Wm NATIONAL LIBRARY OF MEDICINE Bethesda, Maryland a k$\ rfnaA r-t/*w< *-v f- i ■-V.M:-' / /■ / * i i V !$.....3 r^T u. Engraved for J.HIitfnphreyf CHEMICAL POCKET-BOOK; OR MEMORANDA CHE MIC A: A R R A N;G Z r> IN A COMPENDIUM OF CHEMISTRY: WITH TABLES OF ATTRACTIONS, &c. CALCULATED A3 WELL FOR THE OCCASIONAL REFERENCE OF THE PROFESSIONAL STUDENT, AS TO SUPPLY OTHERS WITH A GENERAL KNQWLEDGEQE CHEMISTRY. BY JAMES PARKINSON. WITH THE LATENT DISCOVERIES. **0M THE LONDON SECOND EDITION OF l8oi. To which is noio addtd Containing THE PRINCIPAL OBJECTIONS TO THE ANTIPHLOGISTIC SYSTEM OF CHEMISTRY. BY JAMES JVOODIIOUSE, M. D. Profefor of Cbemiftry in the Umverfty of Pennfyl-vania, &e. EMBELLISHED WITH COPPERPLATES. ^Ma&elpgta: PRINTED AND SOLD BY JAMES HUMPHREYS, At the N.W. Corner of Walnut and Dock-ftreet. 1802. / DESCRIPTION OF THE FRONTISPIECE. IN the upper part of the plate fs reprefented The ECONOMICAL LABORATORY of GUTTOH, which may be feen to confift of an Argand's lamp, and a frame work with a ring, in which a retort is fufpend- ed ever the lamp. The retort is connected with its re- ceiver, in which is received whatever on pafling over will condenfe into a fluid ftate. From the receiver pro- ceeds a tube, through which the feveral gafeous matters which are extricated pafs into their proper recipient. To prevent the efcape of the gas, this tube pafling through, nvater; or, if the gas is fufceptible of abforption by wa- ter, through qjjicksu,ver, which is contained in the. pneumatic trough, opens underneath the receiver, which is a glafs veflel inferted in the fluid contained in the trough. To prevent any accident arifing from the difference between the elafticity of the contents of the veflels and that of the external air, the reverfed fyphon or tube offafety of WELTER is employed, which adis in this manner. Into the upper bell-fhaped veflel, which is nearly of the fame magnitude as the bulb at the lower end of the tube, a quantity of fuitable fluid, fomewhat lefs than the contents of that veflel, is put. Then, if the elafticity of the contents of the veflels be lefs than that of the external air, the fluid will defcend into the bulb, and atmofpheric air will follow, and pafs through the fluid into the veflels; but, on the contrary, if the elafticity of the contents be greater, the fluid will be either fuflained in the tube, or driven into the bell-fliaped veflel ; and if the force be ftrong enough, the gafeons matter will pafs through the fluid, and in part efcape. IV Thus is formed the pneumato-chemical appa- ratus. By reverfing the frame work, removing that piece to which the neck of the retort was fufpended, and fhortening the glafs chimney of the lamp, the apparatus is rendered fit to perform evaporation or faline fufion, a capsule of glafs, platina, &c. being placed on the ring ihftead of the retort; or, a triangle of iron being placed on the ring, a fmall crucible may be fubfti- tuted. A fuller defcription of this apparatus is to be found in Mr. Nicholson's excellent Journal. The Tablet in the lower compartment of the plate ex- hibits the CHARACTERS employed by Hafifenfratz. and Jdet, for the fyrnbolical expreilion of the fubjccts of chemiftry, and of their affinities and compofition. The firft character in the firft column, denotes light; the one beneath it caloric, to which fucceed oxy- gen and nitrogen. ThefeYour are fimple fubji'an- tes, which may exift in a gafeous fate at the ordinary fate of tfo aimofpbere. The next denotes fixed al- kali, which, by the central infertion of the initial let- ter, ferves to denote either poi-afh or foda. The laft character in this column is that of simple earths, which by the initial letter is made to denote lime, fili- ta, or any other fmple earth. The four firll characters in the fecond column denote fmple combuftible fubftances, commonly called inflamma- ble, in this order, sulphur, hydrogen, carbon, phosphorus. The next character is a circle denoting metals, a point in the centre denoting gold, and the initial letter placed in the fame manner diftinguifti- ing all the others. The next character, a fquare, de- notes radical acidifiable compounds, wohofe bafes are but little known, fuch as the muriatic, boracic, &c. the particular radical being marked by defcriptive let- ters in the centre. The firft character of the third column, a lozenge, denotes certain compound fubftances not having acidifiable bafes, nor having been yet compounded by fynthefis ; thefe are ether, alcohol, fixed oil, volatile oil, bitumen, mucus, and are alfo denoted by their V initial letters. To denote the addition of caloric, in fuch a portion, to any fubftanceas gives :.t the ftate of flu- idity, the character for that fubftancc is affixed to the bottom of the perpendicular line which ftands for calo- ric ; and its gaseous ftate is implied by its being af- fixed to the upper part of the perpendicular line. The presence of. oxygen is denoted by the addition of the horizontal line, which is the character denoting it ; if this be feparated by a fmall break, and placed lower thaji the ether charailer, a super-oxyg en ation a implied; and the higher it is placed the lefs the degree of fuppofed acidity. To illuftrate this, the fecond cha- racter is that of water in its fimpleft ftate (ice) being made by joining the characters of oxygen and hydro- gen ; it is followed by that of fluid water, and of water in ftate of gas, by the proper difpofition of the fymbol reprefenting caloric. The fifth in this column is the character marking oxy-nitric acid, and is follow- ed by nitric acid. The firft in the fourth column is that of nitrous acid, followed by nitrous acid gas, nitrous oxide gas, and oxidule or oxide of nitrogen gas. In this manner is defignated all the other com- pounds of oxygen and caloric with different bodies. Thus, for farther illuftration of this point, the fifth cha- racter denotes concrete arfenic acid, and the fixth, ox- ide of arfenic. The firft. character of the fifth column is that of am- monia, formed by Hydrogen and Nitrogen; the fecond is that of sulphurf.ts ; the third, ofpHOSPHURETs; the fourth, of carburets; the fifth, of amalgams; and the fixth, of alloys. The firft character of the fixth column is that of ace- tates, this character being formed by the union of that of acetic acid and earth, denotes an acetate with an earthly bafe: this is followed by acetites, bom- biates, carbonates, benzoates, and BORATES. The feventh column contains, camphorates, ci- trates, fluates, formiates, lactates and gallates, in the order here mentioned, A 2 VI The eighth column contains, malates, muri- ates, OXY-MURIATES, NITRATES, NITRITES, and OXALATES. The ninth contains, acidulous oxalates, phos- phates, PHOSPHITES, PRUSSIATES, SULPHATES and sulphites. The tenth contains, acidulous sulphates, sul- phates WITH EXCESS OF BASE, SUCCINATES, AR- SENIATES, ACIDULOUS ARSENIATES, ARSENIATES WITH EXCESS OF BASE. The characters for the remaining