, so it may enter into combination with acids with different proportions of oxygen, and from this circumstance, very important differences in their medicinal powers are established. What preparations can differ more widely than the corrosive muriate, or corrosive sublimate, as it is named, of mercury, and the mild muriate or calomel ? Yet the primary difference between them is in the degree of oxidation of the metal, the proportion of oxygen being less in the latter than in the former. In general, when a metal is acted on by a weak acid, or one much diluted, it forms a compound, in which it is less oxidated than when it has been subjected to the action of a more powerful or concentrated acid. Or if heat has been employed to favour the mutual action, the metal passes to a higher state of oxidation than when it has been dissolved in the cold. It even often happens, that after a metal has been oxidated and combined with an acid, it continues to attract oxygen, either from the acid, or from the atmospheric air,—a circumstance requiring to be attended to in Pharmacy, as giving rise to alterations in metallic preparations. It has been stated, that a metal combines with oxygen in general, not in determinate proportions, but indefinitely. The question naturally occurs, therefore, does this also happen when they combine with acids, or do they enter into such combinations only in certain determinate degrees of oxidation ? No question in Pharmacy can be more important: for, according as one or other of these happens, either uniformity of composition, or much uncertainty may be expected to be found in metallic preparations ; and if the latter be the case, much more attention will be required, than might be supposed necessary in establishing a strict uniformity in the processes by which these preparations are formed. METALLIC PREPARATIONS. 188 In general, it appears, that the acid, by the energy of the affinity it exerts, has a very powerful effect in rendering the degree of oxidation determinate, and that these combinations, are, therefore, usually established with uniform proportions. We have an example of this in the two muriates of mercury. In each of these the metal is in a certain state of oxidation, and whatever process be followed, no intermediate combination appears to be formed. At the same time, it must be admitted, that the degree of oxidizement of the metallic oxide, in combining with the metal, appears also to be sometimes indefinite. Thus, in crystallizing a solution of iron in dilute sulphuric acid, the crystals which are first formed are of a pale green colour ; those formed by a second or third evaporation are deeper, and there remains a liquid incapable of crystallizing. In all these there are different states of oxidation. In like manner, in the solution of mercury in nitric acid, the acid may exist in a number of different degrees of oxidation, according to the manner in which the solution has been performed, and these solutions will give rise to very diff erent compounds in the decompositions and new combinations to which they may be subjected. Another source of uncertainty in the composition of the metallic salts, is, that the metallic oxide can combine with various and apparently indefinite proportions of acid. We can have the compound with the acid and metallic oxide combined in those proportions which give rise to neutralization, but we can have it also with various degrees of excess of acid, or excess of base ; and each of these will give a preparation different in power, and liable to be very differently affected by other chemical agents. This is in particular often displayed in preparing metallic compounds by the medium of acids. From the uncertainty to which the oxidation of metals, by the application of heat, is liable, it has frequently been proposed to obtain the product in the humid way, the metal being dissolved in an acid, and this acid being abstracted after- METALLIC PREPARATIONS. 189 wards by a substance exerting an affinity to it, and the metal precipitated in its oxidated state. But in almost every case these precipitates are not pure oxides, as they have been supposed to be ; they retain a portion of the acid with which the oxide was combined, and are therefore sub-salts. They are sometimes thrown down merely by water, and they then retain a considerable proportion of acid in combination ; and even when subjected to the more powerful action of an alkali, the whole of the acid is not abstracted, the influence of quantity adding so much to the force of affinity, that a portion of it is retained by the oxide. In these precipitations from the decomposition of metallic salts, the composition of the precipitate is frequently rendered still more complicated, from part of the precipitating substance entering into the combination. The influence of the proportions in which a metallic oxide and acid may combine, is shown in another case, —that where, by applying heat, the acid may have its solvent power so far aided, and be from this cause so saturated with the oxide, as to be incapable of retaining the whole of it in solution when diluted. When water is added, therefore to a solution of this kind, a partial decomposition ensues; part of the metallic oxide is precipitated, retaining a portion of acid united with it, forming a sub-salt, while the other portion remains dissolved with a slight excess of acid. Now, if such a solution is to be decomposed by adding a neutral salt with the acid of which the metallic oxide is designed to be combined, the mere water in which the salt is dissolved will at the same time act on the metallic solution, and throw down a quantity of this precipitate, which will mingle with the precipitate formed by the metallic oxide and the acid of the decomposing salt, and will of course modify its powers. Hence, a metallic solution is liable to afford, when decomposed, a very different product, both from the different states of oxidation in which it may hold the metal dissolved, and the different proportions of oxide with which the acid may be combined. 190 METALLIC PREPARATIONS. Metallic preparations, it is thus obvious, are liable to considerable uncertainty of composition; and this suggests the conclusion, that processes with regard to them, once established, ought not to be hastily altered, even in circumstances which may appear trivial. It is equally obvious how important it is, that for every active metallic preparation, the same process should be adopted in every country. The nomenclature of the metallic saline preparations is attended with considerable difficulty, especially in discriminating between the different'salts formed from the same acid, united with the same metal, but existing in different states of oxidation. This difference gives rise to very different medicinal properties, or at least very different degrees of activity, and renders it necessary, therefore, that the names ought to be so far distinct, that the one salt cannot be mistaken for the other. Now, the chemical nomenclature is, with regard to this case, defective, and it is difficult to render it more precise. The system of nomenclature requires that the name of each compound salt should be derived from the acid and the base of which it is composed, the acid affording the radical of the generic name, the base giving the specific appellation. But the names of the species of metallic salts have been derived, not from the metallic oxide which is strictly their base or the substance in direct combination with the acid, but from the metal itself. We thus speak of sulphate of iron, muriate of mercury, and others, when the salt is actually sulphate of oxide of iron, muriate of oxide of mercury, &c. Did the metal exist always in one state of oxidation as it is combined with the acid, this nomenclature would give rise to no inconvenience. But as it is often in different states of oxidation, the nomenclature is deficient, or something more is required to distinguish between the different salts which, from these different states of oxidation, may be formed from the same metal and the same acid. In the cases which have been hitherto observed, in general, not more than two salts are formed from di- METALLIC PREPARATIONS. 191 versify or * oxidation in the same metal combined with the same acid ; and one method which has been employed to mark their distinction, is to apply the usual generic name to the salt formed from the metal in the low state of oxidation, and to prefix to the same generic name applied to the other salt, iho syllable oxy, as denoting the higher degree of oxidation. Thus we have two muriates of mercury, one containing the metal at a low, the other at a high degree of oxidation, and these, according to this method, would be distinguished, the one by the name of Muriate, the other by that of Oxymuriate of Mercury. But, independent of the objection, that this violates the principles on which the nomenclature is constructed, since the one salt is just as much a muriate as the other ; the syllable oxy is appropriated, in the language of Modern Chemistry, to a different purpose, that of denoting the compounds of an oxygenated acid ; and Oxymuriate of Mercury, a name now sanctioned by the London College, expresses therefore, not a compound of muriatic acid, as the salt actually is, to which it has been improperly applied, but a compound of oxymuriatic acid, which it is not. Besides, as a medical nomenclature, the merely prefixing the syllable oxy to the same term is far from being sufficient to distinguish between salts totally different, and which it is in the highest degree dangerous to confound. Another method likewise employed, is to apply the generic term to the salt formed from the oxide at the maximum of oxidation, and to prefix to the same term applied to the salt at the minimum, the syllable sub; naming, for example, one of the salts of mercury now referred to, Muriate of Mercury, the other Sub-Muriate of Mercury. This has been adopted by the Edinburgh College ; but. it is equally incorrect. The principles on which the modern nomenclature is founded, require that the epithet sub should be appropriated to the names of those salts in which there is a deficiency of acid or excess of base ; the base, however, still being the same as that of the corresponding salt, to the name of which this epithet 192 METALLIC PREPARATIONS. is not prefixed. But in the metallic salts to which this mode has been applied, there is no deficiency of acid, and the base is not the same ; the salt to which the epithet sub is applied may contain less acid than the other, but this is because the oxide, which is its base, requires less for its saturation ; it is altogether a different species, and by the addition of acid, it cannot be converted into the other, which it would be, were it, as the name implies, a Sub-salt. This mode too is liable to the same objection as the other, the merely prefixing to the name common to both, the epithet sub, to distinguish one of them, not being sufficient ly distinctive, where it is of so much importance that they should be distinguished. These two methods also are unfortunately opposed to each other, the usual generic name being applied according to the one mode to the one salt, while, according to the other, it is applied to the other ; thus the term Muriate of Mercury, will, in the one, be employed to denote the salt with the metal in the highest state of oxidation, and in the other, it will be applied to the salt precisely the reverse, —a circumstance which renders the adoption of either method improper. Any nomenclature founded on the supposition of specific degrees of oxidation being established, would be equally improper; for, even supposing them not to be indefinite, which, however, there is every reason to believe they are, the propriety of the appellation in any case would depend on the perfect accuracy of the analysis, and the discovery of a different degree of oxidation with regard to any metal would require the change of the nomenclature of its salts, and, what is still worse, would cause a name, which had been appropriated to one, to be transferred to another. The only mode that appears practicable, is to derive the distinctive appellations of these salts from properties in which they differ. If two salts, formed from the same metal and the same acid, but only in different states of oxidation, differ in colour, as is frequently the case, this affords a ground of discrimination in their names, and PREPARATIONS OF SILVER. 193 it is accordingly sometimes had recourse to. Thus, we speak of the green and the brown sulphate of iron. If the colour be the same in each, which may be the case, then the distinction may be drawn from any other property in which they differ. Thus the two muriates of mercury may be distinguished, the one by the appellation of Corrosive Muriate, the other by that of Mild Muriate. This nomenclature, while it violates no principle, has the advantage, that being founded on the properties of the substances, it is permanent; and as applied to medicinal substances, it has the not less important advantage, that it serves in the more important cases to point out the difference to which it is most essential to attend. If there should be even cases in which there is no difference of properties sufficiently important to afford a distinctive appellation, it would be better to have recourse to the periphrasis expressing the difference in the state of oxidation to discriminate between them, than to employ a nomenclature, neither sufficiently distinctive nor correct. Metals are sometimes employed medicinally, combined with sulphur or with sulphuretted hydrogen When the sulphur is united with the metal itself, the preparation is generally inactive. When the metal is oxidated, and farther combined, either with sulphur or sulphuretted hydrogen, it is more active ; but as the degree of oxidation may be various, and as the affinities exerted by sulphur or sulphuretted hydrogen are not sufficiently energetic to render them definite, these preparations are liable to be variable in strength. Hence few of them are retained. ARGENTUM.—SILVER. Nitras argenti, olim Causticum Lunare. Nitrate of Silver. (Argenti Nitras, Ph. Lond.) " Take of the Purest Silver, extended in plates and cut, four ounces: Diluted Nitrous Acid, eight ounces : Vol. II. 26 PREPARATIONS OF ANTIMONY. 194 Distilled Water, four ounces. Dissolve the silver in a phial with a gentle heat, and evaporate the solution to dryness. The mass being put into a large crucible, let this be placed on the fire, which must be at first gentle, and gradually increased until the matter flow like oil. Then pour it into iron pipes heated and rubbed with grease. Lastly, keep it in a glass vessel well stopt." The silver in this process is oxidated and dissolved by the nitrous acid. By the subsequent fusion, a considerable part of the acid is expelled, so that the product is rather a sub-nitrate than a nitrate of silver. The metal ought to be pure, as in the state in which it is usually met with in commerce it has an alloy of copper, which gives to the preparation a green colour, and renders it more deliquescent. It is, as has already been stated, a powerful escharotic, and has the advantage of being easily applied, and confined, and of acting quickly. It is therefore the one in general use for the common purposes for which the escharotics are employed. ANTIMONIUM.—ANTIMONY. Sulphuretum antimonii prjeparatum, olim Antimonium Prcepavatum. Prepared Sulphuret of Antimony, formerly Prepared Antimony. (Sulphuretum Antimonii Praeparatum, Ph. Dub.) " Let Sulphuret of Antimony be prepared in the same manner as Carbonate of Lime." This preparation is merely levigation, and when the sulphuret of antimony is levigated, it has been supposed to act with more certainty than when given in a coarser powder. It is still, however, very inactive. As a remedy in chronic rheumatism, it has been given in a dose of five or ten grains daily. Oxidum antimonii cum sulphure vitrificatum, olim Vitrum Antimonii. Vitrified Sulphuretted Oxide of Antimony. " Strew Sulphuret of Antimony, rubbed to a coarse powder like sand, on a shallow unglazed earthen vessel. PREPARATIONS OF ANTIMONY. 195 and apply to it a gentle fire, that the sulphuret of antimony may be slowly heated ; at the same time stirring constantly the powder, that it may not run into lumps. White vapours, smelling of sulphur, will arise from it. When these, while the same degree of heat is kept up, cease, increase the heat a little, that vapours may again exhale ; and proceed in this manner, until the powder, raised at length to a red heat, exhales no more vapours. This powder being put into a crucible, is to be tin ited with a strong tire, until it assume the appearance of f used glass ; then pour it upon a heated brass plate." When solid, it has completely the vitreous appearance, is transparent in thin plates, and of a reddith brown colour. In the first srage of this process, the greater part of the sulphur of the sulphuret of antimony is dissipated, and the antimony is imperfectly oxidated. In the second, the heat applied being more intense, the sulphur is more completely expelled, the antimony is more highly oxidated, and the oxide is vitrified. According to Thenard's analysis, this oxide contains 16 of oxygen in 100 parts. Proust has farther shown, that it retains a portion of sulphur combined with it, or, as he states it, a portion of the metallic sulphuret, (about one part in nine of the preparation), and lastly, Vauquelin found, that it always contains siliceous earth, which is discoverable by the gelatinous residuum obtained on evaporation of any saline compound formed from this oxide. The quantity appears to be about 9 or 10 parts in 100 ; it is derived from the earthy matter of the crucible, and probably promotes the vitrification of the oxide. This preparation is extremely harsh, and at the same time uncertain in its operation, and is hence not used but in preparing some of the other antimonials. Oxidum antimonii vitrificatum cum cera, olim Vitrum Antimonii Ceratum. Vitrified Oxide of Antimony with Wax. " Take of Yellow Wax, one part ; Vitrified Oxide of Antimony with sulphur, eight parts. To the wax, melted in an iron vessel, add the oxide rubbed to powder. 196 PREPARATIONS OF ANTIMONY. and roast them with a gentle fire, for a quarter of an hour, stirring constanty with a spatula ; then pour out the matter, which, when it is cold, rub to powder." It is probable, that during this process, the oxide of antimony loses part of its oxygen, from the carbonaceous matter of the wax attracting it, as it diminishes in weight; and it is probable also, that its state of vitrification is changed. It becomes much milder in operation. Though once highly recommended in dysentery, it may be regarded as an obsolete remedy. The dose in which it was given, was from five to fifteen grains, and its principal operation was that of a cathartic, from which probably any benefit received from it was derived. Oxidum antimonii cum phosphate calcis, olim Pulvis Antimoni- alis. Oxide of Antimony with Phosphate of Lime. (Pulvis Antimoniahs, Ph. Lond. Dub.) " Take of Sulphuret of Antimony, rubbed to a coarse powder, Hartshorn Shavings, of each equal parts. Mix and throw them into a wide iron pot, red hot, and stir them constantly until they are burnt into a matter of a gray colour, which remove from the fire, rub to powder, and put into a coated crucible. Lute to this crucible another inverted, in the bottom of which a small hole is drilled ; apply the fire, which is to be gradually raised to a white heat, and kept at this increased heat for two hours. Lastly, triturate the matter, when cold, into a very fine powder." The process given in the Dublin Pharmacopoeia is the same, except that the hartshorn is ordered to be previously boiled to extract from it the gelatin,—a circumstance of little importance, as this gelatin is decomposed by the heat. The London College have unfortunately changed the strength of the preparation, two parts of shavingsof hornbeingemployed to one of sulphuret of antimony- The reasons assigned for this are, that the preparation is brought nearer to the strength of James's powder, for which this is designed as a substitute, and that it is rendered more manageable in its administration. With regard to the first, it appears to be PREPARATIONS OF ANTIMONY. 197 founded on a mistake, as with the enlarged proportion of antimony, a preparation different in the propbrtions of its constituent parts from those of ihe James's powder, as analyzed by Pearson, must be obtained. And though it were just, it was of more importance to preserve an active preparation, now officinal, of the same strength in all the Pharmacopoeias, than to assimilate it to the strength of an empirical remedy. With regard to the other, the powder appears to be just as manageable of the one strength as of the other. This process has been introduced into the Pharmacopoeias, as affording a preparation similar to the celebrated empirical remedy, James's Powder. Nothing more was known with regard to this, than that it was an antimonial, until its analysis was undertaken by Dr. Pearson. He found the genuine powder of James to consist of 43 parts of phosphate of lime, and 57 of an oxide of antimony, part of which was vitrified; and by the above formula, he was able to prepare a powder similar to it in qualities and chemical composition. The theory of the process is sufficiently obvious. During the first stage, the animal matter of the bones is decomposed and burnt out; the sulphur of the sulphuret of antimony is expelled, and the metal is imperfectly oxidated. In the second stage of the process, the metal is more completely oxidated, the oxide is partially vitrified, and is perhaps brought into combination with the phosphate of lime, which is the residuum of the bones. This latter supposition remains, however, uncertain. That portion at least of the oxide which is vitrified cannot be combined with the phosphate; the other perhaps may be in this state of combination, as Dr. Pearson supposed, though Chenevix, from his experiments on the powder, supposed them rather to be merely intimately mixed. He found too, that in the preparation obtained by Pearson's process, more of the oxide of antimony is vitrified than in the genuine James's powder, the proportion in the one being not less than 44 in 100 of the oxide, in the other only 28. PREPARATIONS OF ANTIMONY. 198 Mr. Chenevix has likewise proposed a method of obtaining this preparation in the humid way. It consists in taking equal weights of the white powder precipitated by water, from muriate of antimony, and of pure phosphate of lime, obtained by dissolving calcined bone in muriatic acid, and precipitating the phosphate by ammonia ; dissolving these in as much muriatic acid as may be necessary, with the assistance of a moderate heat, and pouring this solution into ammonia diluted with distilled water. The ammonia combines with the muriatic acid, and the oxide of antimony and phosphate of lime are thrown down intimately mixed. This preparation may be more uniform in composition than that obtained by heat, as, in the latter, variations are liable to be introduced from the different degrees of oxidation of which antimony is susceptible, from the vitrification, and from the volatility of the antimonial oxide; but it cannot be the same compound as the other: it is indeed merely a mixture of sub-muriate of antimony and phosphate of lime. It has appeared, from some trials made of it, to be milder in its operation than the other preparation ; but it would require much more extensive experience, to determine if it has the same medicinal effects. The medical history of these preparations has been already delivered. James's powder has been celebrated as a remedy in febrile affections. It acts as a general evacuant, occasioning sweat, purging, and frequently vomiting; and, by this general action, appears sometimes to arrest the progress of fever, if given at its commencement, or to produce a more favourable crisis. Its dose is five or six grains, repeated every six hours, till its effects are obtained. It has been affirmed, that the preparation obtained by the process of the Pharmacopoeias is not so certain nor so powerful in its operation as the powder of James, eight grains of the former being not more than equal to six of the latter. The difference, if it exist, may be owing to some peculiarity in the process, by which a difference of oxygenation, or of vitrification of the oxide may be occasioned: and, as has been PREPARATIONS OF ANTIMONY. 199 already stated, it does appear that the proportion of oxide vitrified is not the same in the one as in the other. It. remains to be determined, how far the preparation from the proportions, as given now by the London College, differs from the others. Sulphuretum antimonii pr.otash on the sulphuret of antimony is strained, and alowed to cool, it deposites a red-coloured powder, which has been known by the name of Kermes Mineral, and has been much used on the continent. From the analysis of it by Thenard, it appears to be a compound of brown oxide of antimony and sulphuretted hydrogen, with a small portion of sulphur; the proportions being 73 of oxide of antimony, 20 of sulphuretted hydrogen, and 4 of sulphur, the last, as Thenard supposes, being accidental. Trommsdorff attributes the difference between these two preparations to the one essentially containing sulphur combined with the oxide of antimony and sulphuretted hydrogen ; the other not. Thenard ascribes it. rather to a difference of oxygenation, the oxide in the kermes being less highly oxidated than in the other ; but as both can be obtained from the same solution, either as we allow it merely to cool, or as we add sulphuric acid, which cannot change the state of oxidation, this is not probable, while the difference in the proportion of sulphur must, from the nature of the process, necessarily exist; for in the one case, the oxide can be combined only with those portions of sulphur and sulphuretted hydrogen which it can attract, while in the other the sulphur precipitated by the addition of the acid must be also added. The one preparation, the Kermes Mineral, may be distinguished, though not perfectly correctly, by the name of Hydro-Sulphuretum Oxidi Antimonii Rubrum ; the other by that of Hydro-Sulphuretum Oxidi Antimonii Luteum. The quantity of both products, from a given weight of sulphuret of antimony, may be considerably increased by adding a portion of sulphur, and increasing the quantity of alkali, the proportion of PREPARATIONS OF ANTIMONY. 201 sulphur in the native sulphuret not being sufficient to render the whole of the metal soluble, and a quantity, therefore, without this addition, remaining undissolved. These preparations agree nearly in their medicinal qualities, which are similar to those of the other antimonials. They have been used principally as diaphoretics and sudorifics, but are always uncertain in their operation. The dose of the precipitated sulphuret of antimony, as it is named, is five or six grains. Oxidum antimonii cum sulphure per mtratem potassae, olim Crocus Antimonii. Oxide of Antimony with Sulphur, by Nitrate of Potash. " Take of Sulphuret of Antimony, Nitrate of Potash, of each the same weight. Triturate them separately, and, having mixed them well together, throw them into a crucible red hot. The deflagration being over, separate the reddish matter from the white crust, and t ub it to a powder, which is to be frequently washed with warm water, until it remain insipid." During the deflagration, the nitric acid of the nitrate of potash is decomposed, and its oxygen is attracted, partly by the sulphur, and partly by the antimony. The sulphurous acid, which is the principal product of the oxygenation of the sulphur, is in part dissipated, and in part combined with the potash ; and with a little sulphuric acid likewise produced, forms the white crust which is directed to be removed. By the union of another portion of the oxygen with the antimony, a brown or reddish oxide is formed. It appears also that part of the sulphuret of antimony escapes decomposition or oxygenation, and remains combined with the oxide, in the proportion of about two parts to eight; or rather, perhaps, the oxide retains a little sulphur combined with it. The preparation, therefore, is an imperfect oxide of antimony with sulphur or sulphuret of antimony. It is of a brick red colour; what is to be found in the shops is generally of a gray colour, and is usually prepared very improperly, with a diminished proportion of nitre. Vol. II. 27 ' PREPARATIONS OF ANTIMONY. 202 As an antimonial, this preparation is so uncertain ill its operation, that it is never prescribed; it is used in making some of the other preparations of this metal. Murias antimonii. Muriate of Antimony. "Take of Oxide of Antimony with Sulphur by Nitrate of Potash, Sulphuric Acid, of each one pound; Dried Muriate of Soda, two pounds. Pour the sulphuric acid into a retort, adding gradually the muriate of soda and the oxide of antimony, previously mixed. Then distil from warm sand. Expose the distilled matter for some da\s to the air, that it may deliquesce; then pour the liquid part from the impurities." In this mode of forming muriate of antimony, the muriate of soda is decomposed by the sulphuric acid combining with the soda; the muriatic acid disengaged, unites with the oxide of antimony, and the compound is volatilized. It is at first of a soft consistence, and cannot be dissolved by pouring water upon it, the mass of water acting on it, by its quantity, and decomposing it, separating a sub-muriate. But, when left exposed to the air, it slowly imbibes as much water as is sufficient for its solution without decomposition, and then forms a dense heavy liquid of a brown colour. By the addition of water to this, the same decomposition is produced, and sub-muriate precipitated This preparation is unfit for internal use; externally it has sometimes been used as a caustic. Decomposed by potash, it affords an oxide which has been used in preparing the tartrate of antimony. Muriate of Antimony has not directly a place in the London or Dublin Pharmacopoeia; but a process is given for preparing it, with the view of obtaining from it another antimonial preparation,—probably a sub-muriate, though denominated an oxide. PREPARATIONS OF ANTIMONY. 203 Antimonii oxydum. Ph. Lond.—fOxydum Antimonii Nitro-Muri ticum, Ph. hub.) " Take of Sulphuret of Antimony in powder, two ounces; Muriatic Acid, eleven fluid ounces ; Nitric Acid, one fluid ounce. To the acids mixed together in a glass vessel, add gradually the Antimony, and digest them with a boiling heat for an hour : then strain the liquor, and pour it into a gallon of water, in which two ounces of Sub-Carbonate of Potash have been previously dissolved. Wash the precipitated powder, by pouring water frequently upon it, until no acid remain, then dry it on bibulous paper." This is the process given in the London Pharmacopoeia. In the Dublin, only a drachm of nitrous acid is employed, and the liquor obtained by digesting the materials is decomposed, and the precipitate thrown down, by adding to it a gallon of water, without any sub-carbonate of potash. Muriatic acid acts very feebly on antimony, not being capable of communicating to it oxygen directly, and the affinity to this principle not being sufficiently strong as to be able, even when aided by the resulting affinity of the acid, to decompose water. By the addition of nitric acid, the oxidation and solution are more easily effected, the nitric acid yielding oxygen to the metal, and the oxide combining with the muriatic acid. The sulphur of the sulphuret suffers little change. The strained liquor, therefore, is a muriate of antimony, and this is undoubtedly at once the most simple and most economic al method of procuring it. In the subsequent stage of the process, it is decomposed by the addition, according to the one formula, of a weak solution of subcarbonate of potash ; according to the other, by the addition of water. The precipitate thrown down from muriate of antimony by water used to be regarded as an oxide, but it was long ago shown by Rouelle to be a sub-muriate; the water, by its affinity to the acid, abstracting the greater portion of it; but the oside still, in conformity to the law which usually regulates these de- PREPARATIONS OF ANTIMONY. 