compounds of alka- line, earthy, or metallic bafes, with the tart a Rous, MOLYBDIC.TUNCSTIC, CHROMIC, SUBERIC, ZOO- NIC,PYROTARTARIC,PYROMUCIC,PYROLIGNIC, saccholactic, and sebacic acids, may be ea- fily inferred from an attentive confideration of the for- mation of the characters already described, *\ PREFACE. THE following assemblage of chemical facts was formed, with the hope of rendering it an a- greeable pocket companion for the lovers of Che- mistry in general; and more particularly so for those who may be just engaging in the study of this most useful and interesting science. To the latter the Author hoped it might be more particu- larly benefcial: furnishing, like a bird's eye view to a traveller, a general view of the relation and connection of the several parts of that region, which is soon to become the object of a nearer and closer investigation. It is hardly necessary to acknowledge the Au- thor's obligations to the various labours of Berg- man, Fourcroy, Lavoisier, Chaptal, Kir- wan, Hatchett, Pearson, Babington, Hie. as they must appear on the face of the work. Like the bee, he has roved freely, in search of vm materials; and shall be highly gratified if it ap- pear that he has even faintly imitated its skill in selection and arrangement. May this little Compendium lead fresh admi- rers into the delightful walks which are to be found in this department of science, where wide scenes of interest and amusement are constantly opening upon the mind. May it point out the indispensa- ble connection between Chemistry and most other sciences; and the vast advantages a knowledge of its principles may yield to those who are engaged in the most useful and profitable arts; and there- by induce those who are not of the medical pro- fession, to seize the opportunity of obtaining ful- ler information, by the pleasing and expeditious mode of Public Lectures^ CONTENTS. Page CHEMISTRY, definition of 13 Actra&ion of Aggregation . ib. Compofuion ib. Elective Attraction ... 14 EARTHS......15 Lima.......ib. Magnefia......16 Alumine......ib. Silica.......ib. Baryt.......ib. Strontia .... . . 17 Jargonia...... ib. Glucine . ..... ib. Aguftine......18 Opinions refpeiling by Girtan- ner, Guyton, &c. . . i;alcr.c ....... Calorimeters, Pyrometers, Sec. Opinions of Rumford, Gren, Beddoes, Davy, &c. . . Light ...... . Opinions of Pearfon, Hum- boldt, Wedgwood, &c. . 22 Oxygen......23 Oxidation......ib. Oxygen Gas.....ib. Combuftionlnnammation&c. 24 Hydrogen ...... 25 Gas.....ib. Water....... ib. Watery vapours Ice Dew &c. 26 Mineral Waters . . . . ib. Nitrogen......27 ib. ib. 28 ib. -Gas..... -Nitn'c Acid . . -Nitrous Acid -Nitrous Gas . . -Gafeous Oxide of Nitrogen ..... ib. Mr. Davy • Opinions of .Page tanner -Mayer, Gir- -Berthollet, Mitchill, &c. ———Atmofpheric Air . -----------'.—Eudiometer -----------—Barometer 28 29 30 ib. 3* 3a -Hygrometer ib. Making -Alkalies —----Ammonia _-----Pot-Afli . Soda . . —Glafs b. ib. 31 ib. ib. Silh -Liquor- kabeji <......34 -Neutral Salts ib. -Nitrates . . . ib. -Nitrate of Pot-Aih ib. -----Sal Prune! 35 -----Sal Polythreft ib. -----Fixed Nitre ib. -----Glauber s Al- ......ib. ib. -C'tyffus of Nitre -Acidulous Ni- trate of Pot-Aih . . . . ■ Gunpow- ib. -Nitrate of Soda --- Cubic ib. 36 Nitre......«b. _______—Nitrate of Am- moniac ...... jb. ■Time ib. —Bald- win's PHOSPHOaVS iJfe X Page 1 ' ■ Barytes . . _ . 37 ■ ----Magnefia, Alu- mine, and Strontian . . ib. ■r—Nitrites . . . ib. Sulphur.......ib. ————Sulphuret of Pot-aih, or Li-ver of Sulphur . . 38 ———Milk of Sulphur . . ib. Sulphurated hy- drogen gas . . . . ib. Sulphuret of Amonia ib. - Sulphuret of Lime . 39 ' Cauton's Phof- phorus.......ib. ———.Sulphuret of Barytes ib. Bononian Phofcihorus ib. Sulphuret of Magnefia ib. ■ Fulmina ting Poivder....... ib. Sulphuric Acid . . ib. » Sulphurous Acid . . 40 ■ ■ Gas . . ib. ----■—Sulphate of Pot-Aih ib. ■-------- Acidulous 41 — —*----------Soda . . ib. Acidulous.ib. ■ ' ---------Ammonia ib. ■ ---------Lime . . ib. ■---------------Magntfia . 42 ---------———Alumine . ib. Pyro- PHORl......43 . . Strontian . ib. Ziixonia . ib. Barytes . . ib. ... 1 Sulphites . . . . 44 Carbon ....... ib. Diamond . . . . ib. Charcoal . . . . 45 Carbonic Acid-Gas . 46 Carbonated Hydrogen Gas.......47 .______Carbonate of Pot-Aih ib. ___---- Soda ... 48 ._______________Ammoniac ib. ______ Lime . . ib. ______________-.....Aci- dulous......49 T»-"-y»»« . ib. Page Magnefia . 49 Alumine • ib. S tronti an, Zirconia. &c.....ib.. Muriatic Acid .... 50 -------------Gas . . . ib. Oxygenated .51 ---------.—-Mu. of Pot-aih 52 Soda . ib. Ammo- nia.......ib. Lime 53 ----------------Phof- phorus of Homberg . . ib.- . ■ ■ Mag- nefia.......ib. Barytes, Alumine, &c.....54 Qxymuriate of Pot-aih......ib. ------------Effefts with Phofohorus Gunpowd. &c. 55 ------'.-------------Soda . ib. Am- monia......lbv. ■ 1 .Nitro-Muri- atic Acid ..... ib. Acid of Borax .... 56 Borate of Soda ib* -------------------Pot-aih, Ammonia, &c. ... 57 Fluoric Acid.....ib. . ----Fluate of Pot-afh, Soda, &c......58 Metallic Substances 59 Ores........ib. Allaying . . . , . . ib. Platina.......61 Gold.......63 ----Gilding.....64 Silver.......65 ——Parting .... ib. Fulminating Silver 66 Quickfilver......67 Fulminating Q^Silver 69 Cooper.......71 Ir°n........73 ----Caft or Crude ... 74 ----Forged or Bar . .. . 75 XI Page . . ..Red Short'and Cold Short 75 ■Carburet of Iron . . ib. -----Anthracolite.....77 i----Plumbago . . . . ib. Lead.......82 ----Refining ... 84 Tin........85 Pewter, Tuttenag, &c. . . 88 Enamelling . . . . ib. Zinc.......89 Antimony......91 Bifmuth......94 Sympathetic Inks ... 95 Cobalt.......ib. Blues.......97 Nickel.......98 Manganefe...... ib. Uranite......101 Tellurite......ib. Titanite......102 Chrome...... 103 Arfenic......104 Molybdenite.....106 Tungftenite.....108 EleEiricity Galvanic . . • 109 Bitumin. Substances iio Petrol, Mineral Tar, Afphal- tum, &c......ib. Amber ..... .113 ■ Acid of .... ib. Succinates ... ib. Stones......114 Volcanic Productions . .119 Geological Remarks, by Mr. Kirwan .... 12s Primeval State of the Earth, &c........ 121 Vegetable substances 124 ■ Sap.....125 ■ Mucilage . . . . ib. Gum.....126 . Oils.....ib. 1. Fixed ... ib. -----------Volatik ... 128 ■ Camphor ... ib. ———Refins .... 12,9 ———Gum-Refins . • ib. Caoutchouc . . . ib. ------Balfams . . . . 130 Page -Faecula . . . .130 -Vegetable ... ib. -Gluten .... ib. -Sugar . . . . 131 -Albumen, Vegetable 132 -Vegetable Acids ---------Citric . ■ Malic . ---------Gallic . --------------Ink ib. ib. 134 . x35 Tannin ib. -Benzoic . 136 -Tartarou* 137 -Oxalic . 138 -Camphoric 139 -Suberic . 140 -Pyrotartaro. ib. -Mucous . ib. -Pyromucous ib. -Lignous . 14! —Pyrolignous ib. —Acetous . ib. -Fermentat. 141 -Alcohol -Ether -Alkalies , • • • -Colouring Principle -Pollen .... -Wax . . • -Honey . • < -Ligneous Part —Aroma . . -Charcoal . . . . ib 142 H3 146 149 ib. 150 ib. ib. Refolution of Vegetables by Combuft. Putrefatt. &c. Agriculture . 152 154 iS5 Animal Substances -----Blood . . . ■ ■Opinirmg of Gren, Hatchett, &c. • 156 ------Gaftric Juice . . 157 ------Pancreatic Juice . ib. ------Milk.....jb- ___________Lattic Acid . ib. _______.Sugar of . • . 158 .________—Sac-Lactic Acid ib. __________-Cheefe . . . ib. -. ----Butter . - • 159 XII Page ' " Sebacic Acid . 159 ■ lOpinions of Gren, Beddoes, Alyon, &c. 160 Spermaceti ... . ib. -----Bile.....161 -----Soft and White Parts ib. 162 164 ib. of Animals . Gelatin -Fleihy Parts . Albumen -Obfervations of Ba- con, Fourcroy, Crawford, G ibbes, Vauquelin, Jame- fon, &c......166 ■ 1 Urine .... 167 -Phosphorus of Urine ..... . 169 ■ Opinions of Gottling, Van Mons, Brugnatelli^ Girtanner, Gren, &e. . 170 ■ Phofphoric Acid . ib. -Pbofphates 171 -----Calculus of the Blad- der . . ..... 172 11 Uric Acid . ib. Opinions of. Scheele, Pearfon, Fourcroy, &c. . 174 ■■ ■■ Prufiic Acid . . 175 Bombic Acid . . .176 1 1 -Hartfhorn . . . . ib. -Bones -Phofpho Page 176 177 ib. 178 179 181 ib. ib. 182 Horus of . -Enamel of Teeth . -Shells, Cuttle Bo-e, -Cartilage and Horns -Zoophytes ... -Synovia .... -Tears..... -Mucus of the Nofe -Saliva . . . . . ib. -Pus.....ib. -Semen .... ib, -Sweat .... ib, -Liquor of the Amnios ib. 183 ib. 184 185 ib. ib. ib. ib. ib>. ib, 1? ——.Zoonic Acid Formic Acid . -------Eggs..... Hairs, &c. . . , Feathers . . -------Silk . . . . . .Concretions, boney -Cantharides .. . .Millepedes . . . 1 Cochineal . . . ii-n 1 Ambergris . . . ...Animal Putrefaction Table of Affinities . . . 1 Remarks. on . . Tables by Mr. Kirwan . 183 CHEMISTRY. CHEMISTRY is the Science which difcovers the con- ftituent principles of bodies, the refults of their vari- ous combinations, and the laws by which thofe combina- tions are affefted. Chemical inquiries are profecuted by certain operations or procefles ; which are performed either by Analysis, or Decompofithn, or by Synthesis, or Compofition. Thefe operations depend on the affinities, or powers of attraction, which act on bodies, and on the ele- mentary parts of bodies. The Attraction op Aggregation is that by which the homogeneous particles of bodies are united. The Attraction, or Affinity of Composition, is that by which the heterogeneous particles of bodies are united. The general principles, cr laws by which this power afts, are— i. It takes place between the confntuent parts of bodies of different natures. Thus acids combine with alkalies, alka- lies with fulphur, metals with acids, &c. 2. It ails in the inverfe ratio of the affinity of aggregation. For as it appears to aft on the infinitely fmall particles of bodies, its operation muft be impeded by that force of ag- gregation which allows but few of thefe ultimate molecules to be expofed to its influence. Thus metals are not afted on by fulphur or faline fubftances, whilft each retains a folid form; but when by a ftate of fluidity, a more extend- ed application of the particles of one of the bodies takes place, the capacity of aftion is thereby increafed, and a combination enfues, which, in the cafe of a folid and a fluid body, is termed folution ; and the fluid body has been termed a fol'vent, and has been fuppofed to aft with a fupe- rior degree of force than the folid aggregate. This, how- ever, is not the cafe, fince the aftion is equal on both fides ; and the new combination is the confequence of the affinity of compofition between the two fubftances exceeding the affinity of aggregation. B 14 3. Bodies, immediately on being united by it,fuffer a change tf temperature. This depends on the change which takes place with refpeft to the degree of attraftion for the matter of heat. 4. The Compound poffeffes properties differing from thofe which were before poJJ'effed by the bodies of which it is com- fofed. This difference may exift not only in the tafte, but aho in the confidence, form, fmell, colour, fufibility, &c. 5. All bodies have their own peculiar affinities with other bodies. Thus fome bodies refufe to unite, whilft others form an almoft infeparahle union. By obtaining a knowledge of the powers of thefe refpec- tive affinities, the ref'ult of different combinations maybe previoufly ascertained. Tfiis knowledge is obtained by meafuring the difficulty with which combinations are de- irroyed, on the application of other fubftances. Thus an acid may be preferred in union with a metal, by a certain degree of elective attraction ; but on an alkali be- ing prefented to this compound, a decompofition takes place, the alkali immediately unites with the acid, forming a new combination, and manifefting a fuperior degree 0/ attraction, the metal being at the fame time feparated in a precipitate. This is termed a cafe of decompofition by sjn- cle elective attraction, oy Jimp le affinity, in which one of two principles is difplaced by a third. But when two bodies, each confifting of two principles, fuffer decompofition, by a reciprocal exchange and union of their elements, by which two new compound bodies are produced, this change is faid to be effefted by double elective attraction, or double Affinity. Mr. Kir- wan employs the term, ^uiefcent Affinity, to mark that, by virtue of which, the principles of each compound adhere to each other ; and Diuellent Affinity, to diftinguifh that by which the principles of one bady unite, and change order with thofe of the other. Confidering the degrees of 'affinity to be precifely as the points of fauiration, he therefore marks the degree of af- finity of any body with an acid, by the quantity of that bo- dy which may Be diifoked in 100 parts of the acid. Thus fuppoling 96 grains of lime to be required to fatuiate 100 grains of nitric acid, he takes 96 for the numerical ex- prefiion of its degree of affinity with that acid. The af- finity of pot-aih with the fame acid he thus finds to be 215, and therefore fays, the affinities of lime and of pot-afh to nitric acid is as 96:215; and that, therefore it may be inferred that a combination of nitric acid and lime muft be decompofed by pot-afh. 15 Thefe numbers however are not to be confidered as ex- preffive of the exail forces of attractions, but fufficiently fo to enable us to foretel decompoiitions and compofitions. The real nature of what are termed reciprocal attractions, cannot be underftood, unlefs the agency of certain interpo- fing attraftions be alfo confidered, fuch as thofe of caloric, fght, and the furrounding air^ with the difference of cohe- fion, and of gravitation in the particles of the compounds, as well as in the particles of the menftrua and bafes, &c. Thefe apparent reciprocal affinities being generally the re- fult of certain combinations not hitherto fufficiently ex- amined. OF EARTHS. EARTH is an inodorous, dry, brittle, uninflammable, naturally white, and generally taftelefs fubftance ; of very fparing folubility in water, but foluble in one or other of the acids : from which folution no precipitate is produced by piufliate of pot-afh, or of lime. Sp. gr. to water no$ exceeding 5 to 1. There appear to be nine different earths, which may be confidered as fimple fubftances. 