204 compositions, retaining a portion of the acid combined. If the sub-muriate, after being precipitated, is thoroughly washed with water, and then digested with a solution of potash or sub-carbonate of potash, a considerable portion of this acid is abstracted, though probably not the whole of it; for the influence of quantity on the affinity exerted by the oxide to the acid is always becoming more powerful as the abstraction proceeds, and will cause a part of the acid to be retained. In the method of applying the sub-carbonate of potash directed by the London College, though designed probably to abstract the acid more effectually from the oxide, it is of no advantage in this respect, though it may increase a little the quantity of precipitate. By the agency of the water of the solution the muriate is decomposed, and the sub-muriate thrown down, the liquor above retaining the excess of muriatic acid. This excess of acid the alkali will be spent in neutralizing, and will probably be even insufficient for this ; it will thus be prevented from acting on the precipitate, so as to abstract any of the acid it contains, at least, unless it were employed in much larger quantity than is ordered by the College. The method of applying with effect the quantity they use, would be to precipitate the muriate with water, remove the acidulous liquor above, wash the precipitate and then submit it to the agency of the sub-carbonate, by digesting them with a small portion of water. A considerable part of the acid might then be abstracted. This preparation is not designed for internal administration, but merely for the preparation of other antimonials, and especially of the tartrate of antimony and potash. Tartris antimonii, olim Tartarus Emeticus, Tartrite of Antimony, formerly Emetic Tartar. (AntimoniumTartarizatum, Ph. Lond. — Tartarum Antimoniatum sive Emeticum, Ph. Dub.) " Take of Oxide of Antimony with Sulphur by Nitrate of Potash, three parts ; Super-Tartrate of Potash, four parts; Distilled Water, thirty-two parts. Boil them PREPARATIONS ANTIMONY. 205 in a glass vessel for a quarter of an hour. Strain through paper, and put aside the strained liquor that cry stals may form." This is the process in the Edinburgh Pharmacopoeia. That which has now a place in the Loudon and Dublin Pharmacopoeias is different, principally in the antimonial oxide that is employed. It is thus given in the former. " Take of Oxide of Antimony," (the precipitate from the muriate described in the preceding process,) " two ounces; Super-tartrate of Potash in powder, three ounces; Distilled Water, eighteen fluid ounces. To the water boiling in a glass vessel throw in gradually the antimony and super-tartrate of potash mixed together, and boil for half an hour; then strain the liquor through paper, and boil it down with a gentle heat in a glass vessel, so that while it cools slowly, crystals shall form." The process is the same in the Dublin Pharmacopoeia, except that only two ounces and a half of super-tartrate of potash are used. The excess of tartaric acid in the super-tartrate of potash is capable of combining with a number of the metallic oxides, and of forming ternary compounds. With oxide of antimony, when not too highly oxidated, it unites with facility, forming a combination of this kind, which constitutes the present preparation. As the tartaric acid is saturated, partly by potash, and partly by oxide of antimony, it is not a pure tartrate of antimony, but a tartrate of antimony and potash, and the name given to it in all the Pharmacopoeias is chemically incorrect, and is so without any necessity or advantage. According to the analysis of it by Thenard, it consists of 38 parts of oxide of antimony, 34 of tartaric acid, 16 of potash, and 8 of water. It is liable, however, to van considerably in the proportions of its constituent principles according to the process by which it has been prepared. These processes have been very various, this being the most important of all the antimonials, and having therefore much engaged the attention of chemists. The principal object of their researches has been to obtain 206 PREPARATIONS OF ANTIMONY. an oxide, not too expensive in its preparation, and which shall combine vvith facility with the tartaric acid. The oxide precipitated by potash from muriate of antimony was recommended by Bergman, and employed in the process given in the preceding edition of the Edinburgh Pharmacopoeia, but was liable to the former objection, being obtained by a process somewhat difficult, and therefore expensive, and hence, though ordered by the College, not being employed by the apothecary. They have, therefore, substituted the brown oxide prepared by deflagration of sulphuret of antimony with nitre. This answers sufficiently well, if it has been properly prepared. As met with in the shops, it is, however, almost always unfit for this purpose ; as, from not being prepared with the due proportion of nitrate of potash, it is not sufficiently oxidated. The vitrified oxide is, perhaps, the most unexceptionable: it cannot be in an improper state of preparation ; being prepared on a large scale, it is not expensive, and it is capable of sufficiently saturating the tartaric acid. It was accordingly recommended by Dr. Black. The principal objection to it is, that it contains a portion of siliceous earth, which accompanies the oxide of antimony in its combination with the tartaric acid, and, when the liquor is considerably evaporated, gives to it a gelatinous consistence, and prevents the crystallization. This, however, scarcely forms a just objection, for it is always proper in the crystallization of this salt not to carry the evaporation of its solution too far. The process of crystallization itself appears to produce a division in the prim iples of the combination, the crystals which form first containing more oxide of antimony than those produced by a farther evaporation, and there remaining at length an uncrystallizable liquid, in which there appears to be an excess of potash combined with the acid and a portion of oxide. As the silex, therefore, does not impede the first crystallization, and as any further crystallization ought not to be attempted, its presence can scarcely be regarded as injurious, and the vitrified oxide is still per- PREPARATIONS OF ANTIMONY. 207 haps the best on the whole that can be employed. The oxide or sub-muriate introduced by the London and Dublin Colleges is essentially the same with that recommended by Bergman, but being obtained by a much easier process, is not liable to the same objection. It appears, too, to be more easily dissolved by the tartaric acid than any other. The principal doubt that can be suggested with regard to it is, whether, being a sub-muriate, the muriatic acid enters into the constitution of the salt that crystallizes, and modifies its powers. It is possible that it may, and it is equally possible thai the small quantity of it which is present may remain in combination with the potash in the residual liquor. If the latter be the case, there can be no just objection to its use. Another source of diversity in the strength of this preparation having perhaps a still greater influence than the oxide employed, is the extent to which the solution is evaporated to cause it to crystallize; the farther the evaporation is carried, more of the potash entering into the composition of the crystals, and the crystals obtained by a second crystallization, when this is practised, being from this cause, too, of a different composition from those of the first. Tartrate of antimony and potash crystallizes in small triedral pyramids, which are efflorescent. Its solubility has been variously stated, and appears to vary according to the quantity of antimonial oxide contained in it, from proper preparation. On an average, it is soluble in fifteen parts of water at 60°. According to Dr. Saunders, one ounce of water at 60° dissolves fifty-two grains of the fully saturated salt; while of that generally met with, it dissolves from thirty-two to thirty-five. This affords even a mode of judging of the strength of this preparation. It is very susceptible of decomposition, suffering it not only from alkalis, earths, acids, and a number of ne'itral salts, but even from vegetable infusions and decoctions, the vegetable matter attracting apparently part of the oxygen of the oxide,—decompositions the occurrence of which requires to be guarded against in extemporaneous prescription. If kept dissolved in w T ater, 208 PREPARATIONS OF ANTIMONY. it is also decomposed, from the spontaneous decomposition of the tartaric acid. This preparation is undoubtedly superior to the other antimonials, in the certainty of its operation, at least as an emetic, and, from its solubibity, is more manageable with regard to dose. Its medicinal applications have been already noticed. It is given as an emetic in a dose of from one to three grains, dissolved in water; and, in smaller doses, as an expectorant and diaphoretic. Vinum tartritis antimonii, olim Vinum Antimoniale. Wine of Tartrite of Antimony. "Take of Tartrite of Antimony, twenty-four grains; White Wine, one pound. Mix, so that the tartrite of antimony may be dissolved." Antimonial Wine, as it was named, was formerly prepared by macerating white wine on the vitrified oxide of antimony in powder, the tartaric acid of the wine dissolving a portion of the oxide, so that the wine acquired the powers of an antimonial preparation. It was liable, however, to be variable in strength, from the proportion of acid in the wine not being uniform. The present, preparation w as therefore substituted for it. It may be doubted, however, whether it is properly officinal. The salt, dissolved in wine, can indeed be preserved longer without decomposition than when dissolved in water; but, even on long keeping, part of the antimonial oxide is deposited. It is given as an emetic in the dose of one ounce; as a diaphoretic, in a much smaller dose. Liquor antimonii tartarizati, Solution of Tartarized Antimony. Ph. Lond. " Take of Tartarized Antimony, a scruple; Boiling Distilled Water, four fluid ounces; Wine, six fluid ounces. Dissolve the tartarized antimony in the boiling distilled water ; then add the wine." This preparation is of the same strength as the preceding one belonging to the Edinburgh Pharmacopoeia. PREPARATIONS OF COPPER. 209 two grains of the tartrate of antimony and potash being contained in an ounce. The dilution of the wine renders it a little more economical, but it is not improbable may have the disadvantage of admitting more readily of the spontaneous decomposition of the metallic salt. CUPRUM.—COPPER. Ammoniaretum cupri, Olim Cuprum Ammoniacum. Ammoniuret ot Copper. (Cuprum Ammomatum, Ph. Lond. Dub.) " Take of Pure Sulphate of Copper, two parts; Carbonate of Ammonia, three parts. Rub them thoroughly in a glass mortar, until all effervescence is finished, and they unite uniformly into a violet-coloured mass, which being wrapt in bibulous paper, is to be dried, first on a chalk stone, and afterwards with a gentle heat. It is to be kept in a glass phial well stopt." The sulphate of copper is decomposed by the carbonate of ammonia. One portion of ammonia combines with the sulphuric acid; another portion of it unites with the oxide of copper, and the violet-coloured mass which is formed is a mixture of the two resulting compounds ; or, perhaps, what is more probable, the sulphuric acid is in combination with the two bases, forming a ternary compound: the water of the two salts rubbed together, renders the new compound, when it is formed, soft or moist; and the carbonic acid is disengaged with effervescence. The preparation is of a dark-blue colour, which it retains when dried. It has been chiefly employed as a remedy in epilepsy. It is given in a dose of at first half a grain twice a-day, which is gradually and slowly increased to two or three grains, and continued for some time; and for internal administration, it has the advantage, over the salts of copper, of being less liable to excite vomiting. Vol. II. 28 210 PREPARATIONS OF COPPER. Liquor cupri ammomati. Solution of Ammoniated Copper. Ph. Lond. " Take of Ammoniuret of Copper, a drachm; Distilled Water, a pint. Dissolve the ammoniuret of copper in the water, and filtre the solution through paper." This is a simpler mode of obtaining a preparation which has had a place in the Pharmacopoeias, obtained by an indirect mode given in the following formula,, wmich retains its place in the Dublin Pharmacopoeia. Ao.ua cupri ammoniati. Water of Ammoninted Copper. Ph. Dub. " Take of Lime Water, eight ounces; Muriate of Ammonia, two scruples. Prepared Verdigris, four grains. Mix them together, and digest lor twenty-four hours; then pour off the pure liquor. In this indirect mode of combining oxide of copper with ammonia, the lime decomposes the muriate of ammonia, by combining with the muriatic acid, and the disengaged ammonia combines with the oxide of copper of the verdigris or sub-acetate of copper, forming a dilute solution of ammoniureted oxide of copper. It has been applied, diluted with an equal part of water, as a mild escharotic, to remove specks from the cornea, and sometimes, in its undiluted state, as a stimulant and escharotic to ulcers. Solutio sulphatis cupri composita, olim Aqua Styptica. Compound Solution of Sulphate of Copper. " Take of Sulphate of Copper, Sulphate of Alumine, of each three ounces; Water, two pounds; Sulphuric Acid, one ounce and a half. Boil the sulphates in water, that they may be dissolved; then to the liquor strained through paper add the acid." This is merely a combination of powerful astringents. It has been applied topically to check haemorrhage, and largely diluted with water, as a wash in purulent ophthalmia. PREPARATIONS OF IRON. 211 FERRUM.—IRON. Ferri limatura purificata. Purified Filings of Iron. " A sieve being plaeed over the tilings, let a magnet be applied, that the filings may be drawn through the sieve upwards." The iron, from the facility with which it is attracted by the magnet, is by this operation obtained nearly pure, the interposition of the sieve in a great measure preventing particles of other metals, or impurities which are generally mixed with the iron-filings got from the workshops, from being entangled in the cluster which adheres to the magnet. The process, though not always attended to in the shops, is a very necessary one, where iron is to be medicinally employed in this form, or where it is to serve for other preparations of this metal. Oxidum ferri nigrum purificatum, olim Ferri Squamai Purificata:. Purified Blsck Oxide of Iron, formerly Purified Scales of Iron. (OxyJam Ferri Nigrum, Ph. Dub.) " Let the scales of black oxide of iron, which are found at the anvils of the workmen, be purified by the application of the magnet; for the magnet attracts only the more thin and pure scales, leaving those which are larger and less pure." The Dublin College direct that the purified scales shall be farther reduced to a fine powder by levigation, in the same manner as chalk. The scales of iron are the small fragments struck off from the metal when it is heated red-hot. Passingthrough the atmosphere, at this temperature, they are oxidated, but so imperfectly, as to retain their magnetic qmdity, and therefore to admit of this mode of purification by the magnet. They are used only in making some, of the other chalybeate preparations. Carbonas ferri olim Rubigo Ferri Prceparata. Prepared Carbonate of Iron, formerly Prepared Rust of Iron. (Ferri Rubi.i;o, Ph. Dub.) " Purified Filings of Iron are to be frequently mojs* 212 PREPARATIONS OF IRON. tened with water till they fall into rust, which is to be rubbed to a fine powder." During exposure to air and moisture, iron is oxidated, and this oxide is found to be combined with carbonic acid, absorbed probably from the atmosphere. As a chalybeate it is rather more active than the pure metal, and more mild than the other saline combinations of iron. Its dose is from 10 to 20 grains. In a large dose it is liable to occasion uneasiness at the stomach. Carbonas ferri Precipitated Carbonate of Iron (Ferri Carbonas, Ph. Lond. Dub.) " Take of Sulphate of Iron, four ounces ; Carbonate of Soda, five ounces; Water, ten pounds. Dissolve the sulphate of iron in the water, then add the carbonate of soda, previously dissolved in as much water as may be necessary, and mix them well together. Let the carbonate of iron, which is precipitated, be washed with water, and afterwards dried." On mixing the solutions of carbonate of soda and sulphate of iron, the soda aitracts the sulphuric acid; the carbonic acid combines with the oxide of iron ; the sulphate of soda remains in solution ; the carbonate of iron is precipitated. It is to be remarked, however, with regard to this, and all the saline combinations of iron, that the metal enters into them in different states of oxidation, and thus produces very different salts. There is one oxide, the black, nearly at the minimum, containing, according to Lavoisier's estimate, 27 of oxygen in 100, which forms one order of salts ; there is another, the red oxide, at the maximum, which, according to Proust, contains 0.48, which is the base of another series of saline compounds, and between these, are probably also intermediate combinations. In the present process, the sulphate of iron which is employed containing the metal in the low state of oxidation, it is this oxide which combines with the carbonic acid ; but the compound attracts very rapidly oxygen from the atmospheric air, so as to pass to a higher state of oxidation, and the precipitate PREPARATIONS OF IRON. 213 of carbonate of iron, in washing and drying, changes its colour, from this cause, from a dark green to a reddish brown. It differs ultimately therefore, in little from the rust of iron, except that it may be somewhat purer. Carbonate of iron, containing the metal at a low state of oxidation, is a mild and not inactive preparation, preferable to the carbonate or rust, in which the iron is in a higher state of oxidation, as sitting easier on the stomach. The formula of Griffith, which has been highly celebrated as a chalybeate, it has already been remarked, is a preparation of this kind; and as introduced into the London Pharmacopoeia, under the name of Mistura Ferri Composita, has been already considered, (p. 25.) It is an extemporaneous preparation (in which only it is obtained at the low state of oxidation) that it ought to be used; and it has probably little advantage over the common rust of iron in the state in which it is obtained by the present process. Sulphas ferri, olim Vitriolum Viride. Sulphate of Iron. (Ferri Sulphas, Ph. Lond Dub.) " Take of Purified Filings of Iron, six ounces ; Sulphuric Acid, eight ounces; Water, two pounds and a half. Mix them; and the effervescence being over, digest for a short time in a sand-bath; then strain the liquor through paper, and, after due evaporation, put it aside that crystals may form." Iron decomposes water very slowly at a low temperature, but when aided by the action of sulphuric acid the decomposition goes on rapidly. The effect in this case may be ascribed to the concurrent affinities of the iron to oxygen, of the acid or rather the base of the acid to oxygen, and of the acid to iron. These co-operating prevail over the single affinity of the oxygen to the hydrogen of the water: the water therefore is decomposed: its oxygen, the iron, and the acid unite, and the hydrogen is disengaged in the elastic form. The iron in this combination is at a low state of oxidation, the minimum nearly; and the salt which it forms is the Green Sulphate PREPARATIONS OF IRON. 214 of Iron, so named, to distinguish it from the Red Sulphate, in which the metal is more highly oxidated. This green sulphate is prepared for the various purposes to which it is applied in the arts, on a large scale, by exposing the native sulphuret of iron to air and moisture; but, by the present process, it is obtained in a purer state, and titter therefore for medicinal use. Its crystals are of a light green colour; the residual liquor, by a second evaporation, affords crystals of a darker green, in which the metal appears to exist more highly oxidated. In the shops there is often substituted for this salt the common green vitriol, purified by a second crystallization, a little acid having been added to the solution, to dissolve any excess of oxide. Sulphate of iron is one of the most active preparations of the metal. Its medium dose is from three to five grains. Sulphas ferri exsiccatus. Dried Sulphate of Iron (Sulphas Ferri Exsiccatum, Ph. Dub.) " Take of Sulphate of Iron, any quantity. Heat it in an uilglazed earthen vessel, on a gentle lire, until it becomes white and perfectly dry." This is merely the sulphate of iron freed from its water of crystallization by the application of heat. It is not medicinally employed, but has a place in the Pharmacopoeia from being used in one or two pharmaceutical preparations. Oxidum ferri rubrum. Red Oxide of Iron. (Oxidum Ferri Rubrum. Ph. Dub.) " Let dried Sulphate of Iron be exposed to a violent heat, until it is converted into a red coloured matter." By an intense heat, sulphate of iron is decomposed ; its acid is partly expelled, and in part suffers decomposition, being ev olved in the state of sulphurous acid ; the metal at the same time becomes more highly oxidated. The red oxide is the residuum. To free it more completely from any adhering acid, the Dublin College PREPARATIONS OF IRON. 215 order it to be washed with water. It is scarcely medicinally employed, but is used in some pharmaceutical preparations. Tinctura muriatis ferri. Tincture of Muriate of Iron. (Tinct. Muriatis Ferri, Ph Lond. Dub.) " Take of the Purified Black Oxide of Iron, in powder three ounces ; Muriatic Acid about ten ounces, or as much as may be sufficient to dissolve the powder. Digest with a gentle heat, and, when the powder is dissolved, add as much alcohol as that there shall be of the whole liquor two pounds and a half." The process, as given by the London and Dublin Colleges, differs in the rust or carbonate of Iron being employed, and in the proportions being somewhat different. The following is the formula in the London Pharmacopoeia : " Take of Carbonate of Iron, half a pound ; Muriatic Acid, a pint; Rectified Spirit, three pints. On the carbonate of iron, in a glass vessel, pour the muriatic acid, and agitate them occasionally lor the space of three days. Put the liquor aside, that the impurities may subside, and having poured it off, add the spirit." In the Dublin Pharmacopoeia, three pounds of muriatic acid are poured on half a pound of rust of iron; after digestion, the liquor is reduced by evaporation to a pound, and three pints of rectified spirit are added to it. It must therefore be stronger than the other. Iron, in combining with acids, it has already been remarked, unites with them in different degrees of oxidadaiion;and when at the two extremes, or the minimum and maximum, forms with the same acid very different salts. This is well displayed in its combination with muriatic acid. When metallic iron is dissolved in the acid, the solution is of a pale green colour, and affords crystals of a similar colour on evaporation. This salt is soluble in water, but is insoluble in alcohol. When the red oxide or the carbonate is dissolved in the acid, the solution is of a yellow colour ; it is not crystallizable, but by evaporation is reduced to a deliquescent mass : it is soluble PREPARATIONS OF IRON. 216 in water, and is abundantly soluble in alcohol. Of course, it must be this salt which forms the basis of the tincture formed by the present process. In the process, as performed according to the formula of the Edinburgh Pharmacopoeia, the black oxide which is employed combines with the muriatic acid, and during the solution acquires more oxygen, principally from a partial decomposition of the water, which is promoted by the heat applied. The muriate of iron, in which this more perfect oxide is contained, is soluble in the alcohol, diluted as it is by the water of the acid ; yet even with this, the metal is scarcely sufficiently oxidated to form the salt, which is entirely soluble in alcohol. The tincture formed is of a pale green colour,; and it even sometimes happens, that on adding the alcohol to the solution of iron, a great part of the salt is precipitated in crystalline grains. But in a short time, from exposure to the air, oxygen is absorbed, the colour deepens to a yellow, and the precipitate is dissolved. In the process given in the other Pharmacopoeias, the metal is submitted to the action of the acid in a higher state of oxidation ; and the compound is at once formed, which is soluble in alcohol. It may therefore be supposed to be preferable, as there is some risk of the other not being properly prepared, from the tincture being perhaps poured off from the precipitate, instead of being allowed to remain over it until it is dissolved. It appears, however, that the metal may be too highly oxidated to remain in combination with the acid, this tincture always depositing a sediment of oxide when long kept, and this is more liable to happen when the metal is even at first in a highly oxidated state. This tincture is a very grateful preparation ; the alcohol appears to suffer some chemical change from the aciion of the acid and the metallic oxide, the odour becoming etherial. It is a preparation also highly active. It is given in the diseases in which iron is employed, in a dose from ten to twenty drops, largely diluted with water, or, what is more grateful, in wine. If it produce irritation at the stomach, as it is liable to do from its activity, the dose must be diminished. PREPARATIONS OF IRON. 217 The Dublin College have inserted another tincture of muriate of iron, under the name of Tinctura muriatis FERRI cum oxido rubro. It differs in little from the other tincture which they have admitted, in which the rust or carbonate is dissolved by the acid, but in being prepared from the red oxide, and must be regarded as altogether superfluous. Murias ammonia et ferri, olim Flores Martiales. Muriate of Am- monia and Iron. (Ferrum Ammoniatum, Ph. Lond. —Murias Ammoniae et Ferri, Ph. Dub.) " Take of Red Oxide of Iron, washed and again dried, Muriate of Ammonia, of each equal weights. Mix them well together, and sublime." The London College order Carbonate of Iron. Oxide of iron decomposes muriate of ammonia, by attracting the muriatic acid, and in the present process, this decomposition takes place, ammoniacal gas being exhaled. But from the proportions of the substances employed, part of the muriate of ammonia escapes decomposition, is sublimed by the heat applied, and elevates with it part of the muriate of iron that had been formed; or rather, perhaps, the oxide of iron enters into combination with the acid and part of the ammonia, forming a triple compound. Whichever of these is the result, the process is an unscientific mode of obtaining a muriate of iron : the preparation, too, has been found uncertain in strength, more of the muriate of iron being sublimed, according as the heat is applied strongly and quickly ; and, accordingly, it has now fallen into disuse. It was principally employed as a remedy in rickets, in the dose, to children, of two or three grains. It is in crystalline grains, of a yellow colour, and somewhat deliquescent. Tinctura ferri ammoniati. Pharm. Loud. " Take of Ammoniated Iron, four ounces: Proof- Spirit, one pint. Digest and strain." Vol. II. &9 PREPARATIONS OF IRON. 218 This solution of the preceding compound is an unnecessary preparation, as it differs little from the tincture of muriate of iron, and must be less certain with regard to strength. Ferrum tartarisatum. Tartarised Iron. Ph. Lond. " Take of Iron, one pound ; Super-Tartrate of Potash, in powder, two pounds; Distilled Water, one pint. Rub them together, and expose the mixture to the air in an open glass vessel for eight days ; then dry it by a sandbath, and rub it into a very fine powder. To this, having again added a pint of water, put it aside for eight days, then dry it, and rub it into a powder." By exposure to air and moisture, the iron is oxidated, and its oxide combines with the excess of acid in the super-tartrate of potash, a triple salt resulting, composed of potash, oxide of iron, and tartaric acid. By repeating the trituration and exposure to the air in a humid state, the oxidation of the iron is rendered more complete. The Dublin College give the following formula, by which the saline combination is rendered still more perfect : Tartarum ferri. Tartar of Iron. Ph. Dub. 11 Take of Carbonate of Iron, half an ounce ; Crystals of Tartar in fine powder, one ounce ; Distilled Water, a pint. Boil them together in a glass vessel, over a slow fire, for an hour, and filtrate the liquor through paper. After it has cooled, and has been filtrated a second time, evaporate it until a pellicle appear on its surface. The liquor, as it cools, will form a saline mass, which is to be reduced to powder, and kept in close vessels." This is the proper tartrate of iron and potash, as much of the oxide of iron of the carbonate, as the free tartaric acid of the super-tartrate of potash requires for saturation, being dissolved, and the ternary compound being obtained by evaporation. Both this, and the less perfect analogous .compound obtained by the preceding process, have been introduced as mild, and, at the same time, PREPARATIONS OF IRON. 219 active preparations of the metal. It is easily soluble in water, and may therefore be given in a state of solution, and considerably diluted, a form in which the saline preparations of iron always prove less irritating. The dose is lrom five to fifteen grains. The preparation obtained by the formula of the Dublin College has not only been employed in the usual diseases in which iron is prescribed, but has also been highly recommended as a remedy in dropsy, from the combination of its tonic with a diuretic power. vinum ferri. Wine of Iron. Ph. Lond. (Vinum Ferri, Ph. Dub.) " Take of Iron Filings, two ounces ; Wine, two pints. Mix them together, and put aside for a month, shaking them frequently ; ihen strain through paper." In the process given by the Dublin College, four ounces of iron wire cut, are mixed with four pints of Rhenish white wine ; the iron being first sprinkled with a little of the wine until it is covered with rust, the remaining wine being then digested on it for seven days, and afterwards strained. The tartaric acid of the wine contributes to the oxidation of the iron, and dissolves the oxide ; and in the mode directed by the Dublin College, being aided by the action of the air, the oxidation, and consequent impregnation of the wine with iron, will probably take place to a greater extent. The acidity of the Rhenish wine will likewise contribute to this. Still the preparation must be liable to be variable in strength. It has been given as a chalybeate in a dose of one or two drachms. Acetas Ferri. Acetate of Iron. Ph. Dub. " Take of Carbonate of Iron, half an ounce ; Acetic Acid, three ounces. Digest them for three days, and strain the liquor." In this process, the acetic acid dissolves the iron, and may afford a mild and active chalybeate, probably, how- 220 PREPARATIONS OF IRON. ever not differing much in its operation from the tartrate of iron. But, besides this, the Dublin College have ordered not less than two tinctures of acetate of iron. Tinctura acetatis ferri. Tincture of Acetate of Iron. Ph. Dub. " Take of Acetate of Potash, two ounces ; Sulphate of Iron, one ounce ; Rectified Spirit, two pounds. Rub together the acetate of potash, and the sulphate of iron, in an earthen mortar, until they form a mass of a soft consistence. Dry this with a moderate heat, and when dried, triturate it with the spirit. Digest the mixtute in a phial closely corked for seven days, agitating it frequently. When the impurities have subsided, pour off the clear liquor." Tinctura acetatis ferri cum alcohol. Tincture of Acetate of Iron with Alcohol. Ph. Dub. " This is prepared in a similar manner, from one ounce of Sulphate of Iron, an equal weight of Acetate of Potash, and two pounds of Alcohol " In the action of acetate of potash on sulphate of iron, the greater part of the acetic acid will be combined with the oxide of iron, forming acetate of iron, while the sulphuric acid is united with the potash, so as to form sulphate of potash, at least these binary combinations will be rendered more complete by the action of the alcohol added, sulphate of potash being nearly insoluble in that liquid, while acetate of iron can be dissolved. During the trituration, too, it is probable that the oxide of iron absorbs oxygen from the air, and the salt formed, therefore, will be the one containing the metal at the higher degree of oxidation, and which alcohol more easily dissolves. The tincture may have the advantage over the watery solution of acetate of iron formed by the preceding process, of being less liable to spontaneous decomposition ; but it must be regarded as altogether superfluous to have two tinctures differing probably in little more than in strength, or indeed to have more than one PREPARATIONS OF IRON. 221 form of acetate of iron, if there was even any necessity for its introduction as an officinal preparation, which is doubtful. Liquor ferri alkalini. Alkaline Solution of Iron. Ph. Lond. " Take of Iron, two drachms and a half; Nitric Acid, two fluid ounces; Distilled Water, six fluid ounces; Solution of Sub-carbonate of Potash, six ounces. Pour the acid and the water mingled together on the iron; and when the effervescence has ceased, pour off the liquor while still acid. Add to this gradually, and at intervals, the solution of sub-carbonate of potash, agitating frequently, until the colour, having become of a brownish red, effervescence is no longer excited. Put it aside for six hours, and then pour off the liquor." This is a preparation which has long been known under the name of Martial Alkaline Tincture, and the nature of it is not very well ascertained. The iron is oxidated and dissolved by the nitric acid; and the solution which answers best for its preparation, appears to be that in which the iron is in a low state of oxidation, and in which there is an excess of acid ; this is obtained by the solution being effected slowly, and, when in this state, it is of a pale green colour. On adding the sub-carbonate of potash, the alkali saturates a portion of the acid, and the oxide or rather sub-nitrate is precipitated, but by agitation it is kept suspended, and by the excess of alkali is redissolved, this being accompanied with effervescence from the disengagement of part of the carbonic acid. According to this view, therefore, the liquid is a ternary compound of oxide of iron, nitric acid and potash. It has often been remarked, however, by the chemists, that more of the precipitate is redissolved, when carbonate of potash is employed, than when pure potash is used ; and this would lead to the conclusion that a portion of the carbonic acid is likewise retained in the combination, and probably contributes, by its action on the alkali and the oxide, to maintain the state of solution. On standing, a portion of PREPARATIONS OF QUICKSILVER. 222 nitre, formed from the union of the potash and nitric acid is deposited, from which the clear liquor is to be poured off. As this preparation had nearly or altogether fallen into disuse, it is not obvious why it has been restored. No particular advantage is known to belong to it. From the variable state in which it is obtained, from the operation of very trivial circumstances in conducting the process, it must be liable to uncertainty of strength ; and it has been stated by the older chemists, that on being kept, it deposits much of the iron,—a change very likely to happen from the metal passing to a higher state of oxidation. It appears therefore to be an injudicious preparation, and there is less necessity for it, as the preparations of iron in the Pharmacopoeias are already more numerous than what are required in practice. HYDRARGYRUS.—QUICKSILVER. Hydrargyria purificatus. Purified Quicksilver. " Take of Quicksilver, four parts; Iron-Filings, one part. Rub them together and distil from an iron vessel." Similar directions are given in the other Pharmacopoeias, except that in the Dublin one iron is not ordered, and the distillation of the quicksilver is continued only till threefourths have passed over. The quicksilver of commerce has been supposed to be frequently adulterated with other metals. To obtain it perfectly pure is the design of this process. The addition of the iron-filings renders the distilled quicksilver more bright and mobile, an effect not perfectly explained, but ascribed to the iron retaining combined with it any foreign metal, or any portion of carbon that might have been contained in the quicksilver. But the process is in reality not very necessary; for although quicksilver is easily adulterated, this does not appear to be often practised, what is met with in commerce being in gene- PREPARATIONS OF QUICKSILVER. 223 ral nearly pure. The distillation, too, is rather difficult of execution, from the weight of the quicksilver and the high temperature that requires to be applied. Wherever there is reason, however, to suspect any impurity, the purification by this method ought to be performed. Acetis hydrargyri. Acetite of Quicksilver. (Acetas Hydrargvri, Ph. Dub.) " Take of Purified Quicksilver, three ounces ; Diluted Nitrous Acid, four ounces and a half, or a little more than may be requisite to dissolve the quicksilver ; Acetite of Potash, three ounces; Boiling water, eight pounds. Mix the quicksilver with the diluted nitrous acid 5 and towards the end of the effervescence, digest, if necessary, with a gentle heat, until the quicksilver be entirely dissolved. Then dissolve the acetite of potash in the boiling water, and immediately on this solution, while hot, pour the other, and mix them both by agitation. Then put aside, that crystals may be formed. These being placed in a funnel, wash them with cold distilled water ; and, lastly, dry them with a very gentle heat. " In preparing the acetate of quicksilver, it is necessary that all the vessels and the funnel which are employed should be of glass." Acetic acid, like the other acids, combines with mer- cury in different states of oxidation, and forms salts which are different in their properties. When the metal is in a high state of oxidation, a salt is formed which is acrid and soluble ; when in a lower state of oxidation, the salt obtained is more mild and sparingly soluble. The object of the present process is to obtain the latter of these salts: it may be doubted, therefore, if the application of heat to promote the solution of the mercury is proper, as it causes it, in dissolving, to pass to a too highly oxidated state. It has another disadvantage; that the acid being saturated with oxide, the solution is decomposed by water, and a sub-nitrite is precipitated; and accordingly this happens, when a solution, prepared with the aid of heat, is added to a solution of acetate of PREPARATIONS OF QUICKSILVER. 224 potash. By employing an excess of acid, this is counteracted to a certain extent, and from this circumstance, the process, as given in the Edinburgh Pharmacopoeia, may succeed. But by the solution being effected withou heat, less acid is required ; the process is more econo meal, and is equally successful, the mild acetate being copiously formed. On mixing the two solutions, the nitric acid of the nitrate of mercury combines with the potash of the acetate of potash, while the acetic acid unites with the oxide of mercury. The acetate of mercury remains at first dissolved, but on the liquid cooling a little, it appears in the form of delicate crystals, of a white colour and silvery lustre. Instead of employing boiling water to dissolve the acetate of potash, it is preferable to use only tepid water, as at a high temperature the water is liable to produce a partial decomposition of the acetate, so that it is of a yellow colour from a slight excess of oxide. It is necessary, too, not to continue to wash the salt after it is formed with much water, for a similar partial decomposition takes place, and the crystals become yellow. If this should happen, the brilliantwhiteness is instantly restored by washing them with, a little diluted distilled vinegar, the acetic acid neutralizing the excess of oxide to which the yellow colour is owing. With these precautions, the process, which often fails when they are not attended to, is easily conducted, and the preparation obtained perfectly uniform, and in a proper state. Acetate of mercury crystallizes in small brilliant flakes. It is soluble in hot, and insoluble in cold water. As an antisyphilitic remedy, it is very mild in its operation ; but its effects are not considered as sufficiently permanent to allow of its being relied on in effecting a radical cure. Its dose is a grain, night and morning. PREPARATIONS OF QUICKSILVER. 225 Murias hydkargyri, olim Mercurius Sublimatus Corrosivus. Mu- riate of Quicksilver. (Oxymurias Hydrargyri, Ph. Lond.—Marias Hydrargyri Corrosivum, Ph. Dub.) —Murias Hydrargyri Cor. rosivus. Corrosive Muriate of Mercury. " Take of Purified Quicksilver, two pounds; Sulphuric Acid, two pounds and a half; Muriate of Soda, dried, four pounds. Boil the quicksilver with the sulphuric acid in a glass vessel placed in a sand-bath, until the matter become dry. Mix this when cold in a glass vessel with the muriate of soda; then sublime it in a glass cucurbit with a heat gradually raised. Separate the sublimed matter from the scoria}." The same process is given in the other Pharmacopoeias, rather a larger quantity of sulphuric acid (three pounds) being ordered by the Dublin College, perhaps with advantage, and a smaller quantity (two pounds and a half) of muriate of soda. If this quantity of muriate of soda is sufficient to afford the quantity of muriatic acid requisite to the saturation of the oxide of mercury in the sulphate, the reduction of it from the larger proportion ordered in the other Pharmacopoeias will also be an advantage, as it will render it more easy to apply a due degree of heat in the subliming vessel to the whole mixture. In the first stage of the process, the sulphuric acid, aided by the high temperature, oxidates the mercury, and combines with the oxide; the salt formed being that which contains the metal in a high state of oxidation. This salt, in its dry state, is mixed with muriate of soda, and, by the application of heat, a double decomposition is effected ; the soda attracts the sulphuric acid, and the muriatic acid combines with the oxide of mercury. The muriate of mercury being easily volatilized, is separated from the sulphate of soda by sublimation. The process formerly employed in the preparation of this important mercurial salt, consisted in mixing together sub-nitrate of mercury, muriate of soda, and dried sulphate of iron, and subliming the muriate of mercury, formed by the re-action of these, by the application of a sufficient heat. The present process has been Vol. II. 30 226 PREPARATIONS OF QUICKSILVER. substituted as more simple, and more economical, from the expense of the nitric acid in preparing the sub-nitrate of mercury being avoided. There is some reason to doubt, however, whether, from a given weight of mercury it affords the same quantity of product; a deficiency arising from the sulphate of mercury not containing a sufficient quantity of acid to decompose as much muriate of soda as is requisite to afford the muriatic acid necessary to convert the whole of the oxide of mercury into muriate. The enlarged proportion of sulphuric acid, and diminished proportion of muriate of soda, directed by the Dublin College, are perhaps in this respect useful. This mercurial having long been established in medical practice, has been frequently submitted to chemical analysis. The earlier analysis were necessarily incorrect. The investigation of the composition of this and the other muriate of mercury was some years ago undertaken by Mr. Chenevix, and the relative proportions of their principles determined. It had been supposed by some chemists, that it is a compound of oxide of mercury with oxymuriatic acid ; this supposition, he found no reason to admit; the compound consisting of mercury in a high state of oxidation united with muriatic acid ; the oxide, which is its basis, he concluded, consists of 85 of mercury, and 15 of oxygen; and 100 parts of the salt are composed of 82 of this oxide, and 18 of muriatic acid. Its ultimate principles, therefore, and their proportions, are 18 of acid, 12.3 of oxygen, and 69.7 of quicksilver. Zaboada, from a more recent analysis, has inferred, that the oxide does not contain more than 10 of oxygen in 100 parts, and that 80 of this oxide are combined with 20 of acid. According to this, the ultimate principles and their proportions will be 20 of acid, 85 of oxygen, and 71.5 of quicksilver. Some other chemists have given results nearly the same. The impropriety of the term Oxymuriate of Mercury, given to this salt by the London College, has been pointed out in the observations on the nomenclature of PREPARATIONS OF QUICKSILVER. 227 the metallic salts. Neither is the name Muriate of Mercury, given to it by the Edinburgh College, sufficiently distinctive. In modern chemical writings, this name is even frequently given to the other Muriate of Mercury, in which the metal is at a lower state of oxidation, —a circumstance which must render this as a medical nomenclature extremely hazardous. The name Corrosive Muriate of Mercury is the one which deviates least from the principles on which the system of chemical language is established, and the one which ought to be adopted, considered in relation to its medicinal application, as affording the most marked distinction, and approaching nearest to the appellatiou by which it has been long known. Corrosive muriate of mercury is obtained by sublimation in the form of a dense crystalline mass : when sublimed slowly, it condenses in slender prismatic crystals; and it is obtained in a similar form by crystallization from its watery solution. It is easily soluble in water, requiring 20 pa ts at 60° for its solution, and 2 parts at 212°. ltisstiltmore soluble in alcohol, requiring scarcely 4 parts at 60°. Its taste is acrid and metallic. It changes to a green several vegetable colours; is decomposed by the alkalis and earths, and by a number of compound salts, and likewise by vegetable infusions. It is the most powerful of the mercurial preparations. Its dose cannot safely exceed the fourth of a grain, nor can more than one grain be given in twenty-four hours. As an antisyphilitic remedy it has long been established in practice, and it possesses some advantages. It acts speedily, and its action is more general on the system, or less determined to particular organs ; these advantages have led to its frequent use, especially under the form of various empirical remedies, which have been employed in the treatment of syphilis. They are more than counterbalanced, however, by the occasional violence of its operation, and by the uncertainty which attends it, so that it cannot be relied on in establishing a permanent cure. It is given in the form of solution in water or al- 228 PREPARATIONS OF QUICKSILVER. cohol, the dose being increased from the eighth to the fourth of a grain, night and morning, and mucilaginous diluents being freely taken, to lessen the irritation it is liable to occasion. As the solution has a very disagreeable taste, it is sometimes made into pills with crumbs of bread. In other diseases besides lues venerea, it is occasionally exhibited, particularly in cutaneous affections. Externally, its solution is employed as an escharotic in chancre and venereal ulcers of the mouth ; and a very dilute solution of it has been used as an injection, to excite inflammation in obstinate gleet. Liquor hydrargyri oxymuriatis. Solution of Oxymuriate of Mercury. Pharm. Lond. " Take of Oxymuriate of Mercury, eight grains ; Distilled Water, fifteen fluid ounces; Rectified Spirit, one llmd ounce. Dissolve the oxymuriate in the water, and add the spirit." This formula is designed to afford a form of preparation under which corrosive muriate of mercury may be administered and its dose be easily regulated. An ounce contains half a grain; its dose therefore may be from one to two drachms. Sub-murias hydrargyri, olim Calomelas. Sub-muriate of Quick- silver. (Sub-murias Hydrargyri, Ph. Lond. —Sub-murias Hydrargyri Sublimatum, Ph. Dub.) —Murias Hydrargyri Mitis. Mild Muriate of Mercury. " Take of Muriate of Quicksilver, rubbed to powder in a glass mortar, four ounces ; Purified Quicksilver, three ounces. Rub them together in a glass mortar, with a little water, that the operator may be guarded against the acrid powder which would otherwise arise, until the quicksilver is extinguished. Put the dried powder into an oblong phial, of which it shall fill only one third, and let it be sublimed in a sand-bath. The sublimation being finished, and the phial broken, the red powder at the bottom and the white one about the neck of it are equally to be rejected; the remaking mass PREPARATIONS OF QUICKSILVER. 229 is to be again sublimed, and rubbed into a tine powder, which is lastly to be washed with boiling distilled water." The directions in the other Pharmacopoeias are the same, except that in the London Pharmacopoeia the sublimation is ordered to be twice repeated. This is, perhaps the most important preparation of mercury, both from the certainty of its operation, its mildness, combined at the same time with sufficient activity, and the numerous indications it is capable of fulfilling. The process, by which it is obtained, too, is one that fortunately is little liable to be varied by circumstances, but affords an uniform product. The ultimate result of the process, is to bring a quantity of metallic mercury into combination with the principles of corrosive mercury. In the corrosive muriate, the metal exists in a high state of oxidation, and this oxide is combined with a considerable proportion of muriatic acid. The additional proportion of quicksilver, triturated with it, appears to be quickly oxidated, for it soon loses its metallic form, and the whole is converted into a gray powder. By the application ol the heat, which is necessary to produce sublimation, the combination is rendered complete; the quicksilvei which is added, shares the oxygen of the oxide in the corrosive muriate, and the whole oxide, thus formed, combines with the muriatic acid, which the corrosive muriate contained. It is a general law, with regard to the combinations of acids with metallic oxides, that when the metal is highly oxidated, more acid is required to produce saturation, than when it is in a low state of oxidation. Hence, if the degree of oxidation in any saline metallic compound be reduced, less acid will be necessary to the constitution of the new compound in the neutral state, and this is well displayed in the present combination ; for, although the quantity of base is increased, relatively to the acid, yet as this base is also brought into a lower state of oxidation, the portion of acid appears to be sufficient to produce saturation in the new compound ; it gives no indication of being a sub-salt, has no tendency to combine PREPARATIONS OF QUICKSILVER. 230 with a larger quantity of acid, nor apparently any power of neutralizing any additional proportion; it is of determinate composition, and is obtained in a crystalline form. The product then of this process is a muriate of mercury, in which the metal is in a low state of oxidation, and in which this oxide is combined with a small quantity of muriatic acid. This not inferred merely from the nature of the process by which it is formed, though it is sufficiently established by this; but it is likewise confirmed by its analysis. Mr. Chenevix determined the proportions of its constituent principles, by the same series of experiments by which he investigated the composition of the corrosive muriate. The oxide which is its base, he concluded, is composed of 89.3 of quicksilver, and 10.7 of oxygen; and in 100 parts of it, 88.5 of this oxide are combined with 11.5 of muriatic acid. Its ultimate principles, therefore, are 11.5 of acid, 9.5 of oxygen, and 79 of quicksilver —proportions of oxygen and acid considerably less than what, according to the experiments of the same chemist, enter into the composition of corrosive muriate of mercury. It has already been stated, that the subsequent experiments of another chemist, Zaboada, afford the result, that less oxygen exists in the composition of the oxide, which is the base of the corrosive muriate, than what is assigned by Chenevix; and the same experiments afford a similar result with regard to the oxide which is the base of the mild muriate; but still they establish the same general difference between these two salts, —that in the mild muriate, or sub-muriate as it is named, the metal is less highly oxidated and the oxide is combined with a less proportion of muriatic acid. According to Zaboada, the oxide in the mild muriate contains little more than 5 of oxygen in 100 parts, and the salt itself is composed of 89.4 of this oxide with 10.6 of muriatic acid. Its ultimate principles are 10.6 of acid, 4.4 of oxygen, and 85 of quicksilver. I have already pointed out the impropriety of the PREPARATIONS OF QUICKSILVER. 231 name given by the Colleges to this compound, that of Sub-muriate, which is a violation of the principles on which chemical nomenclature is founded. The compound is not, as the name implies, a Sub-Salt; nor is its relation to the other salt, named Muriate of Mercury, such, that it can by any addition of acid be converted into it. As a medical nomenclature, it is still more objectionable, and the introduction of it is to be regretted, the merely prefixing the syllable sub not being sufficient to guard effectually against the dangerous mistake of confounding it with the other, from which it differs so widely. The name, Mild Muriate of Mercury, is under both points of view preferable, as hns been already explained ; though it will always be safer to prescribe it by the arbitrary name of Calomel, by which it has been long known. The combination, whence the mild muriate of mercury is formed, is scarcely complete at the first sublimation ; a portion of the quicksilver rises on the first application of the heat, and adheres to the portion of muriate condensed on the sides of the vessel, in minute globules ; and a small quantity of unchanged corrosive muriate appears also to be diffused through the mass. The white powder mentioned in the formula of the Edinburgh Pharmacopoeia, as collected in the neck of the matrass, is corrosive muriate, and is to be rejected ; the red powder is oxide of iron, which, when the corrosive muriate is prepared by the medium of sulphate of iron, is diffused through it in minute quantity, but which will not be present when the corrosive muriate is prepared, as is now directed, from sulphate of mercury. To render the combination complete, the sublimed mass is reduced to powder, and is sublimed a second time. The London College order even a third sublimation, and the practice formerly was to sublime it six or seven times. This is, however, altogether unnecessary ; and it has even been ascertained, that at each sublimation a little corrosive muriate is re-produced. After the second sublimation, any globules of quicksilver that may adhere to the mass PREPARATIONS OF QUICKSILVER. 232 are removed ; it is reduced to a tine powder by trituration and levigation with water, and is well washed with water, until the Water pass off tasteless, and according to a test given by the Dublin College, give no indications of precipitation, from adding a few drops of a solution of carbonate of potash. A method has lately been introduced by Mr. Howard, of conducting the sublimation in an apparatus, so constructed, that the vapours are not condensed in the upper part of the vessel, forming a solid mass, but are condensed on the surface of water. The aggregation, whence a certain degree of ductility and hardness arises that renders difficult the levigation of the sublimate, is thus obviated; it is obtained at once, in the state of a fine powder, and any corrosive muriate that may rise with it is abstracted. Mild muriate of mercury in its common form is in a dense cake, which is evidently an aggregate of short prisms: and when formed, in particular, by slow sublimation, these are very conspicuous. It is semi-transparent, has a slight yellowish colour, which is liable to be darkened by light, is somewhat ductile and very heavy, its specific gravity being 7.2. It is less volatile than the corrosive muriate; it appears to be altogether insoluble in water; at least Rouelle has stated, that above 1000 parts of water are required for its solution. When pure it is perfectly insipid. As a mercurial, this preparation is extensively employed, its operation being sufficiently mild, and, at the same time, certain and active, and its use is only limited by the tendency which it has to occasion purging. As a remedy in syphilis, it is given in the dose of a grain night and morning, its determination to the intestines, being prevented, if necessary, by the addition of a littlo opium. It is the preparation which is most usually given in the other diseases in which mercury is employed, as in affections of the liver or neighbouring organs, in cutaneous diseases, chronic rheumatism, tetanus, hydrophobia, hydrocephalus, and in febrile affections, especially those of w arm climates. It is in common use as a PREPARATIONS OF QUICKSILVER. 233 cathartic, either by itself in a dose from five to ten grains, or in a smaller quantity to promote the operation of other purgatives. Its anthelmintic power is justly celebrated. And it is perhaps superior to the other mercurials in assisting the operation of diuretics in dropsy. From its great specific gravity, it ought always to be given in the form of bolus or pill. Sub-murias hydrargyri pr&cipitatus. Precipitated Sub-muriate of Mercury (Sub-murias Hydrargyri Pra?cipitatum. Ph. Dub.) " Take of Diluted Nitrous Acid, Purified Quicksilver, of each eight ounces; Muriate of Soda, lour ounces and a half; Boiling Water, eight pounds. Mix. the quicksilver with the diluted nitrous acid; and, towards the end of the effervescence, digest with a gentle heat, shaking the vessel frequently. It is necessary, however, that more quicksilver should be mixed with the acid than this can dissolve, that the solution may be obtained fully s iterated. Dissolve at the same time the muriate of soda in the boiling water : pour the other solution on this while warm, and mix them quickly together. After the precipitate subsides, pour off the saline liquor, and wash the sub-muriate of mercury, by frequently adding v\arm water, pouring it off after each time the precipitate subsides, until it come off 138101688." In the Dublin Pharmacopoeia, the directions given are nearly the same, seven ounces of quicksilver being digested with five ounces of diluted nitrous acid, for six hours, and the liquor, at the end of this digestion, being made to boil for a short time, then poured off from the undissolved quicksilver, and added to a solution of muriate of soda in warm water. The design of the process is to obtain mild muriate of mercury, the muriatic acid of the muriate of soda combining with the oxide of mercury, and forming this compound, while the nitric acid of the mercurial solution is saturated by the soda: and the advantages supposed to belong to it are, that it is more easily executed, Vol. II. 31 PREPARATIONS OF QUICKSILVER. 234 less expensive, and affords the product in a much finer powder than that obtained by sublimation can be reduced to. It was introduced on the authority of Scheele, and the directions which are given are those which he pointed out. The theory of metallic solutions was, however, in his time imperfectly understood, and the process to afford the proper product ought to be conducted in a very different manner. Scheele was evidently misled by the analogy of dissolving a salt in water, the quantity dissolved being increased by heat; and hence, by aiding the action of the acid on the quicksilver by heat, it appeared to follow, that a larger product would be obtained, and that the acid being thoroughly saturated, the product would be more mild. Two circumstances, however, operate in this case, and give rise to other results. 1st, By digesting or boiling the acid on the metal, the decomposition of the acid is facilitated, and the mercury passes to a more highly oxidated state ; hence, when the solution is added to the solution of muriate of soda, the degree of oxidation being too great to admit of the whole being converted into mild muriate, a portion of corrosive muriate is always formed. It has been observed, indeed, that although in the first stage of the solution much nitric oxide gas is disengaged, indicating a decomposition of the acid to a considerable extent, yet, that after this, an additional portion of quicksilver is dissolved without much effervescence, whence it has been concluded by some chemists, that this portion must receive oxygen from the portion already dissolved, and that the whole therefore will still exist in a low state of oxidation. The degree of oxidation may perhaps be so far reduced in this manner, but the fact is, that the mercury, in the solution thus is still too highly oxidated to be converted entirely into mild muriate when combined with muriatic acid; that a portion of it is always converted into corrosive muriate, and that with a solution so prepared, less muriate of mercury is obtained from a given weight of quicksilver, than from a PREPARATIONS OF QUICKSILVER. 235 solution prepared entirely in the cold. 1 have ascertained this by experiment, the quantity of mild muriate obtained from a solution of one ounce of quicksilver in diluted nitric acid in the cold being a little more than an ounce, while from the same quantity dissolved with the application of heat, the precipitate did not much exceed half an ounce, while the liquor held dissolved much more corrosive muriate than the other. 2dly, When the solution of the quicksilver in the acid is promoted by heat, the acid is so completely saturated with oxide, that the solution is partially decomposed by mere dilution with water, a quantity of sub-nitrate being precipitated. Hence, when such a solution is mingled with the solution of muriate of soda, this decomposition wiil take place to a certain extent, from the operation of the water of the solution, and a quantity of this subnitrate must be mixed with the mild muriate, and must so far modify its powers. These sources of error are obviated by using a solution of mercury prepared in the cold, and with a diluted acid ; and from such a solution carefully prepared, the product, 1 have found, is almost entirely mild muriate, with very little corrosive muriate. The method of conducting the process in this manner is to add the quicksilver in small portions at a time to the nitric acid previously diluted with one part and a half of water, (observing the proportions given in the Edinburgh Pharmacopoeia), and to avoid altogether the application of heat; when the solution is completed, or no more mercury appears to be capable of being dissolved, a little water is to be added, so as to dissolve any part of the nitrate of mercury that may have crystallized ; the clear solution is poured off from the undissolved quicksilver, and is added to the solution of muriate of soda. The precipitate having subsided, is to be carefully washed with water, repeatedly poured on it, to carry off the small quantity of corrosive muriate that is formed. Berthollet has affirmed, however, that even as prepared from a solution of this kind, the precipitate retains in 236 PREPARATIONS OF QUICKSILVER. combination a portion of nitric acid ; probably owing to the circumstance that such a solution must always have an excess of aci!, part of which the precipitate, as it is formed, may attract. The process ought, on every account, perhaps to be expunged from the Pharmacopoeias. It has no advantage, for it is not, as has been supposed, more economical The fineness of the powder is of little importance, for by levigation the sublimed muriate is obtained sufficiently fine for medicinal use; and the process by sublimation gives a product perfectly uniform, while that by precipitation must always be liable to some uncertainty, from being so much influenced by the manner in which it is conducted. If it is ever followed, much attention should be made to washing the precipitate thoroughly, so that not the most minute portion of the corrosive muriate may remain mixed with it The precipitated mild muriate of mercury is in the state of a smooth powder, whiter, and of much less specific gravity than the muriate prepared by sublimation, differences probably depending on its state of aggregation When pure, its medicinal operation must be the same. It has been said, from trials that have been made of it, to be more liable to occasion purging. If this difference exists, it is probably owing to the presence either of sub nitrate of mercury, or of a minute quantity of corrosive muriate. Oxidum hydrargyri cinereum. Ash-coloured Oxide of Quicksilver. (Pulvis Hydrargyri Cinereus, Ph. Dub.) " Take of Purified Quicksilver, four parts; Diluted Nitrous Acid, five parts ; Distilled Water, fifteen parts ; Water of Carbonate of Ammonia, as much as may be sufficient. Dissolve the quicksilver in the acid. Add gradually the distilled water. Then pour on as much of the water of carbonate of ammonia as may be sufficient to precipitate the oxide of quicksilver, winch is to be afterwards washed with pure water and dried." The directions in the Dublin Pharmacopoeia are similar, ex~ PREPARATIONS OF QUICKSILVER. 