1. Lime, when perfeftly pure, is termed $UI€K- LIME, or pure calcareous earth - To obtain it in that ftate, after clearing it as much as poflible from extraneous matters, it muft be long expofed to a ftrong heat. It is then white, moderately hard and brittle, and its fpecific gravity 2,3. It yields a hot burning tafte, changes violets green, and cor- rodes animal and vegetable fubftances. It heats and burfts by the application of water, 100 grains abforbing 28,7 of water, and becoming SLAKED LIME, during which change a degree of phofphortfeence may be difcovered in the dark. It requires nearly 700 times its weight of water to hold it in folution; this folution, which is called LIME V/ATER, has rather an arid tafte; on expofure to the air the lime feparates from it. L;me combines with all acids, particularly with the nitric and muriatic: thefe folmions chryftallize difficultly and yield the lime to the fulphuric. Lime alone is infufible, it may however be fufed when joined with filica and clay. Mixed with borate or pbof- phate of foda, it is fufed without effervefcence. It has been fuppofed to be entirely of animal origin ; but this is doubtful where it exifts as primitive lime-ftone, or in granite. 16 a. Magnesia has not been met with native in an uncom- bined ftate. When pure it is very light and white, and requires 7,900 times its weight of water to hold it in folu- tion. Sp. gr. about 2,3. It combines with all the acids, the fulphuric taking it from the nitric or muriatic without forming a precipitate. It is as infufible as lime, and like it is fufed when mixed with the phofphate, or borate of foda, and without effer- vefcence. 3. Alumine, or EARTH OF ALUM, is tfie true argil- laceous part of common clay. It is never found pure, in a native ftate. When pure it is white, fmooth, and of an unftuous feel, adherent to the tongue, diffufible in water, and not more folublethan magnefia. Sp. gr. 2,00. When heated it diminifhes in bulk, and may be fo hardened by fire as to give fparks with fteel. It combines with moft acids, though with difficulty, uniting beft during precipitation. With the fulphuric it forms alum, but with the nitric and muriatic it chrvftallizes difficultly. J It is fufible alone, only by the flame of oxygen gas ; but with phofphate or borate of foda, it may be fufed with nearly the fame degree of facility as lime and magnefia. 4. Silica is the earth which chiefly forms flint, reck cryftal, and many of the gems. It is of a rough and harfh f-'d, and appears to be foluble in. water itfelf. Fifty grains of colourlefs fluid, contained in the cavities in bafalt, have been found to held a grain of filiceous earth in folution. It is afted on by no other known acid, but the fluoric, and yet an alkaline folution of this earth admits of fuperfaturation with an acid without any precipitation. It is infufible alone, and is but little afted on by phofphate of foda, and but little more by borate of foda. Fixed alka- lies are the effcftual folvents of this earth, forming with it glafs. Effcrvefcence takes place in this cafe, but not with the borate of foda. The fixed alkalies aft on it even in the moift way. 5. Baryt, alfo termed from its high fpecific gravity PONDEROUS EARTH, is not found pure; but when it is obtained pure, by the aftion of a ftrong heat on it in combination with nitric acid, it is more cauftic than lime, ai.d abforbs water eagerly, forming a very tenacious ce- ment. When covered with water it is diflblved with a hitting noife, and cryftallizes in tranfparent needles, forming 3. compnges like beaten plafter. Cold water difTolves 3 zcth n part of its weight, and boiling one-half. It is alfo foluble in alcohol, and is dieadfully poiionous.----Annals dt Chimie, xxi. It is not fufible alone but is afted on by the fame fluxes as lime. It has the greateft affinity with muriatic acid, of all alka- line or earthy fubftances. The fulphate which precipitates on the addition of fulphuric acid to its folution in the nitric or muriatic acids, requires 40,000 times its weight of water for its folution. 6. STRONTrAhas not been found pure; when obtaincl fo by art ir is more foluble, and fpecifically heavier than lime. It is vifibly precipiiated from its folution in 200 parts of water, yielding comprefled rhomboidal cr)ftals. It does not feparate lime from acids. It diffolves readily in the nitric and muriatic acids, and forms by the addition oii the fulphuric, an infolubie precipi- tate : it decompounds in the moift way, all the faiihe com- pounds of the fulphuric acid. Alone it does not fufe, only glitters with a phofphoric flame ; but it may be fufed if it be mixed wnh moft of the o.her earths. 7. Jargonta, is found in the ftone called JARGON, from Ceylon, and in the Hyacinth. It pofltffes roughnefs and haidnefs refembling filica, but in many refpefts refem- bles alumine. Sp. gr. exceeds 4,000. It appears to be infolubie in water. It unites with the carbonic, nitric, and fulphuric acids, but is precipitated from the laft by the alkalies, and the other earths. When precipitated by the cauftic alkalies it retains a quantity of water, which imparts to it the ferni- tianfparency of horn, which with its colour and fracture gives it the appearance of gum arabic. It is infufible alone, but melts with borate of foda. Neither the alkalies ncr the alkaline phofpbatcs aid its fufion. 8. Glucine was difcovered by Vauquelin in the beryl, or aoua marina, and in the emerald. It is foluble in the fidphuric acid in excefs, and in the carbonate of ammoni- ac. It decompofes aluminate*, and is completely precipita- ted from its folutions by ammoniac. Its affinities for acids appear to be intermediate, between thofe of magnefia and alumine. Its falts are of a fweelifh tafte, from which cir- euoiftance it derives its name. B-*. 18 9- Agustine Is an earth which, as its name imports, forms, with acids, falts which are taftelefs. It was found by Trommfdorff in a mineral refembling the beryl. This earth refembles alumine, in not being afted on either by the fixed alkalies or ammoniac. It is not foluble in water; and by fire it acquires hardnefs, but no tafte, and fuffers no change in its folubility in acids. Superfaturated with phofphoric acid it yields a fait of eafy folubility ; but its ful- phate and acetite are very difficultly foluble. Guyton has obtained unequivocal proofs, not only that there exifts among the earths a tendency to unite both in the dry and humid way ; but alfo that with regard to fome of the earths, the union is fuch as to be capable of re- fifting an addition of acid in excefs. Guyton alfo obferves, that the aftion which Baryt, Strontia, and Lime exert on oils, foaps, and animal matters, with their union with the Pruffian colouring prin- ciple, fulphur, and the acids, form fo many points of refemblance with the alkaline fubftances. But he does not feem to think they are fufficient to warrant a common claffi- cal denomination.