237 eept that the solution of the quicksilver in the acid is promoted by a gentle heat. The action of ammonia on metallic salts is not perfectly similar to that of the other alkalis. It appears to have a greater tendency to unite with the oxide, and a portion of the acid, so as to form ternary combinations, and from its hydrogen attracting oxygen, it sometimes changes the constitution ot the metallic oxide. These actions-appear to be modified by the state of oxidation of the metallic s ilt, and this is well displayed in the effects it produces in the present process on the nitrate of mercury. If the mercurial solution is in that state in which the metal is highly oxidated, on adding the ammonia, a precipitate is thrown down perfectly white. This was found by Fourcroy to consist of the oxide of mercury, in combination with a portion of acid and of ammonia, its composition, as he determined it, being 68.2 of oxide, 16 of ammonia, and 15.8 of nitric acid. But if the solution contain the metal in a low state of oxidation, the precipitate which is formed is of a dark blue colour approaching to black. This has been supposed to be merely the oxide of mercury that had been combined with the nitric acid, the ammonia combining with the acid, and precipitating the oxide. But an obvious objection to this opinion is, that the precipitate is not the same as that thrown down by potash or soda, but is of a more uniform colour, and darker, a proof that ammonia exerts some peculiar action in its production. According to Fourcroy, who investigated with considerable care these and other saline mercurial combinations, the ammonia, in precipitating the oxide from its combination with the acid, partially de-oxid ites it, the hydrogen of a portion of the ammonia attracting part of the oxygen of the oxide, and reducing it to a still lower state of oxidation, approaching nearly indeed to the metallic state: hence there is at the same time a disengagement of a portion of nitrogen gas in consequence of this decomposition of a part of the ammonia, which when the process is per- PREPARATIONS OF QUICKSILVER. 238 formed in the large way, produces an effervescence, and may be collected. In frequently performing this process, it has appeared to me that this peculiarity of action by ammonia is exerted only when the mercurial solution contains the metal in a state of oxidation intermediate between the minimum and maximum. If care has been taken in preparing the solution, so as to have it with the metal dissolved at a very low degree of oxidation, the precipitate thrown down by potash is as dark in its colour as that by ammonia. But if it be somewhat more highly oxidated, that from ammonia is of a much darker colour, and there appears even a film on the surface, with a lustre approaching to metallic. The theory given by Fourcroy, of the operation of the ammonia, is therefore probably just, though I must add, that any effervescence indicating the disengagement of nitrogen gas is extremely slight, and on a small scale is scarcely apparent. Some chemists have supposed, that the dark gray precipitate contains ammonia. When the precipitate, however, is properly prepared, and thoroughly washed, I have not been able to discover any trace of ammonia in it: when mixed with lime, or with a fixed alkali, no ammonia is exhaled even when heat is applied. If the solution, however, from which the precipitate has been thrown down, has been that in which the metal has been highly oxidated, part of the white triple compound described by Fourcroy will have been formed, and in this case a portion of ammonia is present. In decomposing mercurial solutions accordingly in this state, the precipitate at different stages of the precipitation is various in its colour, being at first gray, and afterwards lighter, and being more or less light as the solution contains the metal more highly oxidated, evidently from the predominance of the white precipitate. But any ammonia derived from this source is foreign to what properly constitutes the gray precipitate. From the circumstances which influence this preparation not having been fully understood, it has been sup- PREPARATIONS OF QUICKSILVER. 239 posed difficult to obtain it uniform; nor are the directions in the Pharmacopoeia sufficiently precise. If the process be properly performed, it may, however, be obtained with certainty always the same. The nitrous acid ought to be diluted with rather more than an equal weight of water, so as to act on the quicksilver slowly, and with scarcely any sensible effervescence; the' quicksilver should be added in small quantities at a time, and in as large a quantity ultimately as the acid can dissolve without the application of heat. When the solution appears to have ceased, the liquor is to be poured off from the undissolved quicksilver, and strained ; it is to be diluted cautiously with water, as far as the dilution can be carried without impairing its transparency; and water of ammonia is to be added as long as any precipitation is produced. The precipitate is of a very deep gray colour, approaching to black ; it is to be washed well with water, and dried. In drying, from exposure to the air and light, its colour becomes lighter; still it is a blue gray. In the shops it is usually of a light gray colour, and sometimes almost perfectly white, from the solution of mercury from which it has been precipitated containing the metal in too highly an oxidated state. The College order carbonate of ammonia to be employed in the precipitation; and it might be supposed from this, that the oxide thrown down will receive carbonic acid, and that the precipitate will be a carbonate or sub-carbonate. This, however, is not the case; the carbonic acid is disengaged, and the same precipitate is thrown down by pure ammonia. Some chemists have supposed, that the precipitate is produced with more certainty of a dark colour, when the ammonia is added in the state of carbonate ; but this is a mistake, the darkness of the colour depending entirely on the degree of oxidation of the metal. The London College have given the same name, Oxydum Hydrargyri Cinereum, to a preparation obtained by a different process, but supposed to be essentially the same. An ounce of Sub-muriate of Quick- 240 PREPARATIONS OF QUICKSILVER. silver (Mild Muriate) is boiled in a gallon of Lime Water, stirring it constantly until the gray oxide of quicksilver subsides. This is washed with distilled water and is then dried. This process has been had recourse to from the supposed difficulty of obtaining the gray oxide, by precipitation from nitrate of mercury by ammonia, uniform. It will afford a preparation sufficiently uniform, and so far similar to the other, that the oxide is in a low state of oxidation. But it is not at all probable, that the lime can abstract the whole of the muriatic acid, and it is probably, therefore, what is in strictness of nomenclature, a sub-muriate of mercury. The Gray Oxide of Mercury has been introduced as a substitute for those preparations in which the metal is oxidated by trituration under exposure to the air, and has been supposed to have the advantage of more uniformity of strength, as the others are liable to be variable from imperfect preparation. When properly prepared, it appears to be the same in chemical composition, and the medicinal operation of it is also extremely similar. It is given in the dose of a grain night and morning, usually under the form of pill, and this answers very well as a substitute for the Mercurial Pill. An ointment formed from it, Unguentum Oxidi Hydrargyri Cinerei, has been introduced into the Edinburgh Pharmacopoeia ; one part of the gray oxide being mixed with three parts of lard. This is designed as a substitute for the Mercurial ointment, but it lias been said not to be so easily forced through the cuticle by friction. It has also been used in the state of vapour from the application of heat, for fumigating venereal ulcers. Oxidum hydrargyri rubrum per acidum nitricum, olim Mercurius Praecipitatus Ruber. Red Oxide of Quicksilver by Nitric Acid. (Hydrargyri Nitrico-Oxydum, Ph. Lond. —Ox3 r dum Hydrargyri Nitricum, Ph. Dub.) M Take of Purified Quicksilver, one pound ; Diluted Nitrous Acid, sixteen ounces. Dissolve the quicksilver. PREPARATIONS OF QUICKSILVER. 241 and evaporate the solution with a gentle fire to a white dry mass, which being reduced to powder, is to be put into a glass cucurbit, a thick glass plate being put over its surface. Then a capital being adapted, and the vessel placed in sand, apply to it a fire gradually raised, until it pass into very red small scales." The process in the Dublin and London Pharmacopoeias is the same, equal weights of diluted nitric acid and quicksilver being ordered in the former, and in the latter a shallow vessel being ordered instead of a cucurbit, and the heat being aplied until the powder cease to exhale red vapours. The quicksilver is in this preparation first oxidated by the nitrous acid, and the oxide then combines with the remaining acid. By the increase of heat, this nitrate is decomposed, and the greater part of the acid expelled, leaving a mass of a deep red colour. From the name of oxide given to this preparation by all the Colleges, it appears to be supposed, that the whole acid of the nitrate is expelled or decomposed, and that the residual matter is quicksilver combined with oxygen alone. This has never been established, however, by any accurate analysis of the preparation, and there are very obvious objections to it. Though a red oxide of mercury can be formed by the action of atmospheric air on the metal at a high temperature, it is quite different in its appearance from the product of the present process: and the latter is possessed of a considerable degree of escharotic power not belonging to the former, communicated probably by a portion of nitric acid combined with it. In all cases where a volatile ingredient is expelled from one more fixed by the application of heat, it is now known that the decomposition is scarcely ever complete, the influence of quantity operating, and causing a portion of the volatile ingredient to be retained, the quantity being greater as there is less difference in the volatility of the two substances. It follows, from this alone, as the most probable conclusion, that af hough the greater part of the nitric acid may be expelled from the oxide of Vox,, ii. m PREPARATIONS OF QUICKSILVER. 242 mercury, a portion of it will be retained, and it is probably impossible to expel the whole of it, without raising the heat to that point at which the oxygen itself will be expelled, and the quicksilver be reduced to the metallic form. I have accordingly found, that it does contain nitric acid. If the preparation be boiled for a short time with five or six times its weight of water, the liquor when filtered, has the styptic metallic taste, and gives a white precipitate with water of ammonia, or with carbonate of potash,—a plain proof that it holds dissolved nitrate of mercury ; and to avoid any fallacy, the preparation submitted to experiment was that found in the shops, the product of the process on the large scale, of a bright red colour, and more perfectly prepared than that formed on the small scale. This must therefore be regarded as a sub-nitrate, and the proper appellation to be given to it is, Sub-nitras Hydrargyri Ruber, by which also it will be better distinguished from the proper red oxide. According to Paysse, 100 parts decomposed by heat afford 82 of mercury, and 18 of oxygen; this oxygen probably having an intermixture of nitrogen from the decomposition of the acid. It has always been found very difficult to conduct this process, so as to obtain the product of that bright red colour and scaly appearance which are regarded as tests of its proper preparation. Much of the success depends apparently on the scale on which it is formed, the heat acting more steadily, and with more uniformity, on a large, than on a small quantity. When properly prepared, it is in scales of a bright red colour. It is so acrid as to be altogether unfit for internal administration. Externally it is employed as an escharotic, being applied either in a finely levigated powder, or mixed with lard in the form of ointment. This ointment, composed of one part with eight of lard, is officinal in the Edinburgh Pharr rnacopceia. PREPARATIONS OF QUICKSILVER. 243 Sub-sulphas hydrargyri flavus, olim Turpethum Minerale. Yellow Sub-sulphate of Quicksilver. (Oxydum Hydrargyri Sulphuricum, Ph. Dub.) " Take of Purified Quicksilver, four ounces; Sulphuric Acid, six ounces. Put them into a glass cucurbit, and boil in a sand-bath to dryness. * The white matter remaining at the bottom of the vessel being reduced to powder, is to be thrown into boiling water. It will thus be converted into a yellow powder, which must be frequently washed with warm water." By boiling sulphuric acid on quicksilver, the acid suffers a partial decomposition, oxygen being communicated from it to the metal, and sulphurous acid gas disengaged. The oxide of quicksilver is combined with the remaining acid, forming super-sulphate of mercury. By the continuance of the heat, this is partially decomposed, much of the acid is expelled, and a sub-sulphate of mercury remains. On this, boiling water is poured ; arid it acts as water does on many of the metallic salts. Having a stronger affinity to their acid than to their base, it decomposes the salt, abstracting the acid, and precipitating the oxide; but the influence of quantity on chemical affinity still so far operates in this decomposition, that the acid combined with the water retains a small portion of the oxide combined with it, and the oxide precipitated retains a portion of the acid. The entire compound, therefore, is resolved into a super-salt, which is dissolved, and a sub-salt which is thrown down. This happens in the present process ; the water poured on the sulphate of mercury abstracts the acid, retaining in combination with it a portion of oxide, and forming therefore a super-sulphate of mercury, which remains dissolved, while a sub-sulphate is precipitated, and forms the yellow powder. The colour of this is more lively when hot water is used in its preparation, probably from the temperature favouring the chemical action of the water. The success of the process, with regard to the quantity of product, depends much on the sulphate of mercury having been deprived of all free aeid previous 244 PREPARATIONS OF QUICKSILVER. to the affusion of the water; for if it contain much acid, the greater part pf the salt is dissolved without being decomposed. The proportion of acid ordered in the Pharmacopoeia is unnecessarily large, and rather defeats the object of the process; an equal weight is sufficient, and the heat ought to be applied to the saline mass until it is perfectly dry. The super sulphate dissolved -in the water may be decomposed by potash, and a sub-sulphate precipitated. Yellow sub-sulphate of mercury must, from the nature of the process by which it is obtained, be liable to variation in the proportions of its constituent principles. According to Fourcroy, it consists of 76 of mercury, 11 of oxygen, and 10 of acid, with 3 of water, while another analysis gives the proportion of acid at 15. As a medicine, it is too harsh in its operation to be administered internally, being liable to produce violent vomiting. It has sometimes, however been given as a powerful emetic, in a dose of five grains. It is an errhine, and has been employed as such, mixed with any mild vegetable powder, in some affections of the eyes. Sulphuretum hydrargyri nigrum, olim JEthiops Mineralis. Black Sulphuret of Quicksilver (Sulphuretum Hydrargyri Nigrum, Ph. Dub.) " Take of Purified Quicksilver, Sublimed Sulphur, of each equal weights. Rub them together in a glass mortar with a glass pestle, until the globules of quicksilver entirely.disappear. It may be made likewise with a double proportion of quicksilver." By this trituration a chemical combination appears to be effected between the quicksilver and sulphur, as the former loses completely its metallic form, and no globules can be perceived in the powder by the microscope. It has even been supposed, that the metal is at the same time, imperfectly oxidated, and combined with sulphuretted hydrogen ; but from the researches of Seguin, this does not appear to be the case. The combination is much facilitated by the application of heat, and it can at PREPARATIONS OF QUICKSILVER. 245 once be effected, by adding the quicksilver to the melted sulphur. This is the least active, perhaps, of the mercurial preparations. As an anthelmintic it is sometimes given in a dose of five or ten grains, and it has been used as an alterative. Some additional preparations of mercury have a place in the London and Dublin Pharmacopoeias, and are used in practice. Hydrargyrus cum creta. Quicksilver with Chalk. Ph. Lond. u Take of Purified Quicksilver, three ounces; Prepared Chalk, five ounces. Rub them together until the globules no longer appear." Quicksilver, when triturated with any substance which aids the division of its globules, and extends their surface, appears to be susceptible of oxidation from the action of the atmospheric air, and the gray oxide formed by this operation is the basis of the common mercurial pill, as well as of some other preparations. More than one preparation of this kind, however, for internal administration, is superfluous; and the mercurial pill, prepared by trituration of the quicksilver with honey, manna, or mucilage, being that which has been long established in practice, is to be preferred. The present preparation has nothing peculiar to recommend it. Hydrargyrum cum magnesia. Quicksilver with Magnesia. Ph. Dub. " Take of Quicksilver, Manna, each one ounce; Magnesia, half an ounce. Triturate the quicksilver with the manna in an earthen mortar, adding as much water as will give to the mixture the consistence of syrup, and continuing the trituration until the mercurial globules are so far subdivided as to be no longer visible. Then add to the mixture a drachm of the magnesia, triturating 246 PREPARATIONS OF QUICKSILVER. it constantly. After they are thoroughly mixed together, add a pound of hot water, and shake the mixture ; allow the liquor to rest, and pour it off from the sediment which subsides. Repeat this washing twice, that the manna may be entirely removed ; and while the sediment is still humid, add to it the remaining magnesia. Lastly, dry the powder on bibulous paper." The object of this process is to obtain the oxidation of the mercury by trituration, and the interposition of the soft viscous matter of the manna with the addition of the water may facilitate this ; the subsequent steps of the operation are designed to remove the manna, and obtain the gray oxide mixed with the magnesia. The same observation, applies, however, to this as to the preceding preparation,—that it is superfluous, and that for any useful purpose the mercurial pill will answer equally well. The only advantage, at least, of either process, is, that it may afford a mild preparation that can be given under the form of bolus, where a pill cannot be easily swallowed. A preparation is likwise inserted in the Dublin Pharmacopoeia, under the name of Hydrargyrum cum creta, obtained in the same manner, only substituting precipitated chalk for magnesia. Hydrargyri oxydum rubrum. Red Oxide of Quicksilver. Ph. Lond. (Oxydum Hydrargyri, Ph. Dub.) " Take of Purified Quicksilver, one pound. Put the quicksilver into a glass vessel, with a narrow mouth, and broad at the bottom. Apply heat to this open vessel, raised to the six-hundredth degree, until the quicksilver pass into* red scales; then rub these into a fine powder." At the temperature at which quicksilver boils it combines with oxygen, and when heated to this temperature, under exposure to the air, red scales gradually form on its surface from this combination. There is a difficulty, however, in conducting the process; for if the quicksilver be freely exposed to the air, a considerable quantity PREPARATIONS OF QUICKSILVER. 247 of it is lost, from its vapour being dissipated, especially if the heat be raised a little too high; while, on the other hand, if the air is not freely admitted, the oxidation cannot proceed. The method directed in the formula of the London and Dublin Colleges is the most effectual, — employing a glass vessel broad at the bottom, (so as to present the quicksilver under an extensive surface,) and with a long neck drawn out to a very small aperture, so that while the atmospheric air is admitted, the mercurial vapour will not so easily escape, the heat being applied by the medium of sand. Still the oxidation goes on very slowly, requiring the application of the heat for several weeks; and from the necessity of keeping up a steady heat without allowing it to become too strong, the conducting of the process requires considerable attention, and the preparation is comparatively high priced. Red oxide of quicksilver is in scales of a dark brick red colour. When exposed to the heat of ignition it is decomposed, gives out oxygen, and the quicksilver returns to its metallic form. From the quantity of oxygen obtained by the reduction, Lavoisier inferred that the oxide contains seven parts of oxygen in 100 parts. It is a dangerous mistake which some have made, supposing the red scaly substance obtained from the decomposition of nitrate of mercury by heat to be essentially the same. The latter is much more acrid, and cannot be given internally with safety; and it is to be regretted, that the name of Oxide has been given to it, as it may sometimes lead to its substitution for the present preparation. The red oxide prepared by heat, Calcined Mercury as it was formerly named, is a very active Mercurial. It has also been regarded as certain and permanent in its operation, and has therefore sometimes been employed in the treatment of secondary symptoms of syphilis, where the milder mercurials had failed. Its dose is one grain. It is liable, however, to produce irritation on the stomach or intestines, and from this, as well as from its high price, is not very frequently used. PREPARATIONS OF QUICKSILVER. 248 Hydrargvrus albus. White Precipitate of Mercury. Ph. Lond. (Sub-murias Hydrargyri Ammoniatum, Ph. Dub.) " Take of Oxymuriate of Quicksilver, Muriate of Ammonia, each half a pound ; Solution of Sub-carbonate of Potash, half a pint; Distilled Water, four pints. First dissolve the muriate of ammonia, then the oxymuriate of mercury in the distilled water, and add to these the solution of sub-carbonate of potash; wash the powdej which is precipitated, until it is free from taste; then dry it." A process altogether different, but affording precisely the same product, is given by the Dublin College. " To the liquor which has been poured off from the precipitated sub-muriate of mercury, add as much water of ammonia as is sufficient to precipitate the metallic salt. Wash the precipitate with cold distilled water, and dry it on bibulous paper." When corrosive muriate of mercury is decomposed by ammonia, a white precipitate is thrown down, consisting of the oxide of the muriate, with portions both of acid and of ammonia combined with it; the proportions, according to Fourcroy's analysis of it, being 81 of oxide, 16 of muriatic acid, and 3 of ammonia. It is this precipitate which is formed in both the above processes. In the first, it may be conceived, that the potash of the sub-carbonate of potash, decomposes the muriate of ammonia, by combining with the muriatic acid, and that the ammonia evolved from this decomposes the muriate of mercury, throwing down the white precipitate the same as when ammonia is added directly to a solution of corrosive muriate; or, what affords a more simple, and perhaps a more just view, the potash attracts the acid, both of the muriate of mercury and muriate of ammonia, and the oxide of mercury is precipitated, retaining a portion of the acid combined with it, and having attracted the quantity of ammonia necessary to the constitution of the ternary compound. The other process, that in the Dublin Pharmacopoeia, is simply the PREPARATIONS OF QUICKSILVER. 249 decomposition of corrosive muriate of mercury by ammonia. In the preparation of the mild muriate of mercury by precipitation, it has already been stated, that if a solution of mercury in nitric acid be used, which has been prepared with the application of heat, and which therefore contains the metal more highly oxidated than the minimum, a portion of corrosive muriate of mercury is formed, when the solution is decomposed by muriate of soda It is such a mercurial solution that is ordered in the Dublin Pharmacopoeia for the preparation of the precipitated sub-muriate, and hence the liquor from which the precipitate subsides holds corrosive; muriate dissolved. When decomposed, therefore, by ammonia, as directed by the present formula, it affords the ternary white precipitate. The name given to this preparation by the Dublin College is preferable to that in the London Pharmacopoeia, which is altogether vague Sub- Murias Hydrargyri et Ammonia? is probably the correct appellation. The necessity of the presence of ammonia to its constitution is very well shown from the fact, that, if the corrosive muriate be decomposed by potash, it is a yellow precipitate that is thrown down ; when it is decomposed by heat, ammonia and nitrogen are evolved. This precipitate, when dried, forms a light white powder, which is tasteless and insoluble in water. It is used only externally, generally under the form of ointment, in some cutaneous affections. Hydrargyri sulphuretum rubrum. Red Sulphuret of Quicksilver. Ph. Lond. (Sulphuretum Hydrargyri Rubrum, Ph. Dub.) " Take of Purified Quicksilver, forty ounces ; Sublimed Sulphur, eight ounces. To the sulphur melted over the fire, add the quicksilver, and as soon as the mass swells, remove the vessel from the fire, and cover it closely, that inflammation may not take place ; then rub it into powder, and sublime." The same directions are given in the Dublin Pharmacopoeia. The inflammation which is taken notice of, as liable Vol. II. 33 250 PREPARATIONS OF QUICKSILVER. to happen when the melted sulphur and quicksilver are mingled together, is probably not a real combustion, but the evolution of heat and light from their mutual action ; this taking place in other cases of the combination of sulphur with metals, and being wholly unconnected, as has been sufficiently established, with any agency of the air. The covering of the vessel will therefore not check it, though the removal of it from the fire may do so, by reducing the temperature, and thus suspending the mutual action of the mercury and sulphur. If this should happen, the combination will probably therefore remain imperfect, and the process may succeed less perfectly, or at least succeed only from the action being renewed in the subsequent sublimation. The exclusion of the air must, however, be proper, as preventing a real combustion taking place, when the mass is so much heated. Different opinions have been maintained with regard to the nature of the ultimate product of this progress. Some chemists supposed, that the mercury exists in the state of oxide, in combination with the sulphur, and Vauquelin considered the bright red colour as arising even from a high degree of oxidation ; this oxygen being supposed to be combined with the metal in the first stage of the process, when the apparent combustion takes place. This oxygenation, however, has never been clearly established. And according to Proust and Seguin, the compound is a pure sulphuret, consisting of 85 or 86 of quicksilver, with 15 or 14 of sulphur. This substance, long known by the name of Cinnabar is of a vivid red colour, which becomes still more bright when it is reduced to powder. Its principal medicinal application is for mercurial fumigation. It is easily volatized by heat, and its vapour, directed on the surface of venereal ulcers, checks the progress of the ulceration; and where this is of importance, as from the situation of an ulcer it sometimes is, the practice is employed, a little of the powder being laid on a hot iron, and the vapour directed on the part. PREPARATIONS OF LEAD. 251 PLUMBUM.