----Annates de Chimie, xxxi. Ingenhouz, Humboldt, and Van Mons, obferved that the earths, being moiftened, poflefled the property of abforbing oxygen from the atmofphere at the ordinary temperature. M. Girtanner difcovered, that by the application of heat this effeft was confiderably increafed ; and that with a tem- perature much exceeding that of the atmofphere they would Separate oxygen from water. Alumine attrafts it with the greateft avidity, at a temperature much below that of boiling water. Lime requires a higher temperature, and then does not abforb fo much oxygen. Silica requires a red heat, and then it feizes it rapidly. The avidity with which oxygen is abforbed by lime, accounts for the unhealthinefs of rooms, the walls of which have been lately white-wafhed.——Annates de Cbir mje, xxxiii. MO — OF CALORIC. HEAT, with the Various changes produced by it in bodies, is confidered by fome, as merely the confequence of certain mechanical changes in bodies 3 but it is moft gene- rally fuppofed", that thefe effefts depend on a certain matter called Caloric, or the Matter of Heat. Caloric appears to be an highly elaftic imponderable fluid; and is fo very fubtile, that neither has its gravity been yet afcertained, nor its exiftence, in a simple and un- combined ftate been fhewn. It combines chemically with all bodies, in a quantity proportioned to their affinity with it. By its elaftic power it conftantly tends to feparate the particles of matter, in which it is oppofed by the attraftion of cohefion : hence, attraftion of cohefion predominating, the body exifts in a folid form : caloric exifting in fuch a proportion as to weaken the attraftion of cohefion to a cer- tain degree, the body affumes a liquid form; and when the quantity of caloric is increafed (till farther, the body takes a gafeous form. It conftantly tends to form an equilibrium, by pafling from bodies of an higher, and diffufing itfelf through bodies of a lower temperature. Bodies, which thus tranfmit caloric, are termed con- ductors of caloric; and according to the power of doing this, they are termed good or bad conductors. Two bodies of the fame nature, unequally heated, on being brought into contaft, foon arrive at an equal tem- perature, the caloric becoming equally divided between them. But when two bodies, differing in their nature, and differing in the quantity of caloric they poffefs, are thus allowed to form one common temperature by communica- tion, this will not be found to be an arithmetical mean between the two original temperatures; but the one will be found to have required a greater or a lefs quantity of caloric than the other, to render it of the common temperature. . At the moment of the chemical union of two different fubftances, the new compound, not perhaps having the fame affinity with caloric as its conftituents, muft either yield a part to neighbouring bodies, or receive it from them ; producing thereby a change in their temperature, which is increafed in the former and diminifhed in the latter cafe. The property by which bodies require different quantities of caloric to produce the fame temperature has been termed the capacity for heat; and the quantity of caloric thus required, fpecific heat. The caloric thus abforbed, is termed combined caloric, or in the language of the celebrated Dr. Black, latent heat. But when it is perceptible by the organs of feeling, it is termed free caloric, or according to Dr. Black, fenfibU beat. 2D' The caloric which enters into the compofition of bodies may be chemically combined, or only adherent. In the- former cafe new combinations may extricate the combined caloric; but in the latter, mere mechanical preffure, or a change in the ftate of folidity or fluidity in the body, may fuffice to fet it free. Thus bodies pafling from a folid to a liquid ftate, or from either of thefe to a gafeous form, abforb from the furround- ing bodies a portion of heat which becomes latent; entering into combination, as one of the neceffary conftituents of the body, in that ftate. Every fubftance alfo pafling from a ftate of vapour to that of a liquid, and from this ftate to the folid ftate, fuffers its combined caloric to efcape, which then becomes fenfible or free. . If a body be not of a nature to undergo fuch feparation of its parts, by the addition of caloiic, as may occafion an alteration of its form, ftill an increafe of its bulk or dimen- fions, proportionate to its increafe of temperature, will take place. On this principle are calorimeters, or thermome- ters, formed ; the point at which the mercury in the thermometer refts when placed in contaft with any body, fliows the degree of dilatation or contraction the merauy has fuffered, during the eftablifhment of an equilibrium between it and the body to which it is applied. The tempe- rature of the body being faid to be higher or lower according to the effeft thus produced. Mr. Wedgwood conftrufted a pyrometer-on another principle. It is compofed of pieces of n.cely gauged clay, which contraft by the higher degrees of heat The fcale begins at vifible rednefs, and the extreme heat of a good air furnace of the ordinary conft;uftion is 1600 of his fcale or a little mere. Ice imb.bes the caloric communicated to it by other bodies, until it has abforbed fufficient to render it fluid, the temperature of thefe bodies defcending proportionally. From this circumftance we not only derive a proof of the difference of capacity for caloric, in different bodies, but are alfo enabled toafcenain the rd..tive quantities of caloric they con- tain. Forfince equal quantities of calcic will liquify equal quantities of ice, the quantities of ice liquified by equal' quantities of different bodies, will be proportioned to the quantity of caloric thofe bodies parted with ; and will therefore point out the quantities of fpecific heat they con*- tained, a;id their refpeftive capacities for caloric. 21 Count Rumford, from the great quantity of heat produ- ced by friftion, is induced to afk, What is heat ? Is there any fuch thing as an igneous fluid ? Is there any thing that can with propriety be called caloric ? He obferves, the fource of the heat generated by friftion, appears evidently to be inexhauftible ; and adds, that any thing which any infula- ted body, or fyftem of bodies, can continue to furnifh with- out limitation, cannot poflibly be a material fubftance. He concludes it to be almoft impoffible to form any diftinft idea of any thing capable of being excited and communica- ted in the manner that heat is excited and communicated, except it be Motion.——Phil. Trans. 1798. Heat, Mr. Davy fays, or that power which prevents the aftual contaft of the corpufc'es of bodies, and which is the- caufe of our peculiar fenfations of heat and cold, may be defined a peculiar motion, probably a vibration of the cor- hufcles of bodies, tending to feparate them. It may with propriety be called the Repulsive Motion. The nonexiftence of caloric, or the fluid of heat, he thinks his ex- periments havs proved. Dr. Beddoes is alfo of opinion that moftof the phenomena relative to heat, .are more eafily reconcileable to the mecha- nical than the chemical doftrine of heat.—Contributions to Phyjieal and Medical Knowledge, 1799. This portion of caloric, according to Gren, is only really calorific, or producing warmth, the expanfive force of which isaftive; hence the temperature of a body, he thinks, de- pends principally on that portion of free caloric, which is ftreaming through and iffuing from it. OF LIGHT. LIGHT is an elaftic fluid, being reflected from bodies that it cannot penetrate, in an angle of refleftion equal to its angle of incidence. It is.projected in every direction from radiant bodies, pafling through 167,000 miles in a fecond. In its paffage near any other fubftance, it is af- fefted by attraftion, and fuffers a greater or lefs degree of infleftion. In its paffage from one medium into another of a different degree of denfity, it fuffers refraclion, or a change in its direction. Combuftible bodies poffefs the greateft refracting power, 22 Solar light is divifible by the prifm into feven primitive rays, in the following order; red, orange, yellow, green, blue, indigo, and violet. It is alfo poffeffed of chemical affinities, by which it enters into combination with other fubftances; fometimes occafioning their decompofition, and fometimes being itfelf extricated from its combinations. It is fuppofed to yield to vegetables their colour, and to contri- bute much to their odour, tafte, combuftibility, and refinous principle. It alfo enables vegetables to emit torrents of pure air. In fact, it poffcfl'es fuch numerous chemical affinities, that there hardly exifts any fubftance which does not undergo a change from its prefence or abfence, Sugar, borax, filiceous ftones, and many other fubftan- ces, yield light merely by • attrition ; other bodies yield it upon being heated. This property has been termed Phos- phor ifm. Spallanzani fuppofes the fplendor of natural phofphori to depend on a flow combuftion. The Editors of the Critical Review objeft to this opinion, confidering light as diitinft from heat. Humboldt thinks the prefence of oxygen gas is neceflary to the phofphoric appearance of putrid fubftances. Mr. T. Wedgwood found that the phofphorifm of almoft all bodies m;ght be made apparent, either by heat or by attrition. By placing them on a plate made-nearly red hot, he obtained a phofphoric light, not only from different combi- nations of earths, and other fubftances which might be expected to poffefs this property; but alfo from pieces of white paper, linen and woollen, hair-powder, faw-duft, wax and oils. The light yielded by bodies upon attrition, he conjectures, may be attributed to a fudden heating (red hot) of particles in their furfaces.----Phil. Tranf. 1792. Some think with Epicurus, that Light is a continual emanation of the luminous body, which throws to a diftance a portion of its fubftance : and this is the emiffion of light adopted by Newton. Others, with Euler, think it is dif- fufed throughout infinite fpace, and is afted on by luminous bodies, as air is by fonorous bodies. Some believe it to be an elementary body, and others confound it with fire. Richter believes it to be compofed of the inflammable prin- ciple and caloric.—Prevoft, and others have even endeavour- ed, but in vain, to eftimate its gravity. Some have doubted whether light is not merely a modifi- cation of caloric ; and many connect them as caufe and effect. Dr. G. Pearfon defcribes fire as confifting of caloric and light; and confiders light, not as a diftinft fpecies of mat- Xer, but as a ftate of caloric, which is manifefted by its producing the fenfation termed vifion. Phil. Journal, and Phil. Tranf. 1797. Count Rumford concludes from his experiments, that the vifible changes produced in bodies by the aftion of the fun's rays, are effected, not by any chemical combination of the matter of light with fuch bodies, but merely by the heat which is generated, or excited, by the light that is abforbed by them.—*—EJfays on Heat. OF OXYGEN. OXYGEN, or the acidifying principle, is found only in its combinations, which from its almoft univerfal agency in the operations of nature, are neceflarily numerous. It is abfolutely neceffary to refpiration and combuftion, and likewife poflefTes exclufively the property, from which its name is derived, of forming acids by combination with certain fubftances, which are therefore termed acidifiable bafes. Acids, the refult of this union, are charafterifed by a four tafte, and by changing vegetables red. By their union with other fubftances hereafter mentioned, they form peculiar salts. The general characters of thefe are fapidity, ready folubility in water and incombuftibility. Acids may exift in three ftates of combination with oxy- gen—ift, When their oafes are not faturated with oxygen, which is defignated, according to the prefent nomenclature, by the termination ous* 2dly, When completely faturated with oxygen, which is pointed out by the termination ic; and jdly, When poffeffing an excefs of oxygen, when the fub ftance is faid to be oxygenated. When metals and various other fubftances are expofed to its action, the acidifying procefs fometimes takes place unaccompanied by the ufual marks of combuftion, and in fuch a degree as not to produce obvious acidity. The fub- ftances we then called OXIDES, to denote their being in a ftate approaching to acidity, and the procefs is termed OXIDATION. Oxygen Gas is the refult of the combination of oxygen with caloric. It exifts in atmofpheric air, in the proportion 24- ©F 17 to 100, and is more ponderous than the aif of the atmofphere, in the proportion of 45 grains in the cubic foot; its fpecific gravity being to that of common air, at 1103 to 1000. COMBUSTION is a procefs in which this gas is decom. pofed, the oxygen is abforbed and fixed by the burning body, which has its weight thereby increafed, and its nature changed, whilft the caloric, being difengaged, paffes off in the ftate of fenfible heat, and fometimes with fuch a portion of light as gives the form of flame, or the appearance of red heat. From the abforption of oxygen during combuftion, acids are formed. Ignition is faid to take place when a red heat accompanies this procefs, without the appearance of flame; inflammation, when light is evolved in the form of flame ; and detonation, when inflammation occurs with great rapidity and noife. So high a degree of temperature may be produced by the accefs of oxygen, that by a ftream of inflamed oxygen gas, fubftances, otherwife refraftory, maybe eafily fufed. The application of a body already igni td is in general neceffary to commence the procefs of combuftion in another; but in fome cafes even inflammation is the refult of the mix- ture of two cold fluids. Some fubftances, by fome hitherto inexplicable action of their conftituent parts on each other, undergo a fpontaneous inflammation. This has been found to be the cafe with hemp, lamp-black, pr wool, with linfeed oil ; alfo bran of rye, torrefied root of fuccory, faw-duft of mahogany, py- rites, Sec.