—LEAD. Acetis plumbi, olim Saccharum Batumi. Acetite of Lead. (Plumbi Super-Acetas, Ph. Lond. —Acetas Plumbi, Ph. Dub.) " Take of White Oxide of Lead, any quantity. Put it into a cucurbit, and pour upon it ten times its weight df Distilled Acetous Acid. Let the mixture stand on warm sand until the acid becomes sweet; pour it off, and add a fresh quantity successively, until it cease to acquire sweetness. Then evaporate the whole liquor, freed from impurities, in a glass vessel, to the consistence of thin honey, and put it aside in a cool place, that, crystals may form, which are to be dried in the shade. Evaporate the remaining liquor, that there may be a new formation of crystals, and repeat this evaporation until no more are formed." The directions in the Dublin. Pharmacopoeia are similar. In the London Pharmacopoeia, a pound of cerusse is ordered to be boiled in a gallon and a hall of vinegar, until the acid is saturated ; the liquor is then poured off, and evaporated until a pellicle appear on its surface, when it is put aside to crystallize. The process, however, is never attempted in the shops, but is conducted on a large scale, to furnish the salt for the purposes to which it is applied in the arts : distilled vinegar being either boiled on ceruse until the acid is saturated, or plates of lead being moistened with vinegar, or partially immersed in it, until they are incrusted with oxide, this oxide being dissolved by immersing the plates in the liquor, and a new quantity being formed by raising them to the surface. This is continued until the acid is saturated, and in either case the liquor is brought by evaporation to crystallize. It is obvious, that in this process the acetic acid of the distilled vinegar combines with the oxide of lead. The salt which crystallizes was supposed to be the neutral acetate; but from more recent researches it appears to be a super acetate, and this name is accordingly given to it by the London College. The neutral acetate dot**; PREPARATIONS OF LEAD. 252 not crystallize easily ; and it was found by Thenard, whose attention was called to it, from this circumstance, that a slight excess, of acid favours the crystallization, and that this excess of acid enters into the composition of the salt. It consists, according to the analysis of it by this chemist, of 58 oxide of lead, 26 acetic acid, and 16 of water, while the neutral salt is composed of 78 of oxide of lead, 17 acetic acid, and 5 of water. This salt crystallizes in acicular prisms, and as prepared on a large scale, is usually in the form of masses composed of these crystals aggregated ; it is white, or of a light yellowish colour, with a silky lustre, is rather efflorescent ; it has a sweet taste, whence the name of Sugar of Lead, by which it has been known, this sweetness being accompanied with a degree of astringency. It is soluble in water, requiring about 24 parts at 60° for its solution; with spring water, the solution is milky, from a partial decomposition of the salt, by the minute quantity of sulphates or muriates contained in the water ; and even with distilled water the solution is not perfectly transparent, if a targe quantity of the water be employed, the water, when its affinity to the acid is aided by its quantity, producing a slight partial decomposition. Acetate, or rather super-acetate of lead, is employed principally as an external application. Its solution in water is used as a collyrium in ophthalmia, as an astringent injection in gonorrhoea, as a wash in superficial inflammation ; and dissolved in vinegar, it is employed as a discutient. These applications of it have already been pointed out under its medical history. Liquor plumbi acetatis. Solution of Acetate of Lead. Ph. Lond. (Liquor Sub-Acetatis Lithargyri, Ph. Dub.) " Take of the Semi-vitrified Oxide of Lead ("Litharge) two pounds four ounces ; Acetic Acid (Vinegar), one gallon. Mix them and boil down to six pounds, stirring constantly ; then put the liquor aside, that the impurities may subside, and strain it." PREPARATIONS OF LEAD. 253 This preparation was introduced by Goulard, a French surgeon, under the name of Extract of Lead, as possessed of peculiar powers, and from the confidence with which it was recommended was established in practice. It was considered by the chemists as a solution merely of oxide of lead in acetic acid, analogous to the crystallized salt. But from the investigation of it by Dr. Bostock, it is proved to have no excess of acid, but to consist of the neutral acetate dissolved in water, and hence the solution is strongly impregnated with oxide of lead. One hundred parts of the saturated solution contain, according to his analysis, 25.1 of oxide, 5 of acetic acid, and 71.9 of water, while 100 parts of the saturated solution of the super-acetate contain 16.8 of oxide, 7.5 of acid, and 75.7 of water. The solution, or Goulard's Extract, as it is named, is of a brown colour. When kept, it becomes lighter, and deposites a quantity of oxide. It is used as a discutient, being mixed with vinegar and water, and frequently applied under the form of cataplasm. It forms also an application to inflamed surfaces, generally under the form of the following preparation, which has been admitted as officinal by the London College. Liquor plumbi acetatis dilutus. Dilute Solution of Acetate ol Lead. Ph. Lond. " Take of Solution of Acetate of Lead, a drachm ; Distilled Water, a pint; Proof-Spirit, a fluid drachm. Mix them." This is what Goulard named absurdly Vegeto-Mineral Water, and which has been highly celebrated as an application in superficial inflammation. It is occasionally employed by surgeons, and some have thought it superior to a simple solution of acetate or super-acetate of lead. 254 PREPARATIONS OF ZINC. ZINC UM.—ZINC. Carbonas zinci impurus pr*:paratus, olim Lapis Calaminaris Prwparatus. Prepared Impure Carbonate of Zinc, formerly Prepared Calamine Stone. (Calamina Pra?parata, Ph. Lond.—Lapis Calaminaris Praeparatus, Ph. Dub.) " Procure the Impure Carbonate of Zinc roasted, from those who prepare brass, and let it be prepared in the same manner as Carbonate of Lime." Calamine is an ore ot Zinc, the composition of which is variable. Some varieties of it appear to consist of oxide of zinc, combined with siliceous earth ; but the more common varieties are composed of the carbonate more or less pure. When calcined by a moderate heat, it becomes friable so as to be more easily reduced to powder; and as this calcination is performed in preparing it for converting copper into brass by cementation, it is ordered in the Pharmacopoeia to be obtained in this state, and then to be reduced to a fine powder by levigation, and washing in the same manner as carbonate of lime Considerable care requires to be taken in this levigation, as the powder is applied to purposes, where, if it were coarse, it would prove irritating. It is used as an application to superficial inflammation and excoriation, dusted oh the part, and it forms the basis of the common healing cerate, to which it communicates a degree of consistence and tenacity. Oxidum ztnci impurum pRyEPARATUM, olim Tutia Praiparala. Prepared Impure Oxide of Zinc, formerly Prepared Tutty Ph. Ed. " Let Tutia be prepared in the same manner as Carbonate of Lime." Tutia is a substance, the origin of which is somewhat doubtful; it consists of oxide of zinc with argillaceous earth; and the most probable account with regard to it is, that it is the sublimate collected in the chimneys in which zinc is calcined, mixed with clay and water, and PREPARATIONS OF ZINC. 255 baked. It is used externally lor the same purposes as calamine, and hence requires to be well levigated. Oxidum Zinci. Oxide of Zinc. (Zinci Oxydum, Ph. Lond.—Oxydum Zinci, Ph. huh.) " Let a large crucible be placed in a furnace filled with burning fuel, in such a manner that it shall be somewhat inclined to its mouth ; and, when the bottom of the crucible is at a moderate red heat, throw in a piece of zinc, about the weight of one drachm. The zinc soon inflames, and is converted into white flocouli, which are to be removed, from time to time, from the surface of the metal, with an iron spatula, that the combustion may proceed more perfectly; and when the inflammation ceases, remove the oxide of zinc from the crucible. Another piece of zinc being thrown in, the operation is to be renewed and repeated as often as may be necessary. Lastly, let the oxide of zinc be prepared in the same manner as carbonate of lime." In the London and Dublin Pharmacopoeias, the crucible is directed to be covered with another one inverted over it, but so as to admit the air,—a direction not easily observed, as the zinc requires to be stirred to renew its suriace, and keep up the combustion. Zinc is the most inflammable of the metals. At the temperature of ignition, it attracts the oxygen of the atmospheric air, and burns vividly with a white and green light, producing an oxide in very light flocculi, which arc in part carried off by the rapid current of air arising from the burning zinc. This oxide accumulates so rapidly, that it must be withdrawn to allow the combustion to proceed. Particles of metallic zinc are intermingled with it, and hence the necessity of submitting it to levigation. It is light, white, tasteless, and insoluble in water, and contains about 20 of oxygen in 100 parts. In medicine it is employed as an antispasmodic in epilepsy and chorea. It dose is from two to five grains twice a-day, and this gradually increased. It also forms the basis of a healing cerate. PREPARATIONS OF ZINC. 256 Sulphas zinci, olim Vitriolum Album. Sulphate of Zinc. (Zinci Sulphas, Ph. Lond. —Sulphas, Zinci, Ph. Dub.) " Take of Zinc, cut into small pieces, three ounces: Sulphuric Acid, five ounces; Water, twenty ounces. Mix them, and the effervescence being finished, digest f<5r some time on warm sand. Then strain the liquor through paper; and, after due exhalation, put it aside that crystals may be formed." The sulphuric acid in this process, by a resulting affinity, enables the zinc to decompose the water, attracting its oxygen, the hydrogen being disengaged with effervescence : the oxide combines with the acid, forming the sulphate, and by the evaporation this is obtained in acicular crystals. The process, however, is scarcely ever performed in the shops, the sulphate of zinc being prepared on a large scale, from certain varieties of the native sulphuret of the metal. These are roasted, and exposed to air and humidity; oxygen is absorbed, the zinc is oxidated, and the sulphur converted into sulphuric acid ; and the sulphate of zinc is extracted by lixiviation. Its solution is evaporated so far, that on cooling, the sulphate of zinc concretes in a granular mass, forming the white vitriol of commerce. It usually contains a little sulphate of iron, and sometimes, it has been supposed, a portion of sulphate of copper and of lead. From the insolubility of the latter salt, it can scarcely be present; the sulphate of copper is scarcely ever to be discovered, and the sulphate of iron is in small quantity, and cannot communicate any injurious quality. And as sulphate of zinc is principally employed externally, the neglect of this process, and the substitution of the common white vitriol, is of less importance. Sulphate of zinc is used principally as an astringent, in the form of solution; as an injection in gonorrhoea, and a colyrium in ophthalmia : sometimes also internally as an emetic. These applications of it have been already considered. PREPARATIONS OF ZINC. 257 Solutio sulphatis zinci. Solution of Sulphate of Zinc. " Take of Sulphate of Zinc, sixteen grains; Water, • ;ight ounces; Diluted Sulphuric Acid, Sixteen drops. Dissolve the sulphate of zinc in water; then the acid being added, strain through paper." This solution is designed lo be used as a collyrium in ophthalmia, the sulphuric acid dissolving any excess of oxide that may be present in the common sulphate of zinc, if it be employed, and coinciding with it in astringency As an injection in gonorrhoea, the solution, without the acid, is preferable, as sufficiently astringent and less irritating. Solutio acetitis zinci. Solution of Acetite of Zinc. " Take of Sulphate of Zinc, one drachm; Distilled Water, ten ounces. Dissolve it. Take also of Acetite of Lead, four scruples; Distilled Water, ten ounces. Dissolve it. Mix the solutions. Let the liquor remain at rest a little; then strain it." Sulphate of zinc and acetate of lead being the two astringent salts which usually form the basis of the astringent injection employed in gonorrhoea, they had frequently been conjoined in one formula, without the prescriber perhaps being always aware of the decomposition they suffer. The solution, however, was found to answer sufficiently well, being astringent without proving irritating. The use of it led to the introduction of the present process, in which the proportions are properly adjusted. The two salts exchange their principles, the sulphuric acid of the sulphate of zinc combining with the oxide of lead of the acetate of lead, while the acetic acid unites with the oxide of zinc : the sulphate of lead being insoluble, is precipitated, and is removed by filtration; the acetate of zinc remains dissolved. Vol. II. 34 PREPARATIONS OF TIN. 258 Tinctura acetatis zinci. Tincture of Acetate of Zinc. Ph. Dub. " Take of Sulphate of Zinc, one ounce; Acetate of Potash, the same quantity. Triturate them together, and add of Rectified Spirit, one pint. Macerate for a week, agitating the liquor frequently, and strain it through paper." In this process a similar decomposition takes place, the sulphuric acid of the sulphate of zinc combining w ith the potash of the acetate of potash, while the acetic acid enters into union with the oxide of zinc. The spirit d olves the acetate of zinc, while the sulphate of potash remains in a great measure undissolved. The solution is strongly impregnated with the metallic salt, and a collyrium or injection of the usual strength may be prepared extemporaneously, by adding a certain proportion of it to water. The formula appears, however, to have no advantage over the more direct and simple method given by the Edinburgh College. ST ANN U M.—TIN. Pulvis stanni. Powder of Tin. Ph. Dub. " Take of Tin, any quantity. Having melted it in an iron mortar, agitate it as it cools, until it is reduced to powder, which, when cold, is to be passed through a sieve." Tin, when heated near to its melting point, becomes extremely brittle, so as to be easily reduced to fragments. When melted, therefore, if stirred or agit' ted as it becomes solid, this effect is obtained, and a granular powder is formed more easily than by any other method. Its powers as an anthelmintic have been already considered. PREPARATIONS OF ARSENIC. 259 ARSENICUM.—ARSENIC. Arsenici oxydum prjeparatum. Prepared Oxide of Arsenic. Ph. Lond. "Triturate Oxide of Arsenic into powder; then put it into a crucible, and applying hear, sublime it into another crucible placed over the former." Oxide of arsenic is usually obtained by sublimation from the ores of cobalt in which it is contained, and which are roasted with the view of obtaining the oxide of cobalt for the purposes to which it is applied in the arts. The arsenical oxide is collected in the chimney and flues of the furnace; it is impure, but is usually purified by sublimation before it is brought to the shops, and is in the state either of a solid cake or a powder. Oxide of arsenic is a substance so very active, that any foreign matter it can contain in this state can be of no importance, and the present process is altogether superfluous. Its properties and medicinal applications have been already considered. Liquor arsenicalis. Arsenical Solution. Ph. Lond. " Take of Prepared Oxide of Arsenic, rubbed to a very fine powder, Sub-carbonate of Potash from Tartar, of each sixty-four grains: Distilled Water, a pint. Boil them together in a glass vessel until the arsenic is entirely dissolved To the solution when cold, add Compound Spirit of Lavender, four fluid drachms. Then add as much Distilled Water as may be necessary to make up the measure of a pint " The substance named Oxide of Arsenic has by some chemists been considered as an acid, and named Arsenious Acid. It is not, like the greate r number of oxides, insipid and insoluble in water, but lias a sharp taste and is soluble in not more than 80 parts of cold, and 15 of boding water. It reddens the more delicate vegetable colours, particularly the infusion of litmus, and it combines with the alkalis. The alkaline properties, however, 260 PREPARATIONS OF ARSENIC. do not appear to be neutralized in these combinations ; and it even neutralizes, as Berthollet affirms, the acids in combining with them. And hence, on the whole, it is to be regarded as an oxide in a high degree of oxidation. By combination with potash it is rendered soluble in water, and to render the solution of it perfect, and obtain it in a form in which its dose can be easily regulated, is the object of the present process. The formula was introduced by Fowler, as giving a substitute for the arsenical preparation, known under the name of Tasteless Ague Drop. Each ounce of the solution contains four grains of the oxide. The dose is four drops three times a day, as a remedy in intermittent fever, given with the precautions which have been pointed out under its medical history. The spirit of lavender is designed merelv to communicate colour and flavour: but it would j » have been better to have added some other tincture, the flavour of which is less commonly known, and the taste less grateful, so as to have guarded against the possibility of the solution being incautiously swallowed. Arsenias kali. Arseniate of Potash. Ph. Dub. 44 Take of White Oxide of Arsenic, Nitrate of Potash, each one ounce." Reduce them separately to powder; mix them, and put the mixture into a glass retort, placed in a sand-bath, and apply heat, raising it gradually until the bottom of the retort is obscurely red. The vapours which arise should, by an apparatus adapted to that purpose, be transmitted through distilled water, that the nitrous acid disengaged by the heat may be condensed. Dissolve the residual matter in four pounds of boiling distilled water, and after due evaporation put it aside, that crystals may form. Arsenic, by a high degree of oxygenation, acquires unequivocally the properties of an acid. This acid, the Arsenic, as it is named, is formed by distilling nitrous acid from the oxide of arsenic, the nitrous acid yielding POWDERS. 261 to the oxide the requisite proportion of oxygen. The same change is produced by the present process; the nitrous acid being decomposed, the oxide of arsenic acquiring from it as much oxygen as converts it into arsenic acid, and this acid remaining combined with the potash of the nitre. The residual mass, therefore, when a sufficient degree of heat has been applied to expel or decompose the whole of the nitrous acid, is arseniate of potash. This salt is very soluble in water, and crystallizable. By evaporation of its solution it is obtained in large regular crystals, their figure being a tetraedral prism : in this form, and as obtained by this process, the salt has generally a slight excess of acid; when perfectly neutral, it does not crystallize so easily. Under this form, as well as under that of the preceding preparation, arsenic has been employed as a remedy in intermittent fever, and in some cutaneous diseases. The dose is from one-sixteenth to one-eighth of a grain of the crystallized salt. It does not appear to have any advantage, however, over the more simple preparation. CHAPTER XXI. PULVERES.—POWDERS. This is the simplest form of composition of medicines, the different articles being merely reduced to powder, and mixed together. It is adapted to the exhibition of such remedies as are not ungrateful, and such as are not liable to lose their virtues by keeping; and is usually an improper form for those which are bitter, acrid, or foetid, which require to be given in a large dose, or which are not easily diffused in water, the vehicle in which powders are usually taken. The dose of a powder seldom exceeds a drachm ; and if it. require to be given only in a few grains, it is better that POWDERS. 262 it should be under the form of bolus. When it is to be taken, it is merely diffused in water, wine, or any other convenient vehicle. Pulvis aromaticus. Aromatic Powder. (Pulvis Cinnamomi Compositus, Ph. Lond. —Pulvis Aromaticus, Ph. Dub.) " Take of Bark of Cinnamon, Cardamom Seeds, Ginger Root, Jf each equal parts. Rub tiiem into a very fine powder, which is to be kept in a glass phial weil stopt." In the London and Dublin Pharmacopoeias the proportion of cinnamon is larger, and a small quantity of long pepper is likewise added. This combination of aromatics is designed merely to communicate to other compositions fragrance and pungency, and to obviate the nausea which ungrateful medicines are liable to excite. The quantity added to a dose is generally about five grains. Pulvis asari compositus Compound Powder of Asarabacca. (Pulvis Asari Compositus, Ph. Dub.) " Take of the Leaves of Asarabacca, three parts ; the Leaves of Marjoram, Flowers of Lavender, of each one part. Rub them together to a powder." In the composition which has a place in the Dublin Pharmacopoeia, the leaves of marjoram are omitted. This is used as a mild errhine, forming the composition known by the name of Herb Snuff. When snuffed in the quantity of a few grains, it occasions sneezing and a discharge of mucus, and is sometimes used in headach and ophthalmia. Pulvis carbonatis calcis compositus, olim Pulvis Cretaceus. " Take of Prepared Carbonate of Lime, four ounces; Bark of Cinnamon, one drachm and a half; Nutmeg, half a drachm. Rub them together to powder." This is designed to be used as a grateful antacid. It is given in the dose of one drachm. POWDERS. 263 Pulvis cretje compositus. Compound Powder of Chalk. Ph. Lond. " Take of Prepared Chalk, half a pound ; Bark of Cinnamon, four ounces ; Tormentil Hoot, Gum-Arabic of each three ounces; Long Pepper, half an ounce, deduce them separately to powder, and mix them." This composition, though analogous to the preceding one, is so far different as to require to be noticed apart, the proportion of the aromatics being larger, and the addition of the tormentil root rendering it more astringent. It is used to relieve diarrhoea arising from acidity being given in the dose of half a drachm or a drachm. Pulvis cretje compositus cum opio. Compound Powder of Chalk with Opium. Ph. Lond. " Take of Compound Powder of Chalk, six ounces and a half; Hard Opium, rubbed to powder, four scruples. Mix them " The addition of opium to astringents and antacids, when given in diarrhoea, is a common practice, and this formula affords a convenient composition of this kind. Its dose is one scruple, or half a drachm Two scruples contain one grain of opium, the proportion having been diminished a little from what it was in former editions of the Pharmacopoeia. Pulvis jalaps compositus. Compound Powder of Jalap. " Take of the Powder of the Root of Jalap, one part; Super Tartrate of Potash, two parts. Rub them together into a very fine powder." This combination affords an excellent purgative, less stimulating, and less liable to excite griping than the jalap alone. It is given in the dose of a drachm or a drachm and a half; and in dropsy, as a hydragogue cathartic, to the extent of two drachms. POWDERS. 264 Pulvis ipecacuanha et opii, olim Pulvis Doveri. Powder ol' Ipe cacuanhaand Opium. (Pulv. Ipecacuanhas Compositus, Ph. Loud, Dub.) " Take of the Powder of the Root of Ipecacuanha, Opium, of each one part; Sulphate of Potash, eight parts. Rub them together into a fine powder." This composition, Dover's Powder, has long been established in practice, and is one of those useful combinations, which experience, or rather accident discovers, the powers of which could not have been inferred d priori from the known operation of its ingredients. It affords one of the best examples of the power which one medicine has of modifying the action of another, the ipecacuan rendering the operation of the opium, as a sudorific, much more certain than it otherwise would be, and appearing also to diminish its narcotic effect, so that the composition can be given with safety in pure inflammatory affections, in which opium alone would be hazardous. The sulphate of potash serves to divide the particles of the opium and ipecacuan, and mix them more intimately; and such is the advantage derived from it, that, as Dr. Blane has remarked, the opium and ipecacuan alone, mixed in the above proportions, have not the same effect. Hence, too, the operation of the powder is always more certain when it has been triturated to a great degree of fineness. This powder is the most powerful and certain sudorific we possess. Its medium dose is fifteen grains, the operation of which is to be assisted by the sweating regimen ; and frequently it is necessary to give additional smaller doses at intervals, to produce sweat. Its principal use is in acute rheumatism ; but it is prescribed in all cases with propriety where full sweat ing is to be induced. Pulvis opiatus. Opiate Powder. " Take of Opium, one part; Prepared Carbonate of Lime, nine parts. Rub them together to a fine powder." This is designed as a convenient form for administer- POWDERS. 265 ing opium. Ten grains contain a grain of opium, and form a medium dose. It is however little used. Pulvis cornu usti cum opio. Powder of Burnt Hartshorn with Opium. Pharm Lond. " Take of Hard Opium rubbed to powder, one drachm , Burnt and Prepared Hartshorn, an ounce; Cochineal in powder, a drachm. Mix them." This, in the former edition of the Pharmacopoeia, had the name of Pulvis Opiatus, which has been changed to its present appellation, as less liable to being conlounded with Powder of Opium. A little cochineal is also added to give it colour. The burnt hartshorn serves to divide the opium, and from its hardness and grittiness is better adapted to this than the chalk of the preceding preparation. One grain of opium is contained in ten of the powder. Pulvis scammonii compositus. Compound Powder of Scammony. " Take of Scammony, Super-Tartrate of Potash, of each equal parts. Rub them together into a very fine powder." Scammony given alone, is liable to act as a purg tive rather with violence, w hile its operation is at the same time somewhat uncertain. By the addition of the supertartrate of potash, its cathartic operation is rendered more certain and less irritating. It is also preferred to the scammony alone, as a hydragogue cathartic. Its dose is from ten to twenty grains. Pulvis scammonii compositus Compound Powder of Scammony. Pharm. Lond. " Take of Scammony, Hard Extract of Jalap, of each two ounces ; Ginger, half an ounce. Rub them separately into a very fine powder, then mix them." This composition, though under the same name as the preceding one, is of a very different nature; the stivol. ii. is POWDERS. 268 preparation. One part of opium is contained in twenty,, and it may be given in a dose from ten to twenty grains. Pulvis senna compositus. Compound powder of Senna. Pharm. Lond. " Take leaves of Senna, Super-Tartrate of Potash, of each two ounces; Scammony, half an ounce ; Ginger, two drachms. Rub the scammony separately, the others together, into a fine powder, and mix them." This may be employed as a purgative, in a dose of from half a drachm to a drachm. The senna is, however, a substance so inferior in power to the scammany, that there appears to be little advantage in their combination, nor is the form of powder well adapted to their exhibition. Pulvis tragacantha compositus. Compound Powder of Tragacanth. Pharm. Lond. " Take of Tragacanth, rubbed to powder, Gum Arabic in powder, Starch, of each one ounce and a half; Refined Sugar, three ounces. Triturate the starch and sugar together into ponder, then having added the tragacanth and the gum Arabic, mix them all together." This combination of mucilaginous substances may be employed for the general purposes of demulcents, in the dose of a drachm, or two drachms, frequently repeated. But it appears to be a very superfluous composition. CHAPTER XXII. ELECTU ARIA.—ELECTUARIES. This term is applied to that form of compound medicines where the consistence is nearly that of thick honey. An electuary is composed, in general, of a powder reduced to the proper consistence by the addition ELECTUARIES. 269 of syrup or mucilage. It is a proper form for administering medicines which are not very disagreeable in their taste or flavour; and, except in a few officinal preparations, it is an extemporaneous prescription, as when long kept it is liable to become too thick and adhesive from the evaporation of part of its moisture. Dry powders generally require twice their weight of syrup to bring them to the due consistence ; and syrup is preferable to mucilage, as the electuary made with the former does not so soon become dry. The common dose of an electuary rarely exceeds two tea-spoonfuls, and is seldom less than a tea-spoonful; any very active medicine, which requires to be given in a smaller dose, being usually administered under the form of bolus. The London College have united the electuaries with the Conserves, as they are both compositions of vegetable matter with sugar, and are of similar consistence ; and have given to them the common name of Confections. In conserves, however, the addition of the saccharine matter is in much larger proportion, and is designed to preserve the vegetabfe matter; in electuaries, the syrup is designed merely to communicate the required form. The Edinburgh College retain the distinction of conserves, and the individual preparations which have this name have been already considered. Electuarium aromaticum. Aromatic Electuary. (Confectio Aromatica, Ph. Lond. —Electuarium Aromaticum, Ph. Dub.) " Take of Aromatic Powder, one part; Syrup of Orange-Peel, two parts. Mix, beating them well together, so as to form an electuary/' The composition which has a place in the other Pharmacopoeias is somewhat different. The following is the formula given by T the London College : " Take of Cinnamon Bark, Nutmegs, each two ounces; Cloves, one ounce ; Cardamom Seeds, half an ounce; Saffron dried, two ounces ; Prepared Shells, sixteen ounces; Refined Sugar, two pounds; Water, a pint. Triturate the dry substances together 270 ELECTUARIES. into a fine powder, then add the water gradually, and mix them so as to form an uniform mass." The composition of the Edinburgh Pharmacopoeia is the more simple of these ; and in that of the London Pharmacopoeia, the carbonate of lime is foreign to the object of the combination, though, as it has long had a place, it is still retained. Either electuary is a grateful aromatic preparation, frequently combined with other medicines, or made the basis of cordial or carminative mixtures, requiring merely for this purpose to be diffused in water with a little syrup. Electuarium cassia fistula. Electuary of Purging Cassia. (Confectio Cassia?, Ph. Lond. —Electuarium Cassiae, Ph. Dub.) " Take of the Pulp of Cassia in pods, four parts; Pulp of Tamarinds, Manna, of each one part; Syrup of Pale Rose, four parts. Dissolve the manna beat in a mortar, with a gentle heat, in the syrup; then add the pulps, and, by a continued heat, reduce the mixture to a proper consistence." The composition with regard to the ingredients is the same in the other Pharmacopoeias. This electuary affords a mild laxative, which operates in the dose of an ounce. From the predominance of the pulps and the saccharine matter, it is liable, however, to become sour on keeping; it is also inferior in activity to the next electuary, which is equally pleasant, and hence, it is so little used, that it is never found in the shops. Electuarium cassia senna, olim Electuarium Lenitivum. Electua- ry of Senna. (Confectio Senna?, Ph. Lond. —Electuarium Sennae, Ph. Dub.) " Take of the Leaves of Senna, eight ounces ; Coriander Seeds, four ounces; Liquorice Root, three ounces; Figs, Pulp of Prunes, of each one pound; Pulp of Tamarinds, half a pound; Refined Sugar, two pounds and a half. Bruise the senna with the coriander seeds, and separate by passing through a sieve ten ounces of the mixed powder. Boil the residuum with the figs and ELECTUARIES. 271 the liquorice in four pounds of water to one half; then express and strain. Reduce the strained liquor by evaporation, to about a pound and a half. Afterwards add the sugar so as to make a syrup. Add this syrup gradually to the pulps, and, lastly, mix in the powder." The composition in the London Pharmacopoeia is the same, with the addition of half a pound of Pulp of Cassia. In the Dublin Pharmacopoeia it is different; the ingredients being, Senna Leaves in fine powder, four ounces; Pulp of Prunes, a pound; Pulp of Tamarinds, two ounces ; Syrup of Brown Sugar (Molasses), a pint and a half; Essential Oil of Carraway, two drachms. This electuary is in very common use as a mild and pleasant purgative. Its dose is six drachms, or an ounce; and it is sometimes rendered more active by the addition of a little jalap, or super-tartrate of potash. The electuary of the Dublin Pharmacopoeia, though more simple than the others, must be less grateful, from containing so large a proportion of molasses ; and the oil of carraway will communicate rather too much pungency to a medicine in this form. Electuarium mimosa catechu, olim Confectio Japonica. Electuary of Catechu. (Electuarium Catechu Compositum, Ph. Dub.) " Take of Extract of Catechu, four ounces; Kino, three ounces ; Bark of Cinnamon, Nutmeg, of each one ounce; Opium, diffused in a sufficient quantity of Spanish White Wine, one drachm and a half; Syrup of Red Rose, boiled to the consistence of honey, two pounds and a quarter. Reduce the solid ingredients to powder, and, mixing with them the opium and syrup, form an electuary." In the Dublin Pharmacopoeia, the nutmeg is omitted, the quantity of cinnamon being proportionally increased, and the Syrup of Ginger is substituted for Syrup of Rose : the proportion of opium is the same. In this electuary, the more powerful vegetable astringents are combined ; they are rendered more grateful by ELECTUARIES. 272 the addition of the aromatics, and the efficacy of the composition, as a remedy in diarrhoea, is increased by the opium. It is the basis of the common extemporaneous astringent mixture; two drachms of it being diffused with a little syrup in six ounces of water, and a table spoonful of this being taken three or four times a day. One grain of opium is contained in rather more than three drachms. Electuarium opiatum, olim Ectucerium Thebaicum. Opiate Electuary. (Confectio Opii, Ph. Lond.) " Take of Aromatic Powder, six ounces; Virginian Snake-root, rubbed to a fine powder, three ounces; Opium diffused in a sufficient quantity of Spanish White Wine, half an ounce ; Syrup of Ginger, one pound. Mix, so as to form an electuary." The formula in the London Pharmacopoeia is somewhat different from this. It prescribes of " Hard Opium, rubbed to powder, six drachms ; Long Pepper, an ounce; Gingerroot, two ounces ; Carraway Seeds, three ounces ; Syrup, a pint. Triturate the opium with the syrup heated, then add the other ingredients ground to powder, and mix them." This is a substitute for compositions once highly celebrated, and which have long kept their place in the Pharmacopoeias of Europe, the Mithridate and Theriaca, and which at one period consisted of above an hundred ingredients. Opium appeared, amid this farrago, to be the ingredient of predominating power, modified principally by aromatics; they have been, therefore, gradually reformed into the present preparation, and even it is scarcely used. Each drachm, prepared according to the formula in the Edinburgh Pharmacopoeia, contains a grain and a half of opium ; and rather more in that prepared by the prescription of the London College, thirty-six grains of the latter containing one grain. ELECTUARIES. 273 It remains to take notice of those Electuaries or Confections as they are named, which are peculiar to the London Pharmacopoeia. Confectio amygdala. Almond Confection. " Take of Sweet Almonds,an ounce ; Gum Arabic in, powder, a drachm ; Refined Sugar, half an ounce. The almonds having been previously macerated in water, and their external pellicle removed, beat the whole together, until they form an uniform mass." This is introduced as affording an easy and convenient mode of preparing the almond emulsion extemporaneously ; a little of this confection forming it by diffusion in water. Confectio ruta. Confection of Rue. " Take of the Dried Leaves of Rue, Carraway Seeds, Bay Berries, ol each an ounce and a half; Sagapenum, half an ounce ; Black Pepper, two drachms; Clarified Honey, sixteen ounces. Triturate the dry ingredients into a fine powde ; then having added the honey, mix them all together." This is intended merely as the basis of a moderately stimulating enema, sometimes given in the hysteric paroxysm, and in flatulent colic. Confectio scammonia. Confection of Scammony, Ph. Lond. (Electuarium Scammonii, Ph. Dub.) " Take of Scammony Powder, an ounce and a half; Cloves, bruised, Ginger-Root in powder, of each six; drachms; Oil of Carraway, half a fluid drachm ; Syrup of Rose, as much as may be necessary. Triturate the dry substances into a very fine powder; then having added the syrup, rub them again ; and, adding the oil of carraway, mix them loge'her." The composition in the Dublin Pharmacopoeia is nearly the same, the ciove> Vol. II. 36 274 PILLS being omitted, and their oil added instead of oil of carraway. This is a stimulating cathartic, not very frequently employed. It is given in a dose of from half a drachm to a drachm. CHAPTER XXIII. PILULiE.—PILLS. Pills are formed from a mass sufficiently stiff and adhesive to preserve the round form which is given to them. Under tliis form, such medicines are generally exhibited are as nauseous, either in taste or flavour, and such as operate in a small dose. Few general rules require to be given with regard to their formation. Such of the ingredients as are capable of being reduced to powder, are first triturated to the requisite fineness; those which are of a softer consistence are then added, and if this is not sufficient to bring the whole to a proper consistence, a small quantity of syrup or mucilage is to be added ; the former is preferable, as the latter in drying, is liable to render the mass too hard. Some substances, as several of the gum-resins, become soft on beating, so as to form into pills. Light vegetable powders, when beat up with syrup, form a mass which is not sufficiently coherent to roll out. In this case it is necessary to add a small quantity of pure soap, which gives the necessary tenacity. Metallic preparations, which are heavy, and given in a small dose, are made into pills by the addition of some extract or conserve. If the pill mass is too soft, so that the pills, after being formed, do not keep their form, it may be made harder by the addition of a small quantity of any inactive vegetable matter, as powder of liquorice. After they are rolled out, they must, to prevent them from adhering, PILLS 275 be covered with the same powder, or, what is preferable, as less liable to become mouldy, starch or carbonate of magnesia. A pill ought not to exceed five grains in weight, or twelve may be formed from a drachm of the mass. I hey ought not to be prepared in too large a quantity at a time, as if long kept they become so hard as to be scarcely acted on in the stomach. Pilule Aloetick. Alot'tic Pills. " Take of Socotorine Aloes reduced to powder, Soap, of each equal weights. Beat them with Simple Syrup, so as to make a mass fit for pills." Pilula aloes composite. Compound Aloes Pills. Pharm. Lond. Take of Socotorine Aloes, in powder, one ounce; Extract of Gentian, half an ounce; Oil of Carraway, forty minims ; Syrup, as much as necessary. Beat them together until they form a mass." In this formula the proportion of extract of gentian is too large, the mass being too soft to form properly into pills. It affords a convenient form for the exhibition of aloes, and is in common use as a purgative. Its medium dose is 10 or 15 grains. Under either of these simple forms aloes is very commonly exhibited as a cathartic. Two pills are a medium dose. Pilulje aloes cum zingibere. Pills of Aloes with Ginger Ph. Dub. " Take of Heptatic Aloes, one ounce ; Ginger Root in powder, one drachm ; Spanish Soap, half an ounce ; Essential Oil of Peppermint, half a drachm. Triturate the aloes with the ginger to powder, add the soap and essential oil, and form the whole into one mass." This composition is adapted to the same purposes as the preceding pill, the essential oil communicating some aromatic flavour and pungency. Their dose is the same. 276 PILLS. Pilula aloes et assafoetida. Pills of Aloes and Assafcetida. " Take of Socotorine Aloes in powder, Assafcetida, Soap, of each equal parts. Beat them into a mass with mucilage of Gum Arabic." These pills are occasionally employed in hysteria, in dyspepsia attended with flatulence, and in tympanitis, two or three being taken at bedtime. They will at least prove useful by obviating costiveness. PlLULiB ALOES CUM COLOCYNTH1DE. Pills of Aloes with Colocynth. " Take of Socotorine Aloes, Scammony, of each eight parts; Colocynth, four parts; Sulphate of Potash with Sulphur, Oil of Cloves, of each one part. Let the aloes and scammony be reduced, with the salt to powder, then let the colocynth, rubbed into a fine powder, and the oil, be added. Lastly, beat them with mucilage of Gum Arabic into a mass." Pilula colocynthidis composita. Compound Colocynth Pills. Ph. Dub. " Take of Colocynth, half an ounce; Hepatic Aloes, Scammony, of each an ounce; Spanish Soap, two drachms ; Oil of Cloves, one drachm. Reduce the aloes, scammony, and colocynth, separately to powder; then beat them together with the oil and soap, with the addition of the syrup into a mass." These compositions are of similar powers. They afford a stronger cathartic than the simple aloetic pill, and accordingly this compound pill is used in constipation, or to obviate habitual costiveness. Two pills are a common dose. Pilula aloes et myrrha. Pills of Aloes and Myrrh. (Pilulae Aloes cum Myrrh. Ph. Lond. Dub.) "Take of Socotorine Aloes, four parts; Myrrh, tw» parts; Saffron, one part. Beat them into a mass witfc PILLS. 277 Simple Syrup." In the formula of the London College, the proportion of sarfron is equal to two parts. In that of the Dublin Pharmacopoeia, a little oil of carraway is added. These pills, under the name of Rufus's Pills, have long been in use, as affording a moderately stimulating cathartic, useful in dyspepsia connected with costiveness; sometimes used also in hypochondriasis, hysteria, and in jaundice. Their dose is ten or fifteen grains. Pilula ammoniareti cupri. Pills of Ammoniuret of Copper. " Take of Ammoniuret of Copper, rubbed into fine powder, sixteen grains ; Crumb of Bread, four scruples ; Water of Carbonate of Ammonia, as much as may be sufficient. Beat them into a mass, which divide into thirty-two equal pills." It is under this form that ammoniuret of copper is given in epilepsy and the other spasmodic diseases in which it has been employed. Half a grain of it is contained in each pill. One pill is given at first, night and morning, and the dose is gradually increased, as far as the stomach and general system will bear it, until a cure is obtained, or the remedy has received a fair trial. Pilula assafoetida composita. Compound Assafoetida Pills. " Take of Assafoetida, Galbanum, Myrrh, of each eight parts; Rectified Oil of Amber, one part. Beat t«hem into a mass with Simple Syrup." These pills afford a stimulating aperient, and foetid antispasmodic, used in hysteria and amenorrhoea, two or three of them being taken at bedtime. Pilula galbani composita. Compound Pills of Galbanum. Pharm. Lond. " Take of Galbanum, an ounce ; Mvrrh, Sagapenum. of each one ounce and a half; Assafcetida, halt an ounce ; Syrup, as much as may be sufficient. Beat them together, and form a mass." PILLS. 278 Pilula myrrh a composita. Compound Pills of Myrrh. Ph. Dub. " Take of Assafoetida, Galbanum, Myrrh, in powder, of each one ounce ; Oil of Amber, half a drachm. Triturate them together, and form them into a mass with Symple Syrup." These compositions, though under different names, are similar to the preceding one. They all form a substitute for the Gum Pills of the older Pharmacopoeias. They are used in the same cases, and in the same dose. Pilula hydrargyri. Mercurial Pill. (Pilula? Hydrargyri, Ph. Lond. Dub.) " Take of Purified Quicksilver, Conserve of Red Rose, of each one ouuce; Starch two ounces. Rub the quicksilver with the conserve, in a glass mortar, until the globules entirely disappear, adding, as there may be occasion, a little mucilage of gum Arabic; then add the starch, and beat, with a little water, into a mass, which is to be immediately divided into four hundred and eighty pills." The formula in the London and Dublin Pharmacopoeias is a little different from this. It prescribes " of Purified Quicksilver, two drachms; Conserve of Red Rose, three drachms ; Liquorice Root in powder, one drachm. Rub the quicksilver with the conserve until the globules no longer appear, then adding the liquorice powder, beat the whole together so as to form a mass." A grain of mercury is contained in four grains of the mass, prepared according to the formula of the Edinburgh College, and in three grains according to the other The trituration of the quicksilver in this preparation was formerly believed to reduce it merely to a state of extreme mechanical division. But there is every reason to believe that an oxidation of the metal is effected, and that the medicinal efficacy of the preparation depends on this oxide. Quicksilver., in its metallic state, being entirely inert with regard to the living system, the activity PILLS. 279 of the preparation itself is a presumption of this ; but it is farther known, that by agitation with atmospheric air, quicksilver affords a portion of a gray powder, soluble in muriatic acid, and which must therefore be regarded as an oxide, metallic quicksilver being insoluble in that acid. This oxidation must be effected more readily when the surface of the metal is extended, and its continuity is divided by the interposition of any viscous matter, and hence the advantage derived from the trituration of it with substances of this kind, in the preparation of the mercurial pill. Different substances have been employed syrup, mucilage, honey and others. The Colleges have now agreed in preferring the Conserve of Rose, it having been supposed that this is superior to the others in facilitating the operation. Much attention is requisite that the trituration be continued until the extension is completed, as on this the efficacy of the pill depends. This is known by rendering the matter a little thinner by the addition of a little water, and extending it by rubbing on a glass plate or on paper, when the globules, if any remain, will be apparent. Starch has been selected by the Edinburgh College to form it into a mass, and is preferable to liquorice powder, as not being liable to become mouldy. This pill is the preparation of mercury that is upon the whole most generally used for obtaining the general action of this metal on the system ; and while it is milder in its operation than some others, and has less determination to the intestinal canal, it is sufficiently active and certain. The common dose, given with the view of inducing the usual mercurial action, is two pills at bedtime and one in the morning, which, in particular cases and habits, requires to be increased. Four or six pills given at once generally excite purging. Pilula opiata, olim Pilulce Thebaic®. Opiate Pills. " Take of Opium, one part; Extract of Lifpiorice, seven parts; Jamaica Pepper, two parts. Mix the opium PILLS 280 and the extract separately, softened with diluted alcohol and beat them into a pulp; then add the Jamaica pepper rubbed to powder, and, beating them well, reduce them to a mass." Pilula saponis cum opio. Pills of Soap with Opium. Ph. Lond, " Take of Hard Opium, rubbed to powder, half an ounce ; Hard Soap, two ounces. Beat them together, until they form one mass." Pilula e stvrace. Pills of Storax. Pharm. Dub. " Take of Purified Storax, three drachms ; Soft Purified Opium, one drachm ; Saffron, the same weight. Beat them together, mixing them thoroughly." The articles which in these compositions are added to the opium, cannot be supposed to have any important effect on its operation ; they serve merely to disguise it; and where it is necessary, which it occasionally is, to conceal the administration of opium from the patient, they afford convenient forms. Even the name sometimes requires to be concealed in a prescription ; and hence the reason of the names given by the London and Dublin Colleges being derived from the trivial ingredients. It is only to be regretted, that the proportion of Opium is not the same in all of them Two pills, or ten grains of the pill of the Edinburgh Pharmacopoeia, contain one frain of opium ; while in the formula of the London and )ublin Colleges, the proportion of opium is larger, five grains or one pill containing one grain. Pilula rhei composita. Compound Pills of Rhubarb. " Take of the Root of Rhubarb, in powder, one ounce ; Socotorine Aloes, six drachms ; Myrrh, half an ounce ; Oil of Peppermint, half a drachm. Beat them into a mass with syrup of orange-peel." This is a moderate laxative much employed, especially in dyspeptic affections, to obviate costiveness, and PILLS 281 stimulate gently the stomach and intestines. Two pills arc taken at bed-time, and operate in general without occasioning any irritation, evacuating the contents ot the intestines, without producing purging. Pilula scillitica. Squill Pills. " Take of the dried Root of Squill, rubbed to a fine powder, one scruple; Gum-Ammoniac, Cardamom Seeds, in powder, Extract of Liquorice, of each one drachm. Beat them with simple syrup into a mass." Pilula en la compos'ita. Compound Sq.iill Pills. Ph. Lond. "Take of the Root of Squill, recently dried, and beat to powder, a drachm; Ginger Root, in powder, Hard Soap, of each three drachms; Gum-Ammoniac in powder, two drachms. Mix the powders together; then beat them with the soap, adding as much syrup as may be sufficient to give the due consistence." Pilule scilla cum zingibers. Pills of Squill with Ginger. " Take of Squill Root in powder, one drachm ; Ginger Root in powder, two drachms; Essential Oil of Anise, ten drops. Triturate them together, and form them into a mass by the addition of soap jelly." Under the form of these compositions, which have long been officinal, and which do not differ materially from each other, squill is often given as an expectorant in dyspnoea and chronic catarrh, two pills being taken morning and evening. Any efficacy they have depend* on the squill. But there appears to be no advantage in reducing so much its activity by the addition of so large a proportion of other matter; and as squill, when long kept, is liable to have its strength impaired, it is perhaps preferable that it should be given under some form of exuffi~ CATAPLASMS. 310 cient. Mix, so as to obtain the consistence of a cataplasm." In the Dublin Pharmacopoeia, it is formed from equal quantities of mustard seed in powder and crumbs of bread mixed with as much wine vinegar as is requireo 1 ; and it is added, that the cataplasm may be rendered more stimulating by the addition of two ounces of horse-radish root, finely scraped. The Mustard Cataplasm, or Sinapism as it is named, is the composition usually applied as a powerful stimulant to the soles of the feet, in typhus, where there is a determination to the head, and in comatose affections. It acts as a very powerful rubefacient; its action is attended with a sense of heat and pain, which soon become urgent, and hence, when applied in a state of coma, the application ought not to be continued too long. It operates on the same principle as a blister, and differs principally in its effect being more quickly obtained, and being more powerfully stimulant to the general system, without producing the same extent, of superficial inflammation. APPENDIX TO VOLUME SECOND. Mineral Waters are complicated in their composition, and, according to the substances with which they are impregnated, produce different effects on the system, and are hence employed to answer different indications. At the same time, they have certain common medicinal relations. They are therefore not easily arranged under the classes of the Materia Medica, when these are established on analogies in medicinal operation. It is also of advantage to give a connected view of their chemical analysis. I have therefore thought it preferable to place them together, and have accordingly referred them to this appendix. The Elastic Fluids that have been employed medicinally, require a similar arrangement, as there is the same difficulty in plating them under the respective classes of medicines; and from the peculiarities in their preparation and mode of operation, the same advantage in giving their history in connection. I have added a few observations on the medical employment of Electricity and Galvanism, to complete the view of what properly belongs to Materia Medica. And, lastly, as connected with the subject, I have subjoined the heads of a lecture, which I have been accustomed to deliver on the doses of medicines, and the rules that regulate extemporaneous prescription. MINERAL WATERS. 312 f. —OF MINERAL WATERS. Waters, which flow at the surface of the earth, are frequently impregnated with foreign matter, so far as to acquire peculiar taste or odour, to be capable of exerting specific chemical actions, or to produce changes in the state of the living system. Such waters are denominated Mineral, it being usually matter belonging to the mineral kingdom which communicates these powers. Important medicinal effects are frequently obtained from mineral waters, arising primarily from the operation of the substances which they hold dissolved, though this is no doubt aided by the state of dilution in which they are administered, the action of the water itself as a dil ient, and by other external circumstances. The chemical analysis, therefore, of these waters is of importance, as determining the principles) in which their active powers reside, and thus enabling the physician to employ them with more advantage and discrimination. Mineral waters, both in a chemical classification, and considered in relation to their medicinal use, may be arranged under four orders : Carbonated Mineral Waters, or those impregnated with carbonic acid gas; Sulphureous Mineral Waters, or those impregnated with sulphuretted hydrogen; Saline Mineral Waters, or those which hold certain neutral salts in solution ; and Chalybeate Mineral Waters, or those, the properties of which depend on an impregnation of iron. These indeed are not perfectly insulated, but. in general, those of one division have a certain relation to those of the others, by being likewise impregnated with one or other of the ingredients which these contain. But still each may be classed according to its predominant ingredient, or that which gives it its most characteristic chemical and medicinal powers. It would be foreign to the object of this outline, to give the minute details connected with the analysis of mineral waters. This properly belongs to a System of MINERAL WATERS. 313 Chemistry. It will be sufficient to point out the general modes of analysis, or rather of discovering their principles, and to add to this chemical view, a brief account of their medicinal applications. I. Carbonated Mineral Waters.—The waters referred to in this class are those which contain carbonic acid gas ; and to bring thenl under the appellation of mineral waters, this must be present in such quantity as to communicate certain sensible qualities. Waters impregnated with free carbonic acirf gas, sparkle when drawn from the spring, or poured into a glass ; they have a taste more or less pungent and acidulous, but become, vapid from exposure to the air. Along with the carbonic acid there may be present, and, indeed, generally are present, portions of saline earthy or metallic matter, chiefly carbonates of lime, magnesia, and iron. But the carbonic acid in excess still communicates the same sensible qualities, modified, particularly with regard to medicinal powers, by these impregnations. Carbonic acid in excess, in a mineral water, is discovered, when present in any considerable proportion, by the qualities above enumerated, communicated to the water. It is also easily distinguished, even when in more minute quantity, by chemical tests. Infusion of litmus receives from the addition of the water a red tint, which is evanescent, disappearing from exposure to the air, and more quickly when heat is applied. And lime water produces a milkiness or precipitation ; the lime, when the water is added in due proportion, forming with the carbonic acid, carbonate of lime, w hich is insoluble. But the turbid appearance is removed, and the transparency restored, either by adding an additional quantity of the mineral water, the excess of carbonic acid thus communicated rendering the carbonate soluble, or by adding a few drops of nitric or muriatic acid, either of which decomposes the carbonate, and dissolves the lime. By the evanescent redness, carbonic acid is discriminated from any other free acid that a mineral water might Vol. II. 41 MINERAL WATERS. 314 hold dissolved ; and by the precipitate formed by lime disappearing from the addition of a larger quantity of the mineral water, or of a little muriatic or nitric acid, the fallacy is guarded against that might arise from any precipitation produced by sulphates that the water might, contain. The quantity of carbonic acid contained in the mineral waters is very various/ Under a common pressure, pure water can absorb its own volume of the gas, but the quantity in any mineral water is generally much inferior to this. Tlfe quantity is discovered by expelling the gas from a given quantity of the water, by heating it gradually in a retort nearly tilled to the neck, receiving the elastic fluid in a graduated jar, over quicksilver, and observing the diminution of volume it sustains, by the introduction of a solution of potash, this giving the volume of carbonic acid gas. Waters highly impregnated with carbonic acid gas are grateful from their pungency, sit light on the stomach, and in a large dose produce even sensibly a degree of exhilaration ; they increase the appetite, and generally have a diuretic effect. They prove useful in dyspeptic affections, from the grateful and moderate stimulus exerted by the carbonic acid on the stomach, aided by the diluent operation of the water, and hence the advantage derived from them in the numerous chronic affections connected with impaired power of the digestive organs. They generally also contain some saline substances, which communicate additional powers, and the operation of these is usually promoted, or at least they are rendered more grateful, by the carbonic acid. Those w hich contain carbonate of soda, as Seltzer water, prove more powerfully diuretic, and are employed with advantage, as palliatives in urinary calculus, and in the painful discharge of urine from other affections of the urinary organs. Those impregnated with iron are more particularly employed in those diseases in which that metal is beneficial. Some of the most celebrated mineral waters of Europe belong to this class, such a* MINERAL WATERS. 315 the Spa, Pyrmont, and Seltzer Water. The Pyrmont contains very nearly its own volume of the gas; ihe Seltzer, more than half its volume; the Spa, rather less than hall the volume: they besides hold dissolved carbonates of soda, lime, arid magnesia ; and the Sua and Pyrmont have a considerable impregnation of carbonate of iron. Their more minute analysis will be found in the table at the end of this article. None of the mineral springs of this country are much impregnated with carbonic acid ; and those which contain any sensible quantity, as the waters of Bristol ami Cheltenham, derive more activity from the presence of other substances. II. Sulphureous Mineral Waters—These waters owe their distinguishing character to an impregnation of sulphuretted hydrogen, and they ate at once recognised by their peculiar foetid smell. They are transparent when drawn from the spring, but become turbid from exposure to the air, and gradually lose their odour. When strongly impregnat d, they redden infusion of litmus, and even in their weakest state give a dark precipitate with solution of nitrate of silver, or acetate of lead, or tarnish the metals. To estimate the quantity of sulphuretted hydrogen gas contained in these waters, various methods have been employed. The gas is not easily expelled entirely by heat, nor is it easily collected, so as to measure it accurately, water absorbing it, and quicksilver decomposing it: it may also have an intermixture of carbonic acid gas, and the proportion of this is not easily ascertained, both gases being absorbed by the same liquids. The mode which has been followed is to decompose the sulphuretted hydrogen, by adding to the water, either highly turning nitrous acid, as long as there is any precipitation of sulphur, fthis precipitation being occasioned by the oxygen of the acid combining with the hydrogen of the sulphuretted hydrogen.) or, according to a method preferred by Kirwan, mixing nitric oxide gas with atmospheric air, in ajar over the water, whew. 316 MINERAL WATERS. nitrous acid is formed, and produces a similar decomposition. The precipitated sulphur is collected on a filter, and from its quantity, the quantity of sulphuretted hydrogen is inferred, .30 grains of sulphur being supposed to be contained in 100 cubic inches of the gas. This estimate, however, of the proportion of sulphur in sulphuretted hydrogen is somewhat uncertain, and the method is liable to fallacy, from the action of the acid becoming weak by its dilution, so as not to precipitate the whole of the sulphur, or, if it be used in excess, from its communicating oxygen, and converting it partially into sulphuric acid The sulphurous mineral waters almost uniformly contain saline substances, which modify their powers From the action of the sulphuretted hydrogen, they are employed more particularly in cutaneous affections; and from the combined action of this the saline matter, which generally has a purgative effect, they are farther used in diseases of the digestive organs, dyspepsia, hypochondriasis, torpor of the intestines, and visceral obstructions ; and also in scrofulous affections. They are also applied locally in cutaneous eruptions, and the warm stdphurous baths have been in particular celebrated for their efficacy under this form of application. The principal sulphurous mineral waters of this country are those of Harrowgate and Moffat: the former have a large proportion of saline matter, muriates and carbonates. Those celebrated on the continent are chiefly the warm sulphurous springs of Aix la Chapelle, and Barege. III. Saline Mineral Waters—Under this class are comprised those waters in which, without any large proportion of aerial matter, various saline compounds, generally neutral, exist. The salts most usually present are sulphates, muriates, and carbonates; and the bases with which the acids forming these are combined are soda, magnesia, and lime. Their analysis is accomplished, first, by detecting, by the eniplo) ment of tests, the acids MINERAL WATERS. 317 present and the bases by which these are neutralized; and, secondly, obtaining the entire salts by evaporation, or by the action of certain re-agents. in these waters, there is often an impregnation of elastic fluid, particularly of carbonic acid, which would modify the results from the application of tests. This, after its nature has been determined by experiment, is expelled by heat, in order to facilitate the farther analysis : and in general also, it is of advantage to reduce the volume of the water by evaporation, as the operation of tests becomes then much more sensible than under a state of great dilution. Sulphuric acid, in any state of combination in a mineral water, is discovered with great delicacy by muriate of barytes, the barytes attracting it, and forming a compound not sensibly soluble, the production of which, therefore, gives rise to a turbid appearance, and precipitation. The only fallacy that requires to be guarded against is, that the same apparent results may be produced by carbonic acid present in the mineral water, either in a free or combined state ; but this is easily discovered by the precipitation or turbid appearance being removed, by the addition of a few drops of nitric acid, or not appearing if this has been added to the mineral water previous to the addition of the muriate of barytes. Other tests of sulphuric acid have been employed, such as superacetate of lead, and nitrate of mercury ; but theseare both less delicate and less accurate. Muriatic acid is detected by nitrate of silver, the oxide of silver combining with the muriatic acid, and forming an insoluble compound, which gives to the water first a bluish white turbid appearance, and ultimately precipitates. This test is extremely delicate, or detects the most minute quantity of muriatic acid, and in any state of combination whatever. But it is liable to fallacies, against which it is necessary to guard. The principal of these arise from the presence of carbonic acid or sulphuric acid, either of these giving rise likewise to milkiness and precipitation on the addition of the so- MINERAL W ATERS. 