----See Nicholfon's Chemiflry, B. II. Seft. 5. From Oxygen Gas being abfolutely neceffary to refpi*- tion, it has been termed VITAL AIR ; it being abforbed during refpiration, by the blood in the lungs, which there- by acquires an augmentation of its vital powers, and becomes of a vermilion colour. Oxygen is plentifully emitted by vegetables during their expofure to light. But both thefe proceffes will be more fully examined when the other conftituents of air and of water have been treated of. It may be difengaged from its bafes by the action of light, and by the application of fuch fubftances as have a fuperior degree of affinity with thofe bafes, as will be fhown when treating refpectively of each. 23 OF HYDROGEN. HYDROGEN, as its name imports, contributes to the -formation of water. It has only been obtained in combi- nation. Hydrogen Gas, fometimes termed Inflammable Gas, is formed by the union of Hydrogen with Caloric. It is about 12 times as light as common air, being thelighteft of all the gafes we know ; and has a difagreeable odour, which it lofes when deprived of the water which it holds in folu- tion, in a quantity equal to half its weight. It is abforbed by vegetation, and is then fuppofed to be,- tome one of the conftituents of oil, refin, &c. It is not fitted for refpiration, though not immediately injurious. When by itfelf, it extinguifhes flame; but being mixed •with oxygen it burns with brilliancy, when any body, already ignited, is brought into contaft with it. It is pro- duced by the refolution of animal and vegetable fubftances, in all which it exifts as a conftituent principle. It is alfo obtained from feveral mineral fubftances, by certain chemi- cal procefles; it containing various impurities, according to the fubftances from which it is obtained. Water is formed by the union of hydrogen and oxygen. The proof of its compofition is thus obtained : water in a ftate of vapour, being made to pafs over iron wire twifted ""and made red hot, the iron is oxidated, a confiderable por- tion of the water difappears, and hydrogen gas is produced; the iron depriving the water of its oxygen, by which it becomes an oxide, whilft the hydrogen combining with caloric, forms the hydrogen gas. Again, 15 parts of hy- drogen gas being burnt in a clofe veflel with 85 parts of oxygen, water is formed of the fame weight as the gafei employed. It appearing that, at a temperature lower than that of ignition, the attraftion of the refpeftive bafes of the two gafes to caloric is ftronger than their attraction to each other, which prevents their decompofition. But that at the degree of ignition, the attraftion of the bafes are ftronger to each other than to caloric; hence they unite and form water, the caloric and light being d fengaged with flame. The compofition of water by the ponderable part cf thefe gafes is beautifully evinced by the experiments of Dr. Pear- fon, by means of the electric fpaik. C 26 Water i» an uninflammable fluid, and when pure, is tranfparent, colourlefs, and void both of tafte and fmell. It enters into the compofition of moft bodies in the animal, vegetable, and mineral kingdoms, either in a ftate of com- bination, or of fimple mixture; contributing to the'hard. oefs and tranfparency of fome bodies, as faline or ftony cryftals, and giving fixity to others, as the acids. At the temperature marked by 32° F. water parts with ■caloric, has its volume increafed by a confufed ciyftalliza- tion, and affumes a folid form, when it is -termed ICE, The temperature being increafed, it re-affumes the liquid form of water, in which a confiderable quantity of caloric becomes fixed, and is prevented from pafling into a ftate of vapour by the preflure of the atmofphere. But if, in the moft common ftate of the atmophere, the water be heated fo that the intenfity of caloric be raifed to a degree marked by 212* F. it then boils, and is converted into an elaftic fluid, or AQUEOUS VAPOUR. By certain natural procefles the atmofphere is conftantly impregnated with this vapour. When in confequence of cooling or compreflion, the caloric ieparates from the finely divided particles of water, which formed the bans of the vapour, and which now approximate to form a liquid again, the appearance termed FOG, or MIST, takes place, and in the higher regions, CLOUDS are formed from the decern- pofed vapour, the ftill nearer approximation forming RAIN. Thus alfo may be explained the formation of DEW, and of water on the walls or windows of crowded rooms. By the more rapid fubffraftion of caloric the production of HAIL, and of HOAR-FROST may be alfo eaiily accounted for. Water generally contains fore;gn fubftances, and when thefe belong to the mineral kingdom, the waters fo impreg- nated are termed MINERAL WATERS. The following table points out, in a general way the contents of thole which "have excited jnoft notice by their medicinal pro- perties. o , ,, S Malvern. S.mple cold waters......... J Holywell. f Briftol. Simple thermal....... . . . . -j Matlock. Simple faline, containing chiefly J ■& r .1 • r 1. 1 Epfom, neutral purging ialts....../ gf Buxton. Sedli Epfo Sea, Highly carbonate alkaline . . r . . . . Seltzer, Simple carbonate chalybeate.....Tunbridgev Hot carbonate chalybeate.......Bath. Highly carbonated chalybeate • • • | Pyrmonf. » ,. . , . i ^ K Cheltenham.. Saline, carbonated chalybeate r . . < Scarborough Hot, faline, highly carbonated f Vichy. "■ chalybeate ........... I Carlfbad. Vifrtolated ehalybeate......... HartfelL ~ ., ^ , » S Harrogate. Cold fulphureous......... J Moffatt. f Aix. Hot, alkaline, fulphureoui ►..»