318 lution of silver. The operation of carbonic acid is prevented by previously adding a little pure nitric arid to decompose any carbonate : that of sulphuric acid can be obviated only by removing it by the previous addition of nitrate of barytes, as long as any precipitation is induced. If, on adding to the transparent fluid, after these preliminary experiments, the nitrate of silver, any milkiness is produced, this indicates the presence of muriatic acid. Sulphuretted hydrogen gives a precipitate with test; but the nature of this is, from its dark colour, sufficiently evident. Carbonic acid, in a combined state, is detected by muriate of barytes producing a turbid appearance, and a precipitation, which are removed by the addition of a few drops of nitric acid. Waters containing any considerable impregnation, either of alkaline or earthy carbonates, sensibly affect the vegetable colours, changing, when there is no excess of carbonic acid, or when this is removed by ebullition, the colour of Brazil wood, which is red, to a tint of blue, or restoring the blue tint of litmus which had been reddened by the addition of a little vinegar. When the water is considerably reduced by evaporation, a sensible effervescence is excited on the addition of an acid ; and during the evaporation, the earthy carbonates are precipitated, while the alkaline carbonates remain dissolved, and are discovered by their power of changing the yellow colour of turmeric to a brown. These acids are usually combined with soda, lime or magnesia ; and to complete the analysis by the application of tests, these bases must be discriminated. Ldme is detected, with the greatest delicacy of effect, by oxalic acid. The acid indeed with which the lime is combined in the water, when evolved by the action of the oxalic acid, is liable to re-act on the precipitate, and retain it in part dissolved; but this may be guarded against by using oxalate of potash. Magnesia is precipitated by the same acid ; but this can scarcely give rise MINERAL WATERS. 319 to any fallacy, as this precipitation takes place very slowly, while that with lime is immediate. Magnesia is precipitated by ammonia partially, and by lime water entirely ; the principal fallacy to which both tests are liable is, that argil is also precipitated by them, and though this earth is not of very common occurrence in mineral waters, it is occasionally found. The best method of distinguishing them is to dry the precipitate, and boil gently a solution of potash on it, this dissolving argil, but leaving magnesia undissolved. Succinate of ammonia, it has lately been discovered, precipitates argil, but not magnesia. In using lime water as the precipitant, it is necessary to guard against the fallacy that may arise from the presence of carbonic acid free or combined, with which the lime may unite, and form a precipitate: this may be avoided by removing any carbonic acid by the previous addition of a little nitric acid. Any sulphuric acid also that may be present ought to be removed by nitrate of barytes, as it might unite with the lime, and give rise to a precipitate of sulphate of lime. Soda, which is the alkaline base almost exclusively found in mineral waters, cannot be discovered by any test, such as that by which we discriminate the preceding ingredients. T he presence of it, therefore, is inferred, when the analysis discovers acids in the water, which are not uncombined, and which, at the same time, can- not be inferred from the application of tests to be in combination with earthy bases. It is also discovered in its state of combination with any of the usual acids by evaporation, carried so far, that its salts are obtained crystallized. By the same method the other compound salts, those having lime, magnesia, or argil, for their base, are discovered, and hence evaporation is always employed in combination with the use of tests in conducting the analysis of a mineral water Different substances separate at different stages of the evaporation, according to their degrees of solubility : the earthy carbonates are usually first precipitated, afterwards the MINERAL WATERS. 320 earthy sulphates, at least the sulphate of lime: the clear liquor poured off and allowed to cool, affords the alkaline neutral salts and sulphate of magnesia by crystallization ; the muriates of magnesia and lime usually remain dissolved in the residual liquor, and by these separations the analysis is facilitated. Advantage is also taken of the powers of alcohol, both as a solvent and as a precipitant, to separate these substances. When the water is reduced to a concentrated state by evaporation, the addition of alcohol throws down certain salts, while others remain dissolved ; and of those which are precipitated, some are thrown down by a small quantity of alcohol, or when the evaporat ion has not been carried far; while others are separated only when the alcohol is added in larger proportion, or when the water is farther evaporated. Thus, sulphate of lime is first precipitated, then carbonate of lime and carbonate of magnesia, afterwards, sulphate of soda and sulphate of magnesia, while the muriates in general remain dissolved. In applying the solvent power of alcohol to facilitate the analysis, the water is evaporated to dryness, and tit is dry matter is submitted to the action of alcohol ; the muriates which are present are in general dissolved, while the sulphates and carbonates remain undissolved. By these operations, too, the quantities of the respective salts contained in a water are determined ; the substances separated being either brought to a certain state of dryness, or being dissolved separately in water and crystallized. The quantities are sometimes inferred, too, by estimation from the precipitates afforded by re-agents; the quantity of sulphuric acid, for example, being determined from the weight of the precipitate of sulphate of barytes, obtained by the addition of muriate of barytes; that of muriatic acid from the weight of the precipitate of muriate of silver, obtained by the addition of nitrate of silver ; and that of lime from the weight of the precipitate of oxalate of lime ; these quantities being inferred according to the composition of these compounds, as they have been determined by the most accurate ex- MINERAL WATERS, 321 peri merit*. In general, these methods require to be combined to insure accuracy, especially with regard to the determination of proportions. At the same time, it may be doubted whether the view, vvhirh has usually been given with regard to the state in which these substances exist in mineral maters, is just. It has been supposed, that they are dissolved in the water in those forms of binary combination in which they are obtaiued by evaporation or precipitation; thai if muriate of soda, lor example, sulphate of magnesia, and carbonate of lime are obtained by these methods, the mineral water held these salts dissolved. Of this, however, there is no proof, and the most correct views of chemical affinity rather lead to the conclusion, that the different acids and different bases exist with their affinities balanced, contributing to mutual neutralization, in simultaneous combination, and that these binary compounds are established only by the exertion of the force pi cohesion, and are therefore actually formed by the processes by which they are obtained. If this view be just, the only conclusion that can strictly be drawn from the analysis is, that certain acids and certain bases exist in the mineral water, and it may appear to be superfluous to attempt to determine the quantities of the binary compounds. Still, as reducing the estimation to a standard, this is as useful as any other mode ; it corresponds more directly with the results of the experiments which have been hitherto made, and we can, if necessary, infer from the quantities thus determined of the secondary compounds, the proportions of the primary principles. Saline Mineral Waters are usually aperient, the substances which tin y hold dissolved being either so far as can be determined inert, s ;ch as the sulphate and carbonate of lime, or being cathartic, as the greater number of the other compound salts. It has always been remarked, too, with regard to them, that their cathartic power is greater than could be supposed from the extent of their saline impregnation, as determined by una- Vol. II. 42 MINERAL WATERS. 322 lysis : a proof of the influence of dilution in the operation of mineral waters. Ihey are usually employed in diseases where it is of advantage to stimulate the digestive system, the intestinal canal, and the secreting organs connected with it, or where advantage is derived from modeiRfp and continued evacuations. Hence their celebrity in the treatment of some forms of dyspepsia and hypochondriasis, chlorosis, chronic hepatitis, jaundice, and in scrofula The most noted saline water is that of Sedlitz ; that of Seltzer, along with a portion of saline matter, has a large impregnation of carbonic acid, and that of Cheltenham, an impregnation both of carbonic acid and iron. When these waters are impregnated with carbonic acid, which they frequently are, they become more grateful, and sit easier on the stomach. When they have an impregnation of iron, they acquire tonic powers, and more efficacy as remedies in amenorrhoea, and the other chronic diseases in which this metal is employed* Sea Water, in strict chemical arrangement, must be regarded as belonging to the class of saline mineral waters, as it holds dissolved merely various neutral salts, chiefly muriate of soda and of magnesia, and sulphate of sorla and magnesia, with a little sulphate of lime. It much exceeds, however, in the extent of impregnation, anv common mineral water: the proportion of saline matter varies in different latitudes, according to the temperature, producing greater or less evaporation, and it is liable to be varied by the discharge of large rivers into the ocean But on an average, the quantity appears to be about k of which, from the experiments of Bergman and Lavoisier, it appears, that about 20 are muriate of soda, 5 muriate of magnesia, 3 sulphates of magnesia and soda, and I sulphate of lime. Its medicinal powers are similar to those of the saline mineral waters; from the extent of its saline impregnation, it is more active as a cathartic, and this renders it more stimulating than fresh w ater as a bath. MINERAL WATERS. 323 IV. Chalybeate Mineral W ; aters. —These owe their Characteristic properties, chemical and medicinal, to an impregnation of Iron. The oxide of iron is ahnost uniformly held dissolved by carbonic acid, the acid being usually in excess ; in a few mineral waters, sulphate of iron is present; but these are rare, and are in general too active to be well adapted to medicinal use. Chalybeate waters have a peculiar styptic taste; they are transparent when taken from the spring, but when exposed for some time to the air, a pellicle forms on the surface, and a quantity, generally minute, of ochry sediment subsides, the water at the same time losing its taste : this change is accelerated by heat. Iron is discovered, with great facility, by chemical tests. Prussiate of potash detects it by the blue colour to which it gives rise ; infusion of galls by the purple colour which it strikes. The latter test is more delicate than the former, and it is much more accurate; the prussiate of potash being always liable to fallacy, from the difficulty of obtaining it free from iron; hence the h> fusion of galls, or rather the tincture of galls, ought always to be preferred. The principal circumstance to be remarked with regard to its operation, is, that the purple colour which it strikes, by the gallic acid and tannin of the infusion combining with the oxide of iron, is liable to be altered in its tint by the presence of other substances: alkaline and earthy carbonates in particular render it violet: neutral alkaline salts appear to deepen the purple colour, and sulphate of lime renders the precipitate at first whitish, and afterwards black. Carbonate of lime has a singular effect: if the iron is in a low state of oxi* dation, it heightens the colour; but when the oxidation is greater, it has the opposite effect; and if the quantity of iron be small, the colour may even not appear on the addition of the test. This fact, discovered by Mr. Phillips, enabled him to explain a singular circumstance with regard to the Bath Mineral Water.—that when newly taken from the spring, and while still warm, it givei a purple, MINERAL WATERS. 324 colour with galls, indicating the presence of iron ; while, alter exposure for a little time to the air, no colour appears, though no oxide of iron has been precipitated. By applying the test ot galls before and alter boiling the mineral water, we are enabled to discover whether the iron is held dissolved by carbonic or sulphuric acid ; the carbonic acid being expelled by the ebullition, and the oxide of iron precipitated, so that after filtration of the liquor when cold, the purple colour does not appear; while the sulphate, though likewise partially decomposed by the ebullition, still so far remains, that a colour not much fainter will be produced. The presence of carbonic or sulphuric acid may also be determined by their usual tests, and sulphate of iron may be obtained by evaporation. The quantity of oxide of iron may be determined from its precipitation, on exposure to the air; the whole or very nearly the whole of it, when it is combined with carbonic acid, being precipitated, in consequence partly of the escape of the acid, and partly of the iron passing to a higher state of oxidation, so that its attraction to the acid becomes weaker. It has also been estimated from the weight of the precipitate, formed by the addition of prussiate of potash ; or, by a more recent and less exceptionable mode, precipitating it by the addition of succinate of soda, and afterwards decomposing the precipitate of succinate of iron, by exposing it to a red heat w ith a little carbonaceous matter, 100 parts of the oxide obtained by the calcination containing about 70 of iron. Chalybeate mineral waters are remedies of considerable activity and power. They act as tonics, increasing the strength of the system, raising the force of the circulation, giving tone to the digestive organs, augmenting muscular vigour, and promoting the excretions. They are of course employed in those diseases in which iron is principally used, amenorrhcea, chlorosis, some states of monorrhagia, leficorrhcea. dyspepsia, scroluia, and various forms of chronic debility. And as iron al- MINERAL WATERS. 325 ways succeeds best when given in small doses, and in a state of considerable dilution, the chalybeate waters afford the best form under which it can be prescribed, that which is at once attended with least irritation, and from which the greatest benefit is obtained. The powers of these waters, too, are often aided by the presence of other ingredients. The impregnation of carbonic acid, when it is present in excess, gives them a grateful stimulant quality, which is exerted on the stomach ; and saline substances communicate to them an aperient power. One of the purest chalybeate waters, as will be perceived from the annexed table, is that of Tunbridge. In the celebrated Spa and Pyrmont waters, the impregnation of carbonic acid is so great, as very materially to modify the action of the iron; and in the Cheltenham water, the quantity of active saline matter is such, that it can scarcely be regarded as a chaly beate. Besides the substances which have been enumerated as forming the preceding classes of mineral waters, there are some principles common to all of them, so as to be occasionally found in those of each class; and there are some also, which are of very rare occurrence, either of which scarcely require more than a concise enumerat ion. Atmospheric air is contained in all water that flows at the surface of the earth, and renders it more grateful and light as drink. It scarcely in its entire state appears to be contained in more than the usual proportion in any mineral water, while in those in which oiher elastic fluids are present in large quantity, it is probably deficient. Neither does it appear that Oxygen gas is ever present in a proportion larger than that in which it exists, as a constituent of the atmospheric air in water. The fact, rather singular, has been established, however, that Mtrogen gas is afforded by mineral springs. It had often been observed, that in the mineral spring at Buxton, a quantity of elastic fluid was discharged with the water, and a portion escaped on exposure from the water itself. MINERAL WATERS. 326 This was supposed to be carbonic acid ; but Dr. Pearson discovered it to be nitrogen gas, mixed with a little atmospheric air, the volume of air amounting to abuut rh of the water. It was afterwards discovered by Dr. Garnet in the mineral waters of Harrowgate. Sulphurous acid ga* has been found in some hot mineral waters in the neighbourhood of volcanoes, but is scarcely to be looked for in anv other siiuation. The Mineral acids have likewise, though rarely, been found uncombined, or at least in excess Sulphate of Argil and Sulphate ot lion sometimes occur, arising probably from the oxygenation of aluminous slate impregnated with sulphuret of iron, through which the water has passed. Muriate of Miniranesr has been detected in minute quantity. Lastly, Silex exists in solution, especially in hot springs. It is deposited abundantly from the water of the Geyser fountain in Iceland It is dissolved in the water of the hot springs of Carlsbad, and Dr. Gibbes found it in the Bath waters. The temperature of Mineral waters gives rise to a very important distinction among them. The greater number are at the average annual temperature of the place where the spring is situated; others are considerably superior to this, or are positively warm. This modifies their powers. The warmth of the tepid waters renders them rather more stimulating when swallowed, a glow of warmth being felt in the stomach, and sometimes the head is slightly alfeeted. Externally applied under the form of the bath, the temperature has even a mare important influence on their operation, than any impregnation they may have. In some celebrated mineral springs, the salutary powers appear to depend principally or entirely on the temperature, and on the water acting as a diluent, as in the warm mineral waters of Bristol, Matlock, and Buxton, and in the cold spring of Malvern. In the following table is presented the results of the analysis of the most celebrated mineral waters. 1 have MINERAL WATERS. 327 arranged them as nearly as possible according to the preceding classes, though there is considerable difficulty witii regard to some of them, which, from the substances they hold dissolved, belong to one class as well as to another. Thus the Spa and Pyrmont waters belong both to the classes of carbonated and chalybeate waters, i have placed them under the former, as the impregnation of carbonic acid is so very considerable, and gives them perhaps their most important properties. Cheltenham water may be placed either as a saline or as a chalybeate water. 1 have given it the former rank, as the saline matter appears to give it its principal activity . To the four established classes I have added a fifth, those of Pure Waters, or waters so free from any foreign matter that their operation must be ascribed to the fluid acting partly by its temperature, and partly as a diluent. In some of these the analysis indicates a certain portion of foreign matter. But the substances are in general not different from those in common spring water, and are in smaller quantity. I have therefore supposed that they may be arranged under this class, nor have they any of the active powers of the others. There is some difficulty in assigning the place of one of the most celebrated mineral waters, the Bath Water. I have placed it, however, at the head of the pure waters, and immediately after the chalybeate waters, as the impregnation of active matter is inconsiderable, and its operation seems principally dependent on dilution and temperature, modified a little perhaps by the tonic quality of the small portion of carbonate of iron. I have inserted the latest analysis of it, that by Mr. Phillips. With regard to the temperature, I have thought it sufficient to add the epithet cold, where the temperature is not above that of the external atmosphere ; where it exceeds this, I have added the precise degrees. The proportions of the ingredients are those contained in a wine gallon of the water. — ~— " ~~7 ' | Sul- | i /- ' i hT ! S .Sulpha- fcrbo- Sul- phate Sul Mori- a =g waters. 3 .j ,C retted Cnrhi - ate of Carbo- phnte of phate Muri- ate of a S"« jacid gas h vtJ| 0 . nate oi viag- nate of of Mag- of ale of Mag- Muriate Oxide of " 3 ? j gen gas. Soda esia. Lime. Soda, nesia Lime Soda, nesia. of Lime Iron. I ... . . .... 8 rs " cub. in. cub. in. grain.- rams, grains, grains grains, grains grarns grams, grains, grams. t C Seltzer, 138 32 40 24 HO . Cold. Carbo- \ Pyrmout, 208 SO 34.8 44.5 68.6 12 4 4.5 Ctrtd. Dated, j Spa, 104 11.7 35,3 11 7 1 37 4.5 Cold, j C Carlsbad, 32 to 50 39 12 70 34.6 0.125 2 5 165° s . ( Hanowgatej 7 8 19 5.5 18.5 10.5 615.5 91 13 Cold, j , S MofTat, 4 5 10 36 fold. \ p u " S Supersul- . %jmn \ leous. /AixleChap. phireued 90 38 40 143° I J- I hydrogen. } fSedlitz, j j 8 21 67 1444 41 1 365 Cold. Saline / Cheltenham, 12. 30 3 3 12.5 480 40 5 12.5 5 Cold \ Plombieres, 4 4 1 4 7 0.5 2 6 n . , (Tunbridge, 5 10.6 1.25 0 5 2.2 1 Cold. Chaly- ) b Sulphate of beate. ) Brighton, 18 32.7 12.; 6 bon. 1 12 Cold, v i 1 1.2 fBath, 9 6 6 4 12 72 26.4 .016 16 116 | Buxton, 2 10 5 2.5 1.7 0 25 82° Pure. <{ Bristol, 30 13.5 11 2 11.7 4 7 25 74° I Matlock, 66 c I Malvern, Cold. < MINERAL WATERS. 329 The practicability of imitating the mineral waters has engaged the attention of chemists. With regard to me active saline waters, it is easily done, by dissolving the due proportions of the compound *alts in water corresponding to the analysis of the water designed to be imitated. We may also impregnate the solution with carbonic acid gas, and even with sulphuretted hydrogen ; and by the medium of carbonic acid, it might receive an impregnation of iron. Directions for conducting these processes have been given by Bergman. But in all these cases, there will be wanting the confidence on the part of the patient in the efficacy of the artificial water, which, if not necessary to its success, is at least requisite to its continued and regular use: the external advantages too, attending a visit to a mineral spring, may not always be obtained. Hence these artificial waters designed as substitutes for the natural ones, have never been established in use. Water, impregnated with carbonic acid, with the addition of an alkaline carbonate, which is now in general use, may be considered as operating on a similar principle ; and to this super carbonated sodti, or super-carbonated potash water, a small quantity of any of the purgative salts is often added with advantage, communicating to the water an aperient quality, while the taste of the salt is covered, and it is rendered more grateful to the stomach. Vol. lh 330 JJ. OF THE GASES EMPLOYED AS REMEDIES. Substances existing in the aerial form might a priori be supposed capable of producing important effects on the system, as by respiration they are brought to act directly on the mass of blood, and induce in it chemical changes. They occasion too immediate and important alterations in the functions of life, some of them producing the highest excitement, others occasioning depression and exhaustion of power. Though the expectations that were at one time formed, with regard to their medicinal efficacy, have not been realized, an-;ris Sulphur sublimatum Sulphur sublirnatum zinci Oxidum zinci Zinci oxidum Hepar sulphuris Sulphuretum potasssrj Potassa* sulphuretum Hiera picra Pulvis aloes cum canella Hydrargyrus acetatus Acetis hydrargyri calcinntus Hydrargyri oxidum rubrum muriatus corrosivus Murias hydrargyri oxymurias mitis Sub-murias hydrargyri sub-murias prsecipitatus praecipitatus njtratus ruber Oxidum hydrargyri per acidum nitricum nitrico-oxidum Vol. II. 46 TABLE OF CHANGED NAMES 354 OLD NAMES. NAMES IN THE ED. PH. NAMES IN THE LOND. PH. Hydrargyrus praecipitatus cinerius Oxidum hydrargyri cinereum Hydrargyri oxidum cinereum sulphuratus niger Sulphuretum hydrargyri nigrum sulphuratus ruber sulphuretum rubrum vitriolatus rlavus Sub-sulphas hydrargyri flavus Infusum amarum Infusa gentianae compositum Infusum gentianae compositum rosarum rosae galicae rosas Julepum e camphora Mistura camphorae Kali Potassa Potassa Lac sulphuris Sulphur praecipitatum amigdalae Emulsio amigdalae Misturae amigdalae ammoniaci ammoniaci assafoetidae assafoetidae guaiaci guaiaci Laud mum liquidum Tinctura opii Tinctura opii Linimentum anodynum Tinctura saponis cum opio aqua; calcis Oleum lini cum calce opiatum Tinctura saponis cum opio saponaceum saponis Linimentum saponis compositum volatile Oleum ammoniatum ammoniae sub-carbonatis Lithargyrus Oxidum plumbi semi-vitreum Plumbi oxydum semivitreum Lixivii Potassa Potassa Lixivium causticum Aqua potassae Liquor potassae tartari sub-carbonatis TABLE OF CHANGED NAMES. 355 0L» NAMES. NAMES IN THE ED. PH. NAMES IN THE LOND. PH. Magnesia alba Carbonas magnesia; Magnesia; carbonas usta Magnesia M ignesia vitriolata Sulphas magnesias Magnesias sulphas Mel iEgyptiacum Linimentum asruginis rosaceum Mel rosas acetatum Oxymel Mercurius Hydrargyrus Hydrargyrus calcinatus Hydrargyri oxidum rubrum corrosivus sublimatus Murias hydrargyri oxymurias ruber ) Oxidum hydrargyri rubrum per aci- nitrico-oxydum praecipitatus ruber $ dum nitricum dulcis sublimatus Sub-murias hydrargyri sub-murias emeticus flavus Sub-sulphas hydrargyri praecipitatus albus Hydrargyrus praecipitatus Minium Oxidum plumbi rubrum Natron Soda Soda Nitrum Nitras potassae Potassae nitras Oleum teribinthinae Oleum volatile pini Oleum teribinthinae Oxymel asruginis Linimentum aeruginis Philonium Londinens? Confectio opii Pilulae cupri Pilulee ammoniareti cupri gummosa; Pilulae galbani composita r*fi aloes cum myrrha aloes cum myrrha 356 TABLE OF CHANGED NAMES, OLD NAMES. NAMES IN THE ED. PH. NAMES IN THE LOND. PH. Pilulae thebaicae Pilulae aloes opiatae Pilule? saponis cum opio Potio cretacea Potio carbonatis calcis Mistura cretae Pulvis antimonialis Oxidum antimonii cum phosphate Pulvis antimonialis calcis Pulvis e bolo compositus cum opio Pulvis creta? compositus cum opio cretaceus Pulvis carbonatis calcis compositus creta compositus doveri ipecacuanha; et opii ipecacuanha; compositus sternutatorius asari compositus stypticus sulphatis aluminee compositus Resina alba Resina pini Rubigo ferri praeparata Carbonas ferri praeparatus Saccbarum saturni Acetis plumbi Plumbi super-acetas Sal absinthii Carbonas potassae Potassa: sub-carbonas alkalinus fixus fossilis sodae &o« ; aj sub-carbonas alkidinus fixus vegetabilis potassae Pot.tssa? sub-carbonas ammoniacus Murias ammoniae Ammoniae murias volatilis Carbonas ammoniae carbonas catharticus amarus Sulphas magnesia; Magnesia sulphas glauberi sodae Soda sulphas cornu cervi Carbonas ammonia; Ammonia carbonas diureticus Acetis potassae Potassa acetas glauberi Sulphas sodae Soda? sulphas mannus Murias sodae murias Hiartis Sulphas ferri Fern sulphas TABLE OF CHANGED NAMES. 357 OL» NAMES. NAMES IN THE ED. PH. NAMES IN THE LOND. PH. Sal polycrestus Sulphas potassa; cum sulphure rupellensis Tartris potassa; et sodas Soda tartarizata tartari Carbonas potassae Potassa; sub-carbonas Saturni extractum I iquor plumbi acetatis Soda purificata ' sodae Sodae sub-carbonas muriata 3Iurias sodae muri as phosphorata Phosphas sodae tartarisata Tartris potassae et sodae Soda tartarizata vitriolata Sulphas soda; Sodae sulphas Spiritus aetheris vitriolici iEther sulphuricus cum alcohole Spiritus aetheris sulphurici ammoniae Alcohol ammoniatum ammonias aromaticus aromaticum aromaticus foetidus foetidum foettdus camphoratus Tinctura camphorae camphorae cornu cervi Aqua carbonatis ammonias Liquor ammonias carbonatis mindereri acetitis ammoniae acetatis nitri dulcis Spiritus aetheris nitrosi Spiritus aetheris nitrici slauberi Acidum nitrosum salis ammoniaci Aqua ammoniae Liquor ammoniae marini glauberi Acidum muriaticum Acidum muriaticum vinosus camphoratus Tinctura camphorae Spiritus camphorae rectificatus Alcohol rectificatus tenuior dilutum tenuior ritrioli dulcis iEther sulphuricus cum alcohole aetheris sulphurici volatilis aromaticus Alcohol ammoniatum aromaticum ammoniae arom uicus fostidus fetidum fbetitidus TABLE OF CHANGED NAMES. 358 •LB NAMES. NAMES IN THE ED. PH. NAMES IN THE LONB. PH. Succi ad scorbutieos Succus cochlearias compositus Sulphur antimonii praecipitatum > Sulphuretum antimonii praecipita- Antimonii sulphuretum praecipitatum auratum antimonii $ turn Sulphuris flores Sulphur sublimatum Sulphur sublimatum Syrupus balsamicus Syrupus toluiferae balsami Syrupus tolutanus e meconio papareris somniferi papaveris Tartarus crudus Super-tartris potassa; impurus Tartari crystalli potassa; Potassa; super-tartras Tartarus emeticus Tartris antimonii Antimonium tartarizatum Tartarum solubile potassae Potassa; tartras vitriolatum Sulphas potassae sulphas Tinctura aloes vitriolata Tinctura aloes aetherea amara gentianae composita Tinctura gentianae composita aromatica cinnamomi composita cinnamomi composita cantharidum meloes vesicatorii lyttae ferri muriatis ferri ferri muriatis foetida ferula; assa»ibetidae assasfcetida; guaiacina volatilis guaiaci ammoniata guaiaci ammoniata japonica mimosae catechu catechu martis muriatis ferri ferri muriatis melampodii hellebori nigri hellebori nigri opii camphorata camphorae composita rhei amari rhei et gentiana rosarum Infusum rosarum Infusum rosae sacra Vinum aloe§ socotorinse Viaum aloes TABLE OF CHANGED NAMES. 359 OLD JNAMEJ. NAMES IN THE ED. PH. NAMES IN THE LOND. PH. Tinctura thebaica Tinctura opii Tinctura opii tolutana toluiferse balsami Valeriana; volatilis Valeriana; ammoniata Trochisci arabici Trochisi gummosi Turpethum minerale Sub-sulphas hydrargyri flavus Tutia Oxidum zinci impurum Unguentum album Unguentum oxidi plumbi albi basihcum flavum resinosum Ceratum resina; flavae cceruleum hydrargyri Unguentum hydrargyri citrinum nitratis hydrargyri nitratis epispasticum fortius pulveris meloes vesica- Ceratum lyttae torii mitius infusi mel. vesicat. saturnimum acetitis plumbi Ceratum plumbi super-acetatis Vinum amarum Vinum gentianae compositum antimoniale tartritis antimonii Liquor antimonii tartarizati chalibeatum Vinum ferri Vitriolum album Sulphas zinci Zinci sulphas cceruleum cupri Cupri sulphas viride ferri Ferri sulphas Vitrum antimonii Oxidum antimonii cum sulphure vitriricatum Zincum ustum Oxidum zinci Zinci oxidum ritriolattlm Sulphas zinci sulphas TABLE OF CHANGED NAMES 360 TABLE II. NAMES IN THE ED. PH. NAMES IN THE LOND. rH. OLD NAMES- Acetis plumbi Plumbi super-acetas Saccharum saturni potassae . Potassa; acetas i Sal diureticus j Lixiva acetata Acidum benzoicum Acidum benzoicum Flores benzoini nitrosum dilutum Acidum nitricum dilutum Aqua fortis sulphuricum sulphuricum Acidum vitriolicum aromaticum i Acidum vitrioli aromaticum Sa * a lk rt l> nus fixus vegetabilis I tartari sodae Sodae sub-carbonas $ Sal alkalinus fixus fossilis ( Soda purificata zinci impurus Calamina praeparata Lapis calaminaris Decoctum guaiaci compositus Decoctum lignorum Electuarium aromaticum Confectio aromatica* Confectio cardiaca cassia sennae sennae Electuarium lenitivum catechu Confectio japomca opiatum opii Electuarium thebaicum Emplastrum meloes vesicatorii Emplastrum lyttae Emplastrum vesicatorium oxidi ferri rubri roborans plumbi semivitrei plumbi commune resinosum resmae adhassivum simplex cerae cereum Emulsio amygdalae communis Mistura amygdalae Emulsio communis Murias ammoniae Ammoniae Murias Sal amoniacus et ferri Ferrum ammoniatum Flores Martiales antimonii Butyrum antimonii Vol. II. 47 TABLE OF CHANGED NAMES. 362 NAMES IN THE ED. PH. NAMES IN THE LOND. PH. OLD NAMES. Murias hydrargyri Hydrargyra oxymurias Hydrargyrus muriatus corrosivus sodas Sodas murias * Sal marinus Nitras argenti Argenti nitras Causticum lunare potassae Potassae nitras Nitrum Oleum ammoniatum Linimentum ammoniae Linimentum volatile lini cum calce aquae calcis sulphuratum Oleum salphuratum Balsamum sulphuris Oxidum antimonii cum phosphate Pulvis antimonialis Antimonium calcareo-phosphoratum calcis Oxidum antimonii cum sulphure per Croc ;s antimonii, vel crocus metalnitratera potassae lorum Oxidum antimonii cum sulphure Vitrium antimonii vitnficatum Oxidum ferri nigrum Ferri squamae rubrum Ferrum vitriolatum ustum hydrargyri per acidum nitri- Hydrargyri nitrico-oxydum Hydrargyrus nitratus ruber cum hydrargyri cinereum oxidum cinereum praecipitatus cinereus plumbi album Plumbi sub-carbonas Cerussa rubrum Minium semivitreum oxydum semivitreum Litb irgyrus zinci Zinci oxydum Fiores zinci impurum Tutia TABLE OF CHANGED NAMES. 363 NAMES IN THE ED. PH, NAMES IN THE LOND. PH. OLD NAMES. Phosphas sodas j Soda phosphorata Pini abietis resini Pix arida Pix Burgundica balsameae resini Terebinthina canadensis Balsamum canadense laricis oleum Oleum terebinthina; Oleum terebinthinae Potassa Potassa ( Alkali fixum vegetabile f Causticum commune acerrimum cum calce Potassa cum calce Causticum commune mitius Potio carbonatis calcis Mistura cretse Potio cretacea Pulvis carbonatis calcis compositus Pulvis cretae compositus Pulvis cretaceus Soda Soda Alkali fixum fossile Solutio sulphatis cupri composita Aqua stiptica Spiritus aetheris nitrosi Spiritus aetheris nitrici Spiritus nitri dulcis Sub-acetas cupri ./Erugo JSrugo aeris sub-murias hydrargyri Hydrargyri sub-murias $ Oalometas { Hydrargyrus Muriatus mitis Sub-sulphas hydrargyri flavus Turpethum minerale Succus spissatus momordicae elaterii Elaterium Sulphas aluminae Alumen Alumen cupri Cupri sulphas Vitriolum cceruleum ferri Ferri sulphas $ Sal martis I Vitriolum viride magnesiae Magnesias sulphas Sal catharticus amarus pot ssas Potassae sulphas Tartarum vitriolatum potassae cam sulphure Sal polychrestus sodae Sodae sulphas glauberi TABLE OF CHANGED NAMES. 364 NAMES IN THE ED. PH. NAMES IN THE LOND. PH. OLD NAMES Sulphas zinci Zinci sulphas Vitriolum album Sulphur sublimatum Sulphur sublimatnm Flores salphuris Sulphuretum antimonii Antimonii sulphuretum Antimonium antimonii praecipitatum sulphuretum praecipitatum £ Sulphur antimonii pracipitatum ( ¦uratinn antfcnonii hydrargyri nigrum iEthiops mineralis rubrum Hydrargyri sulphuretum rubrum Cinnabaris fa titia potassa? Potassae sulphuretum Heparsulphuris Syrupus toluiferse balsami Syrupus tolutanus Syrupus bals irnicus Super-tartris potassae Potassae super-tartras Tartari cryst.dli Tartris antimonii Antimonium tartarisatum Tartarus emeticus potassae Potassae tartras Tartarum solubile potassae et sodae Sofia tartarizata Sal rupellensis Tinctura benzoes composita Tinctura benzoini composita Balsamum traumaticum camphorae Spiritus camphorae Spiritus vinosus camphoratus muriatis ferri ferri muriatis Tinctura martis opii ammoniata camphors? composita Elixir paregoricum saponis Linimentum saponis Linimentum saponaceum saponis cum opio S opiatum f anodynum Unguentum nitratis hydrargyri Unguentum hydrargyri nitratis Unguentum citrinum acetitis plumbi Ceratum plumbi super-asetatis saturninum pulveris meloes resieft- lyttae epispasticum fortius torii resinosum resinae basilicum flavum ENGLISH INDEX. A. Page Acetic acid i. 52, ii. J18 Acetite of ammonia i. 311 ii. 1 3 of lead i. 224, ii. 251 of potash, i. 293, ii. 157 of quicksilver ii. .. confection $ u ' powder ii. 262 sulphuric acid ii. 137 tincture ii. 70 Arrow-root powder i. 383 Arsenic i. 180', 37X oxide prepared ii. 259 solution ii. 259 Arseniate of potash i. 181, ii. 260 ENGLISH INDEX. 366 Page Asarabacca i. 256, 337 Assafcetida i. 156, 284 Astringents i. 211 Attraction, chemical i. 72 Azote i. 8 B Balsam i. 46 Balsam of Canada i. 303 of Copaiva i. 303 of Gilead i. 329 of Peru i. 327 ofTolu i. 328 Barbadoes tar i. J 55 Bark, Peruvian i. 188 Barytes i. 17, 183 Benzoic acid i. 51, ii. ' 20 Benzoin i. 328 Bismuth i. 182 Bistort i. 230 Bitter apple i. 273 principle i. 55 Blessed thistle i. 202 Blistering plaster ii. 306 Bole, Armenian i. 218 Boracic acid i. 26 Borax i. 355 Broom i. 302 Bryony i. 273 Buckthorn i. 274 Burgundy pitch i. 343 plaster ii. 308 C Cabbage tree bark i. 376 Cajeput oil i. 159 Calamine prepared ii. 254 cerate ii. 296 Calcination i. 74 Calomel i. 277, 314, ii. 228 Caloric i. 68 Camphor i. 42, 118, 316 mixture ii. 24 Camphorated acetous acid ii. 63 emulsion ii. 22 liniment ii. 68 oil ii. 114 spirit ii. 68 Page Canella i. 2Q4 Cantharides i. 305, 34l Capsicum i. 206 Caraway i. 209 Carbon i. 10 Carbonate of ammonia i. 312 ii. 167 of iron precipitated ii. 212 of iron prepared ii. 212 of lime i. 220,358 prepared ii. 178 of magnesia ii. 182 of potash ii. 153 of soda ii. 163 of zinc prepared ii. 254 Carbonic acid i. 25, ii. 335 Carburetted hydrogen gas N ii. 337 Cardamom, smaller i. 209 Cascarilla i. 197 Cassia bark i. 204 buds i. 204 purging i. 266 Castor i. 153, 284 oil i. 267 Cathartics i. 257 Cataplasms ii. 309 Catechu i. 232 Caustic, common i. 368, ii. 157 lunar i. 369, ii. 193 Centaury i. 201 Cerates ii. 286 Ceruse i. 223 Chalk, prepared ii. 178 potion ii. 25 Chamomile i. 200, 255 Cherry-tree laurel i. 149 Cinnabar ii. 249 Cinnamon i. 203 water ii. 98 Citric acid i. 50, 350, ii. 122 Citrate of ammonia i. 312 Cloves i. 206 Colocynth i. 273 ENGLISH INDEX. 367 Page Colomba i. 198 Combination i. 64 Concentration i. 76 Confections ii. 373 Conserves ii. 13 Contrayerva i. 196 Copaiba balsam i. 202 Copper i. 179, 221, 252 preparations of ii. 209 Coriander i. 210 Cowhage i. 374 Crabs claws, prepared > i. 359 stones $ ii. 178 Cream of tartar i. 279, 293 Crocus of antimony ii. 201 Crystallization i. 77 Cubebs i. 208 Cucurbit i. 76 Cumin i. 210 plaster ii. 307 D Decoction i. 59, 74 Decoctions ii. 37 Decomposition i. 69 Deflagration i. 74 Demulcents i. 378 Dephlegmation i. 76 Diaphoretics i. 306 Digestion i. 74 Dill-seed i. 210 Diluents i. 387 Distillation i. 75 Distilled waters ii. 95 spirits ii. 100 Diuretic salt ii. 157 Diuretics i. 288 Dover's powder i. 315, ii. 264 Doses of medicines ii. 345 Dxagons blood i. 235 E Earths i. 15 Elaterium i. 273 Elder rob ii. 19 ointment ii. 299 Electricity ii. 339 Electuaries ii. 266 Page Elutriation i. 71 Emetics i. 236 Emmenagogues i. 282 Emollients i. 388 Emulsions ii. 21 Escharotics i. 367 Epispastics i. 338 Epsom salt i. 278 Errhines i. 334 Ether sulphuric i. 57,116, ii. 138 nitric ii. 145 Euphorbium i. 337, 343 Evaporation i. 75 Expectorants i. 319 Extracts i. 60 ii. 83 Extraction i. 74 Extractive matter i. 46 F Fecula i. 37 Fennel, sweet i. 210 Fermented liquors i. 114 Fern, male i. 376 Fixed oils ii. 20 Flowers of benzoin ii. 120 Fluoric acid i. 26 Foxglove i. 138, 297, 324 Fusion i. 74 G Galbanum i. 157 Gallic acid i. 49 Galls i. 229 Galvanism ii. 341 Gamboge i. 276, 377 Garlic i. 325, 344 Gentian i. 200 Ginger i. 208 Glass of antimony ii. 194 Glaubers salt i. 278, ii. 166 Gluten i. 38 Granulation i. 71 Guaiac i.316 Gum i 35 Gum ammoniac i.326 arable i. 380 plaster i. 304 resins i. Cl 368 ENGLISH INDEX. Page Gum tragacanth i. 380 troches ii. 285 resins, preparation of ii 7 H Hartshorn i. 384 burnt ii. 9 oil of i. 119 spirit of ii. 169 Hedge hyssop i. 802 Hellebore, black i. 272 white i. 337 Hemlock i. 135 Hepatized ammonia ii. 174 Henbane, black i. 133 Honey of borax ii. 56 of colchicum ii. 57 clarified ii. 56 of rose ii. 57 of squill ii. 57 Hop i. 148 Horehound i. 202 Horse chesnut i. 336 radish i. 333 Hydrogen gas i. 9. ii. 334 carbonated ii. 337 Hydro-sulphuret of ammonia i. 253, ii. 174 Hyper-oxygenated muriat of potash i. 185, ii. 127 Hyssop i. 211 I Indian pink i. 376 Infusion i. 58, 74 Infusions ii. 27 Ipecacuan i. 253, 323 Iron i. 174, 220, 285, 374 preparations of ii. 211 Isinglass i. 385 J Jalap i. 271 Japonic confection ii. 271 infusion ii. 30 Juices ii. 14 inspissated ii. 15 Juniper i. 302 Page K Kermes, mineral ii. 200 Kino i. 233 L Laudanum ii. 75 Lavender i. 336 Lead i 222 acetate of ii. 25l Lemon i. 203, 350 Lenitive electuary ii. 270 Leopard's bane i. 146 Lettuce, strong-scented i. 145 301 Levigation i. 70 Ley i. 74 caustic ii. 156 Ligneus fibre i. 53 Lime i. 16, 183, 218, 358, 367 water ii 180 Liniment of ammonia ii. 113 Liniments ii. 286 Lintseed i. 381 oil with lime ii 287 Liquorice i. 382 Liquorice extract ii. 86 Litharge i. 223 plaster ii ;02 Lithontriptics i. 3t>0 Liverwort i. 384 Lixiviation i. 74 Logwood i. 231 M Mace i. 205 Maceration i. 74 Madder i. 286 Magnesia i. 16, 269, 359 calcined ii. 183 Mahogany i. 198 Malic acid i. 50 Manna i. 265 Marjoram i. 336 Marsh mallow i. 381. Mastich i. 235 Measures i. 79 Mercury i. 164, 285 Mercurial ointment i. 169, ii.290 ENGLISH INDEX. 369 Page Mercurial pills ii. 278 Met dlic preparations ii. 193 Minims i. 79 Minium i. 223 Monks-hood i. 13 v Mixtures ii. 23 Mucilage i 35 Mucilages ii. 35 Muriate of ammonia i. 313 and iron ii. 217 of antimony i. 369 ii. 202 ofbarytes ii. 176 of quicksilver i. 377 ii. 225 of soda i. 280 Muriatic acid i. 24, ii. 124 Musk i. 152 mixture, ii. 26 Mustard i. 256, 343 cataplasm, ii. 309 Myrrh i. 326 N Norcotic principle i. 55 Narcotics i. 103 Nightshade, deadly i. 134 woody i. 301 Nitrate of potash i. 294, 355 silver ii. 193 Nitre i. 294 Nitric acid i. 24, 184, ii. 133 Nitrogen i. 8 Nitrous acid ii. 32 diluted ii. 133 oxide ii. 332 Nutmeg i. 205 O. Oak bark i. 229 Oil expressed i. 40, ii, 20 volatile i. 41, ii. 105 Oily preparations ii. 113 Ointments ii. 286 Olive oil i. 375, 385 Opiate electuary ii 272 powder ii. 264 Opium i. 121, 315 Vol. II. 48 Page Opium, preparation of ii. 7 Orange i. 202, 352 Orris i. 336 Oxalic acid i. 51 Oxides i. 28 Oxide of antimony with phosphate of lime ii. I96 of antimony with sulphur by nitrate of potash i. 201, ii. 201 of antimony with sulphur vitrified ii. 194 of arsenic i. 371 of iron purified ii 211 214 of quicksilver gray ii. 239 by nitric acid ii. 2 0 of zinc ii. 255 Oxygen gas i. 6, ii. 431 Oxymels ii. 57 0\y-muriatic acid ii 127 Oxy-muriate of potash i. 185 ii. i27 P Paregoric elixir ii. 79 Pellitory i. 332 Peppermint i. 211 Pennyroyal i. .'11 Pepper, black i. 207 Guinea i. ?06 Jamaica i. 208 long i. 207 Peruvian bark i. 188 Phosphate of soda i, 280, ii. 165 Pills ii. 274 Pimento i. 208 Pink, Indian i. 376 Plasters ii. 302 Poison oak i. 147 Poppy, white i J 21 Potash i. 19, 292, 356, 365 ii. 156 water of ii. 54 with lime ii. 157 Potassium i. 20 Powders ii. 267 ENGLISH INDEX. 370 Page Precipitation i 77 Proof spirit ii 104 Prussic acid i. 52 Pulps, extraction of ii. 5 Pulverization i. 71 Q Quassia i. 200 Quicksilver i. 164,285,331 calcined ii. 246 purified ii. 222 with chalk ii. 245 sulphur ii. 244 red precipitate 240 white Precipitate ii. 248 muriate of i. 370, 173, ii. 225 sub muriate of ii. 228, 233 sub-nitrate i. 370, ii. 240 sulphurets of ii. 244, 249 acetate of 223 gray oxide of 236 red oxide of 246 yellow sub-sulphate 242 R Rectification i. 76 Refrigerants i. 345 Resin i. 44 white and yellow i. 304 Resinous ointment ii. 288 plaster ii. 303 Rhododendron i. 147 Rhubarb i. 270 Rochelle salt ii. 164 Rose, red i. 231 Rosemary i. 336 llubefacients i. 338 Rue i. 286 Rust of iron, prepared ii. 211 S Sacred elixir ii. 77 Saffron, tincture ii. 59 English i. 158 Page Saffron, meadow i. 301 Sagapenum i. 157 Sage i. 319 Sago i. 383 Sal-ammoniac i. 313 polychrest ii. 159 Saline preparations ii. 115 Salop i. 383 Salt of amber ii. lio of hartshorn i. 199, ii. 169 of tartar ii. 152 Salts, neutral i. 26 Sarsaparilla i. 382 Sassafras i. 318 Saturnine ointment ii. 295 Savine i. 287, 371. Scammony i. 276 Sea oak ii. 10 Sedatives i. 135 Seneka 325 Senna 269 Si.dagogues 330 Silex 15 Silver, nitrate of i. 163, ii. 193 Simarouba i. J 99 Sinapism i. 343 Snake-root, Virginian i. 195 Soap 366 liniment ii. 77 plaster 305 Soda 20, 357, 366 carbonate of ii. 162, 163 Sodium i. 21 Soluble tartar ii. 160 Solution i. 72 of acetite of zinc ii. 257 muriate of barytes 178 muriate of lime 181 sulphate of zinc 257 sulphate of copper, compound 210 Spanish fly i. 305, 3 U Spearmint 211 .spermaceti 386 Spirit of ammonia ii. 171 aromatic 172 foetid 173 mindererus ii. 173 ENGLISH INDEX. 371 Page. Spirit of nitrous ether i. 296 ii. 148 of vitriolic ether 143 Spirit, ardent i. 110, ii. 104 Spirits, distilled 100 Sponge, burnt 9 Squill i. 255, 296, 324 dried ii. 5 pills 281 vinegar 63 Starch i. 384 Storax 329 Storax purified , ii. 7 Strontites i. 17 Sub-acetite of copper 370 Sub-muriate of mercury ii. 228 and ammonia 248 Sub-nitrate of mercury i. 370 ii. 240 Sub-sulphate of mercury 243 Sublimation i. 76 Sugar 39 Sugar of lead ii. 251 Sulphate of alumine i. 218 dried ii. 175 copper i. 369 iron ii. 213 dried 214 magnesia i 277 potash i. 278, ii. 158 with sulphur ii. 159 soda i. 278, ii. 166 zinc 256 Sulphur i. 11,268, 315 ointment ii. 298 precipitated 11 sublimed, washed 11 Sulphurated oil 114 Sulphuret of antimony prepared 194 Sulphuret of antimony precipitated ' 199 sulphuret of potash 160 quicksilver 244 red 249 Sulphuric acid i. 23, 216 Page. Sulphuric acid aromatic ii. 137* diluted 13G ether 138 Super-carbonate of potash i. 365 ii. 153 soda i. 366 ii. 162 Super-sulphate of argil and potash i. 218, 368 Super-tartrate of potash i. 279 293, 354 Synthesis i. 6 Syrups ii. 48 T Tamarind i. 266, 353 Tannin 48 Tansy 376 Tar ointment ii. 297 mineral i. 155 Tartar, crystals of, 279, 293, 354 emetic ii. 204 Tartaric acid i. 51 Tartrate of antimony ii. 'i04 potash & soda i. CO ii. 164 potash i. 279, ii. 160 Thorn-apple 145 Tin 375 powder ii. 258 Tinctures 64 Tobacco i. 143,256,281, 301, 324, 334, 337 Tonics 160 Tormentil 230 Trefoil 202 Trituration 71 Troches ii. 283 Turpeth mineral 243 Turpentine i. 281, 304 Cyprus 305 oil of 304, ii. 112 Tutty, prepared 254 V Valerian wild i. 158 Vegetable analysis 28 Vegetables, preparation of ii. 6 ENGLISH INDEX 372 Page. Verdigris i. 252, 370 Vinegar i, 350 distilled ii. 116 Vinegars medicated 62 Vitriol, blue i. "69 green ii. 213 white 256 Vitriolic acid i. 212 diluted ii. 136 ether 138 Volatile liniment i. 344, 113 oils ii. 105 Vomica nut i. 148 W Wake robin 333 Water distilled ii. 97 of acetite of ammonia i. 3> 1, 173 ammonia ii. 170 ammouiated copper 210 carbonate of ammonia 168 potash 157 sulphuret of potash 161 Page. Water of sulphuret of ammonia 175 super-carbonate of potash ii. 153 of soda 164 Wax 386 ointment ii. 288 plaster 302 Weights 1.78 Whortleberry 231 Wine 114 of tartarised antimony ii. 208 Wines, medicated 58 Wolfsbane i. 135 Wormseed 375 Wormwood 201 Z Zedoary 208 Zinc i, 177, 220, 252 oxide of ii. 255 carbonate of 254 sulph ite of 256 acetate of 257 LATIN INDEX. A Page Absynthium vulgare i. 258 Acetis ammonia; i. 311, ii. 173 hydrargyri 23 plumbi i. 224, ii. 251 potassa; 293, 157 zinci i. 22i., ii. 257 Acetum 3 >3 aromaticum ii. 63 distillatum 116 scillas maritime; 63 colchici 64 Acidum acetosum camphoratum ii. 63 Acidum acetosum distillatum 116 forte 118 benzoicum 120 citricum i. 350, ii. 122 aceticum 118 muriaticum 124 nitricum i. 184, 133 nitrosum 132 dilutum 133 oxy-muriaticum 1 7 succini i. 15 ;, ii. 100 sulphuricum i. 216 aromaticum ii 137 dilutum 136 vitriolicum i. 216 Aconitum napellus - 135 .TCrugo i. 252, 37© Page hippocastanum i. 336 iEther nitrosus ii. 145 sulphuricus i. 116, ii. 138 cum alcohole 143 alcohole aromaticus 144 ./Ethiops mineralis 244 Alcohol i. 110, ii. 100 ammoniatum 171 aromaticum 172 foetidum 173 dilutum 100 Allium sativum i. 325, 344 Aloe perfoliata 274 285 Althaea officinalis 381 Alumen 218 ustum ii. 175 Ammonia i. 252, 344, 357 Ammoniaretum cupri ii. 209 Amomum repens i. 209 zingiber 208 izedoaria 208 Ammoniacum 326 Amygdalus communis 385 Amylum 384 Amyris Gileadensis 329 Anchusa tinctoria 230 Anethum graveolens 210 foeniculum 210 Angelica archangelica i. 211 Angustura 197 Anisum 2L0 374 LATIN INDEX Page Anthemis nobilis i. 200, 255 pyrethrum 332 Antimonium 243, 314, 323 Antimonii oxidum ii. 194, 203 murias 202 tartris 204 sulphuretum praecipitatum 199 Aqua acetis ammonias i. 311 ii. 173 ammonia; i. 357j h\ 170 anethi 99 carui 99 calcis 180 carbonatis ammoniae i. 312, ii. 168 cinnamomi 98 citri aurantii 98 medicas 98 cupri ammoniati 210 distillata 97 fosniculi 99 lauri cassias 98 menthae piperita; 98 pulegii 1 9[) viridis 99 potassae 154 pulegii 99 rosae centifoliae 99 styptica 210 stillatitiae 95 super-carbonatis potassae i. 365, ii. 153 sodae i. 366, ii. 164 sulphureti kali ii. 161 ammonias 175 Arbutus uva ursi i. 231 Argentum nitratem 163 vivum 164 Argilla 218 Aristolochia serpentaria i. 195 Arnica montana i. 146 Arsenicum 180, 371 Arsenici oxidum praeparatum ii. 259 solutio 259 Artemisia absinthium i. 201 santonica 375 Page Arum maculatum 1. 333 Assa foetida 156, 284 Asarum Europaeum 256, 337 Astragalus tragacantha 380 Atropa belladona 134 Aurantium Hispalense 202 B Balsamum Canadense i. 303 Copaiba 303 Gileadense 329 Peruvianum 327 myroxyli Peruiferi 327 styracis benzoini 328 Toluifera; balsami 328 Tolutanum 328 Barytes 183 Belladona 134 Benzoinum 328 Bismuthum 182 Bistorta 230 Bitumen petroleum 155 Bolus armena 218 Borax 355 Byronia alba 273 Bubon galbanum 157 C Callicocca ipecacuanha 253 Cancrorum chelae 359 lapilli 359 Calx i. 183,219, 358, 367. ii. 180 Calomelas i. 277, 314, ii. 228 Calamina praeparata 254 Camphora i. 118, 316 Canella alba 204 Cantharis i. 305, 341 Capsicum annuum 206 Carbonas ammonias 312, ii. 167 calcis i. 220, 358 pr i paratus ii. 178 ferri praecipitatus ii. 212 pra- paratus 211 magnesias i. 359, ii. 182 potassae 150, 153 LATIN INDEX. 375 Page Carbonas potassa; purissimus ii. 152 sodas 161, 162 zinci prasparatus 254 Cordamomum minus i. 209 Carum carui 209 Caryophyllus aromaticus 2O6 Cascarilla 197 Cassia 204 fistula 266 senna 269 Castor fiber 153 Castoreum 153, 284 Cataplasma fermenti ii. 309 sinapeos 309 Catechu i. 232 Causticum commune 369 lunare 369, ii. 193 Centaurea benedicta i. 202 Cera 386 Ceratum ii. 286 carbonatis zinci impuri 296 cetacei 288 lapidis calaminaris 296 lyttae 2!J9 plumbi 296 resina; fiavae 288 saponis 300 simplex 287 Cerussa i. 223 acetata ii. 251 Chamasmelum i. 200, 255 Chelae cancrorum praeparatae ii. 178 Chironia centaurium i. 201 Cicuta i. 135 Cinchona Caribaea 195 officinalis 188 Cinnabaris factitia ii. 249 Cinnamomum i. 203 Citras ammonias 312 Citrus aurantium 202, 352 medica 203, 350 Cochlearia armoracia 333 Colehieum autumnale 301 Colocynthis . 273 Colomba 198 Page Confectio aromatica ii. 269 japonica 271 opiata 272 amygdala; 273 rutae 273 scammoniae 273 Conium maculatum i. 135 Conserva ii. 13 citri aurantii 13 rosae gallicae 13 caninae 13 Contrayerva i. 196 Convolvulus jalapa 271 scammonia 276 Copaifera officinalis 303 Coriandrum sativum 210 Cornu cervi 334 ustum ii. 9 Cortex Peruvianus i. 138 Cremor tartari 279, 293 Crocus antimonii ii. 201 sativus i. 158 Croton eleutheria 197 Creta praeparata ii. 178 Crystalli tartari i. 279, 293 Cubeba 208 Cucumis colocynthis 273 Cuminum cyminum 210 Cuprum i. 179, 22] ammoniacum ii. i'09 vitnolatum i. 3 69 Cusparia febrifuga 197 Cycas circinalis 383 D Daphne mezereum i. 318, 334 Datura stramonium 145 Decoctum althaea; officinalis ii. 39 aloes 44 anthemidis nobilis 40 chama-meli 40 cinchonas officinalis 40 commune 40 cydoniae 45 daphnes mezerei 41 dulcamara; 45 LATIN INDEX. 376 Page Decoctum digitalis ii, 47 geoffraeas inermis 42 guaiaci compositum 42 hellebori albi 47 hordei distichi 42 lichenis 45 * lignorum 42 malvae 46 papaveris 46 polygalae senegas 43 quercus 46 sarsaparillae 43 ulmi compositum 47 Digitalis purpurea i. 138, 297 324 Dolichos pruriens 374 Dorstenia contray erva 196 Dulcamara 301 E Elaterium i. 273 Electuarium aromaticum ii. 269 cassia? fistulas 270 sennae 270 catechu 271 lenitivum 270 opiatum 272 scammonii 273 thebaicum 272 Elixir paregoricum 76, 79 sacrum 77 Emplastrum adhassivum 303 ammoniaci 307 ammoniaci cum hydrargyro 307 aromaticum 309 assaLfoetidae 303 calefaciens 308 cantharidis 305 ceras 302 commune 302 cumini 307 gummosum 304 galbani 304 hydrargyri 304 lithargyri 303 meloes vesicatorit 305 Page Emplastrum meloes compositum ii. 306 opii 308 oxidi ferri rubri 303 plumbi semi vitrei 302 picis 308 resinosum 303 roborans 303 saponaceum 305 simplex 302 vesicatorium 305 Emulsio amygdalis communis 22 arabica 22 camphorata 22 Emulsiones ii. 21 Eugenia caryophyllata i. 206 Extracta ii. 83 Extractum anthemidis nobilis 85 aloes 87 absinthii 92 quercus 93 cascarillae 95 cassias sennas 86 catharticum 88 chamasmeli 85 cinchonas 88,93 colocynthidis compositum 88 convolvuli jalapi 94 corticis Peruviani 88 cum resina 93 genistas 92 gentianae luteae 85 glycyrrhizae 86 hellebori nigri 86 haematoxyli Campechensis 86 humuli 89 jalapas 93, 94 opii 90 papaveris somniferi 87 rhei 91 rutae graveolentis 87 sabinae 93 sarsaparillae 91 sennae 86 taraxaci 91 valeriani 92 LATIN INDEX 377 Page F Ferri limatura purificata ii. 211 oxidum 211, 214 carbonas 212 sulphas 213 murias 215, 217 tartarum 218 acetas 219 Ferrum i. 174, 220,285, 74 ammoniatum ii. 217 tartarisatum 218 Ferula assafostida i. 156, 284 Filix mas 376 Fraxinus ornus 265 G Galbanum i. 157 G alias 229 Gambogia 276 Gas acidum carbonicum ii. 335 hydrogenium 334 carbonatum 337 oxidum nitrosum 332 oxygenium 331 Genista i. 302 Gentiana lutea 200 Geoffrasa inermis 376 Glycyrrhiza glabra 382 Gratiola officinalis 302 Guaiacum officinale 316 Gummi Arabicum 380 astragali tragacanthas 380 mimosas niloticae 380 H Hamatoxylon Campechianum i. 231 Helleborus albus 337 niger 272, 286 Hepar sulphuris ii. 160 Heracleum gummiferum i. 326 Humulus lupulus 148 Hydrargyrus 164,285, 331 calcinatus ii. 247 cum crete 345 magnesia 245 muriatus corrosivus 225 Page Hydrargyrus mur. mitis ii. 228 praecipitatus ruber 240 albus 248 purificatus 222 sulphuratus niger 244 ruber 249 Hydrargyri acetas 223 murias i. 173, 370 ii.225 sub-murias ii: 228,233 sub-murias ammoniatum ii. 248 sub-nitras i. 370, ii. 240 oxymurias ii. 225 oxidum cinereum 2 '6 rubrum 246 Hydrargyri oxidum per acidum nitricum 240 sub-sulphas flavus 243 sulphuretum rubrum 2 43 nigrum 244 Hydro-sulphuretum ammonia; i. 253, ii 174 Hyoscyamus niger i. 133 Hyssopus officinalis 211 I Ichthyocolla i. **85 Infusa ii. 27 Infusum amarum 29 anthemidis 31 aurantii 32 columbae 32 caryopbyllorum 33 cascarillae 33 cuspariae 33 catechu 30 cinchonas officinalis 28 digitalis purpureas 29 gentianae luteas 29 japomcum 30 lini 33 rhei palmati 30 rosae Gallicae 30 sennae 34 tamarindi Indici cum senna 83 Vol. II. 49 LATIN INDEX. 378 Page infusum menthae compos, ii. 35 quassia? 34 simaroubae 34 tabaci 34 Valerianae 35 Ipecacuanha i.253, 323 Iris Florentina 336 J Jalap i. 271 Juniperis communis 302 sabina 287 K Kermes mineral ii. 200 Kino i. 233 L Lac ammoniaci ii. 23 amygdalae 22 assaefcetidae 23 Lactuca virosa i. 145, 301 Laudanum liquidum ii. 75 Lauro-cerasus i. 149 Laurus camphora 118 cassia 204 cinnamomum 203 sassafras 318 Lavandula spica 336 Lichen Islandicus 384 Lirnonum 350 Linimentum ammoniae ii. 11 >i aqua? anodynum 78 camphorae compositum 68 calcis 287 saponaceum 77 simplex 287 volatile 113 Linum usitatissimum i. i 81 Lithirgyrum 223 Liquor plumbi acetatis ii. 252 arsenicalis 259 aluminis 176 antimonii tartarizati 208 cupri ammoniati 210 ferri alkalini 221 hydrargyri oxymuriatis Lixivium causticum 154 Page Lytta vesicatoria i. 305, 341 M Macis i. 205 Magnesia i. 269, 359, ii. 182 Majorana i. 336 Malva sylvestris 382 Manna i. 265 Maranta arundinacea 383 Marrubium vulgare 202 Mastiche 235 Mel boracis ii. 56 colchici 57 despumatum 56 rosae 57 scillae 57 Melaleuca cajeputa i. 159 Melampodium 272 Meloe vesicatorius 305, 341 Mentha piperita 211 pulegium 211 sativa 211 viridis 211 Menyanthes trifoliata 202 Mercurius 164 Mezereum 318,334 Mimosa catechu 230 nilotica 380 Minium 223 Misturae ii. 23 Mistura ammoniaci 23 assafoetida? 23 cornu usti 24 ferri composita 25 guaiaci 26 camphorae 24 creta? 25 moschi 26 Momordica elaterium i. 273 Moschus 152 Mucilago amyli ii 36 gummi Arabici 36 tragacanthae 36 Murias ammonae i. 313 ammonia? et ferri ii. 217 antimonii i. 369 «• 202 baryta: ii. 176 hydrargyri i. 173,370 ii. 225 LATIN INDEX. 379 Page Murias sodas i. 280 Myristica moschata 205 Myroxolon peruiferum i. 327 Myrrha 326 Myrtus pimenta 208 N Nicotiana tabacum i. 143, 281 301, 324, 334, 337 Nitras argenti i. 369, ii. 193 potassae 294, 355 Nitrum i. 294 Nux moschata 205 vomica 148 O Oculi cancrorum prasparati ii. 178 Olea Europaea i. 375 distillata vel volatilia 41 ii. 105 fixa sive expressa 20 Oleum animale i. 154 anthemidis ii. 109 ammoniatum 113 amygdalae communis 20 cajeputae i. 159 carnphoratum ii. 114 cornu cervi 112 oethereum 144 lini cum calce 287 usitatissimi 21 olivarum i. 375 pini ii. 112 ricini i. 267, ii- 21 succini i. 154 ii 110 sulphuratum ii. 114 f erebinthinas i. 304 rectilicatum ii 112 volatile anisi 109 carui 109 juniperi communis 108 sabinae 108 lauri sassafras 108 lavandulae spicae 108 volatile melaleucae leucadendri i. 159 menthae piperitae ii. 108 Page Oleum volatile menthae viridis ii. 109 myrti pimentae 109 origani 109 pimpinellae anisi 109 pulegii 110 rorismarini 109 rutae 110 sabinae 108 sassafras 108 Opium i. 121, 315 purificatum ii. 95 Opobalsamum i. 329 Origanum majorana 336 Orchis mascula 383 Oxidum antimonii cum phosphate calcis ii 196 antimonii cum sulphure per nitratem potassae 201 antimonii cum sulphure vitrificatum 194 antimonii vitrificatum cum cera 195 arsenici i. 371 ii. 259 ferri purificatum ii. 211 rubrum 214 hydrargyri cinereum 239 hydrargyri rubrum per acidum nitricum i. 370 ii. 240 plumbi semivitreum i. 223 zinci vi. 255 impurum prae paratum 254 Oxymel 57 colchici 57 scilla; 57 aeruginis 58 Oxymurias potassae i. 185 ii. 127 P Papaver somniferum i. 121 Petroleum Barbadense 155 Phosphas hydrargyri IT3 sodas i. 280 ii. 165 Pilulae aloes 2^5 LATIN INDEX. 380 Page Pilula aloes cum assafcetida ii. 276 colocynthide 276 myrrha 276 zingibere 275 ammoniareti cupri 277 assafoetidae composita; 27T galbani compositae 277 hydrargyri 278 myrrha; composita; 278 opiitas 279 rhei compositae 280 scilla 281 thebaicae 279 saponis cum opio 280 e sty race 280 cambogia? 282 ferri cum myrrha 282 hydrargyri sub-muriatis 282 Pimento i. 208 Pimpinella anisum 210 Pinus apies 343 balsamea 303 larix 304 Piper cubeba 208 indicum 208 longum 207 nigrum 207 Pistacia lentiscus 235 terebinthinum 805 Pix Burgundica 343 Plumbum 222 Plumbi acetas ii. 251 Poly gala senega i. 325 Polygonum bistorta 230 Poly podium filix mas i.376 Potassa i 292, 356, 365, 368 ii. 156 cum calce i. 368, ii 157 Potio carbonatis calcis ii. 179 Prunus lauro-cerasus i. 149 Pterocarpus draco 235 Pulegium 211 Pulvis aloes cum canella ii. 267 guaiaco 2u6 antimonialis 169 aromaticus 262 Page Pulvis asari compositus ii 262 carbonatis calcis compositus 262 cret.iceus 263 cretae compositus 263 cum opio 2b3 contrayervae compositus 267 cornu usti cum opio 265 doveri i. 315, ii. 264 ipecacuanha; et opii i. 315 ii. 2 64 jalapae compositus 263 kino compositus 267 opiatus 264 scammonii compositus 265 sennas compositus 268 stypticus 266 sulphatis aluminae compositus 266 tragacanthae compositus 268 Pyrethrum i. 332 Quassia excelsa i. 200 simarouba 199 Quercus robur 2 9 cerris 229 marinus ii. 10 R Raphanus rusticanus i. 333 Resina alba 304 copaiferae oflicinalis t>02 flava 304 laricis 304 Rhabarbarum 270 Rhamnus catharticus 274 Rheum palmatum 270 Rhododendrum crysanthum 147 Rhus toxicodendron 147 Ricinus communis 267 Rob sambuci ii. 19 Rosagallica i. 231 Rosmarinus officinalis 336 Rubia tinctorum 286 Rubigo ferri praeparata ii. 211 LATIN TNDEX. 381 Page Ruta graveolens i. 286 S Sabina i. 287, 371 Saccharum saturni ii. 251 Sagapenum i. J57 Sago 383 Salina ii. 115 Sal ammoniacus i. 313 cornu cervi i. 155, ii. 169 diureticus i. 293, ii. 157 glauberi i. 278, ii. 166 marinus i. 280 martis i. 175, ii. 213 polychrestus ii. 159 rupellensis i. 280, ii. 164 sOdae 162 succini 110 tartari 152 Salop i. 383 Salvia officinalis 319 Sanguis draconis 235 Santonicum 375 Sapo albus 366 Sarsaparilla 382 Sassafras 318 Scammonium 276 Scilla maritima 255, 296, 324 exsiccata ii. 5 Seneka i. 325 Senna 269 Serpentaria Virginiana 195 Sevum ceti 386 Simarouba 199 Sinapis alba 256, 286, 343 Smilax sasaparilla 382 Soda 357, 366 Solarium dulcamara 301 Solutio acetitis zinci ii. 257 muriatis baryta; 178 muriatis calcis 181 sulphatis cupri composita 2 i 0 sulphatis zinci 257 Spartium scoparium i. 302 Spermaceti 386 Spigelia Marilandica 376 Spiritus stillatitii ii. 100 Page Spiritus aetheris nitrosi i. 296 ii. 148 aetheris vitriolici 144 ammonias 171 aromaticus 172 foetid us 173 succinatus 173 anisi 101 armoracia? compositus 102 camphoratus 68 cari carui 101 cinnamomi 101 juniperi compositus 102 lavandulae spicae 103 composita 103 menthae 101 mindeieri i. 311, ii. 173 myristicae moschatae ii. 101 myrti pimentae iOI nitri dulcis i. 296, ii. 148 pimentae 101 pulegii ii. 101 rorismarini officinalis 03 vinosus rectificatus 104 vinosus camphoratus 68 Spongia usta 9 Squama? ferri purificatae 211 Stalagmitis cambogioides i. 270 377 Stannum 675 Stanni pulvi6 ii. 258 Stramonium i. 145 Strychnos nux vomica 148 Styrax benzoin 328 officinale 329, ii. 7 Sub-acetis cupri i. 370 Sub-boras sodae 355 Succi ii. 14 Succi spissati 15 Succus cochleariae compositus 15 Succus spissatus aconiti napelli 17 atropa? belladona; U 382 LATIN INDEX. 1 Page Succus spissatus conii maculati ii. 17 hyoscyami nigri 18 lactucae virosae 18 momordicae elaterii 19 sambuci nigri 19 Sulphas aluminae i. 218 alumina; exsiccatus • ii. 175 cupri i. 179, 252, 369 ferri 175, ii. 213 exsiccatus 214 magnesias i. 277 potassae i. 278, ii. 158 potassae cum sulphure 159 sodas i. 278, ii. 166 Sulphas zinci i. 178, ii. 256 Sulphur i. 268, 315 antimonii praecipitatum ii. 199 praecipitatum 11 sublimatum lotum 11 Sulphuretum antimonii i. 242 antimonii praeparatum ii. 194 antimonii praecipitatum 199 hydrargyri nigrum 244 hydrargyri rubrum 249 potassae 160 Super-sulphas aluminae et potassa; i. 218, 368 Super-tartris potassae 279, 293 354 Swietenia febrifuga 198 mahagoni 198 Syrupus acidi acetosi ii 49 allii 55 althaea; officinalis 49 amomi zingiberis 49 citri aurantii 50 Pago Syrupus citri medici ii. 50 colchici autumnalis 50 communis 48 croci 54 dianthi caryophyll. 51 mori 54 opii 55 papaveris somniferi 51 rhamni cathartici 52 rhoedos 54 rosae gallicae 52 centifoliae 52 scillae maritimae 53 sennae 55 simplex 48 limonis succi 50 toluiferae balsami 53 violae odoratae 53 zingiberis 49 T Tamarindus Indica i. 266, 353 Tanacetum vulgare 376 Tartari crystalli 279, 293, 354 Tartarus emeticus ii. 204 Tartarum solubile 160 vitriolatum 158 Tartris antimonii 204 potassae i. 279, ii. 160 et soda; i. 280 ii. 164 Terebinthina Veneta i. 281,304 Testae praeparatae ii. 10 Tinctura aloes aetherea 66 aloes socotorinae 66 cum myrrha 67 aloes composita 67 amomi repentis 67 angusturae 82 aristolochiae serpentariae 67 aromatica 70 assasfoetidas 71 aurantii 79 balsami Tolutani 78 benzoin composita 68 c amphorae fe»8 LATIN INDEX. 383 Page Tinctura camphorae composita ii. 79 cantharidum 74 cardamomi composita 80 capsici 80 castorei 69 cascarillae 80 castorei composita 69 catechu 74 cinchonas composita 80 officinalis 69 cinnamomi 74 composita 70 colombae 70 convolvulijalapae 70 croci 71 digitalis purpureas 71 ferri acetatis 220 ferri ammoniata 217 ferri muriati 215 galbani 83 gentianas composita 72 guaiaci 72 guaiaci ammoniata 72 hellebori nigri 73 humuli 81 hyoscyami nigri 73 jalapas 70 japonica 74 kino 73 lauri cinnamomi 74 meloes vesicatorii 74 mimosas catechu 74 moschi 83 myrrhae 75 opii 75 opii ammoniata 76 opii carnphorata 79 quassiae 83 rhei palmati 76 rhei et aloes 77 rhei et gentianas 77 rhei composita 81 sacra 59 saponis 77 saponis cum opio 78 scillae 81 Page Tinctura sennas ii. "'8 serpentarias 67 thebaica 75 Toluiferae balsami 78 valerianas 82 Valeriana? ammoniata 82 veratri albi 79 zingiberis 82 zinci acetatis 258 Toluifera balsamum i. 328 Tormentilla erecta 230 Tragacantha gummi 380 Triticum hybernum 384 Trochisci carbonatis calcis ii. 283 cretae 283 glycyrrhiza; 284 cum opio 284 gummosi 285 nitratis potassae 285 Turpethum minerale 243 Tutia praeparata 254 U Unguentum acetis plumbi 295 acidi nitrosi 295 cantharidis 289 cerae 288 cerussae acetates 295 cceruleum 290 elemi compositum 298 episp;;sticum fortius 289 mitius 289 hellebori albi 299 hydrargyri i. 169 ii. 290 prascipitati albi ii. 299 nitrati 294 infusi meloes vesicatorii 289 oxidi hydrargyri cinerei 29" 384 LATIN INDEX. Page Unguentum oxidi hydrargyri rubri ii. 293 oxidi plumbi albi 295 oxidi zinci 297 oxidi zinci impuri 297 picis 297 pi peris nigri 301 pulveris meloes vesicatorii 289 resina; rlavae 288 resinosum 288 sabinae 300 sambuci 299 saturninum 295 simplex 287 spermatis ceti 288 sub-acetitis cupri 290 sulphuris 298 compositum 298 tutiae 297 veratri 299 Uva ursa i. 231 V Valeriana officinalis 158 Page Veratrum album i. 337 Vina ii. 58 Vinum aloes socotorinae 59 amarum 59 antimoniale ii. 208 antimonii tartarisati 208 ferri 61 gentianae compositum 5S ipecacuanha 60 nicotianae tabaci 60 opii 61 rhei palmati I 0 tartritis antimonii 208 Vitriolum album 256 coeruleum i. 179,252 viride i. 175, ii- 213 Vitrum antimonii ii. 194 antimonii ceratum 195 Z Zedoaria i. 208 Zincum 177, 220, 252 Zinci carbonas ii. * 54 oxidum 255. sulphas 256 aretas 257 Zingiber L 208 FINIS.