-< Borfet. t Barege. Dr. Saunders's Treatife on Mineral Waters, 1*00, NITROGEN. NITROGEN, or Azot, the Nitric Radical, or acidifiabh hafls of nitric acid, has only been obtained in a ftate ef com- bination. Nitrogen Gas, which has alfo been termed azotic gas, cr atmofpheric mephitis, is formed by the combination of nitrogen with caloric. It forms more than two-thirds of the air of the atmofphere ; but alone, deftroys animal life, and ftops comhuftion. It may be obtained from the atmof- pheric air, when, by the ox;dation of metals, by combuf- tion, or by any other procefs, the other conftituent of the air, the oxygen gas, has been abforbed. It is obtained from moft bodies in the vegetable and animal kingdom, nitrogen exifting in thefe as a radical principle. It is light- er than common air, in the proportion of 985 to 1000, and is not in the leaft acid, or foluble in water. Nitrogen, as its name impons, is the chief con-* ftituent, the bafe, of the NITRIC ACID ; an attention to the following proceffes will render th's fufficiently manifeft. Nitre being dift.lied with half its weight of acid of ful- phur, a yellow acid liquor yielding reddifh fumes, is ob- tained ; as thefe fumes are feparated the liquor lofes its colour, and ceafes to fmoke. This change is effected 2S in lefs t'mt by the addition of heat or of water, the fume* be:ng difperfed rapidly in both cafes, and in the latter thi liquor becomes firft green, then blue, and laltly white. Nitric Acid, or Aqua Fortis, is the colourlefs liquid juft defcribed, in which the acid exifts in a ftate of complete oxygenation. In proof of which, nitric acid being paffed through a red-hot glafs tube, is refolved into oxygen ga», and nitrous acid. Mr. Cavendifh has manifefted the compofition of ni- tric acid, he having formed it by taking reiterated electrical fparks through a mixture of oxygen, and of nitrogen gas. Nitros Acid, or Glauber's fuming Spirit of Nitre, is the yellow fmoking liquor }uft mentioned.. In this a portion of the nitric radical exifts not combined with a full proportion of oxygen, and this fuboxidated portion flying off a flumes a, reddifh colour on meeting with oxygen, which if does in the air of the atmofphere ; becoming by this accefs of oxygen, nitros acid gas, and-on be- ing abforbed by water it changes to nitric acid. The acid from which it has efcaped alfo becoming perfect, or nitric acid. Nitrous Gas is a combination in which the nitric ndical exifts in a yet lower ftate of oxidation. It is produced by mixing with the nitric acid, charcoal, iron* brafs, copper, or any other fubftance which will attract its oxygen, the atmofpheric air being carefully excluded,. The gas thus obtained holds fo fmall a portion of oxygen as to manifeft no acid properties. It is colourlefs, and will fupport neither animal lite nor combuftion. On meeting with atmofpheric air it is converted into the reddifh yellow vapours already defcribed, as convertible into nitric acid by the contact of water, evincing that by the combination of. oxygen and nitrous gafes nitric acid is generated. Its compofition is proved by burning pyrophori in it, the oxygen being abforbed during combuftion, leaving unmixed nitrogen-gas. Gaseous Oxide of Nitrogen appears to be the refult of a ftill lower degree of oxidation of this radical. It is obtained by expofing nitrous gas to we'ted iron filings, or moift fulphuret of alkali; or any other fubftance which ab- ftrafts a portion of the oxygen. Mr. Davy obtained this Nitrous Oxide by decompo- fing nitrate of ammoniac at temperatures below 44.00. It is heavier than air, and is foluble in double its quantity of water, and when given out again pofleffes its former proper- ties. It yields a fweet tafte, and a flight but agreeable 29 •dour, and does not manifeft aftual acid properties. It is decompofable by combuftible bodies at veiy high tempera- tures, is combinable with alkalies, but is infolubie in moft of the acids. If an acid, Mr. Davy fays, it is the weakeft of the acids ; but ought rather to be confidered as a body fui generis. He found it to be refpirable, producing ex- traordinary effects on the nervous fyftem. From Mr. Davy's experiments it appears that Nitric Acid contains oxygen in the proportion of 2,389 to 1 of nitrogen ; bright yellow nitrous 2,344 5 orange coloured 2,292 ; and dark green 2,230. Nitrous Acid, he thinks with Mr. Thompfon, is nitric acid holding nitrous gas in folution, and that the falts,- termed nitrites, muft be ternary combinations, confifting of nitric acid, nitrous gas, and falifiable bafes. Nitrous Gas, he finds, is compofed of 56 oxygen, and 44 nitrogen. Nitrous Oxide, he fays, confifts of 37 oxygen to 63 nitrogen.——-Refearches Chemical and Philofophical, 1800. The nitric acid unites with oils> and forms with them a fnb-refinous fubftance, fbraewhat refembling mufk, fome- times producing inflammation. It rapidly corrodes organi* bodies, ftaining fkin, hair, and other animal matters, of a permanent yellow : and oxidates iron, zinc, copper, &c. very fpeedily, nitrous gas> as already obferved, being at the fame time formed. From the facility with which, nitric acid parts with its oxygen, it is employed as a proper vehicle in which the oxy- gen may be applied to certain ac-difiable bafes, to procure the peculiar acids of thofe radicals. For this purpofe the nitric acid i6 added to the fubftance, Containing the radical or bale, and diftilfed from it, it pafling over in the ftate of nitrous acid, nitrous gas, or even nitrogen, according to the quantity of oxygen which has been iubtrafted from it by the acidifiable bafis, now rendered a peculiar acid. Thus are acids obtained from fugar, arfenic, &c. as will behere- after Jhown. Mr. Mayer firft conjectured that nitrogen was compofed of oxygen and hydrogen—a water changed into p:. Gren"s Journal, vol. v. Mr. Girtanner finding nitrogen gas produced by pafling water through tubes of heated earth, concluded that the oxy. gen of the water partly united itfelf with the earth, forming an earthly oxide, and that the remainder, ftill united 4o C 2 30 hydrogen, combining with caloric, formed the nitrogen gas. He therefore defcribed nitrogen as 'water deprived of a fart of its oxygen, and confidered it, with Mayer, as a com- pound of oxygen and hydrogen, terming it an oxide of hydro- gen.——Ann. de Chim. No. 100. Berthollet agrees, with Dieman, Van Trooftwyk, and Lauwrenberg, in denying this formation of nitrogen gas from water ; and in aflerting, that it proceeds from the ex- terior air, deprived of its oxygen gas, by the fire in which the tubes are placed.-----Aim. de Chim. No. 103. Dr. Mitchell, of New-York, fuppofes the matter of peftilence to be Septon (azote,) chemically united with oxygen, bafe with bafe, before they had attracted caloric enough to convert them to gafes, and give them the repel- lency incidental to that condition, as is the cafe when the two diftinft gafes are merely mixed, as in atmofphe^i* air. The doftor employs the term fcpton, for nitrogen. Septotts gas, for nitrogen gas. Septic gas, for nitrous gas, &sc. The Doftor contends that the nitric acid is, in fact, a mixture of the muriatic and fulphuric with the feptic, (nitric,) and that nitrous air, nitrous oxide, &c. are fimilar farragoes. The Critical Reviewer obferves, that nitre obtained from the air has, indeed, always a proportion of muriatic acid, and that fulphuric acid gains admiflion during refining, but that thefe are accidental ijnpurities, not component parts.— Crit. Rev. Aug. 1800. Atmospheric Air, that franfparent, colourlefs fluid, which every where invefts this globe, poffeffing permanent •lafticity and gravity, is compofed of nitrogen and oxygen gas, in the proportion of 73 of the former, and 27 of the latter, in a ftate of mixture, not of intimate combination ; and is foluble in about 30 times its bulk of water. The conftituent principles of atmofpheric air are rendered evident by the following experiment. Quickfilver being inclofed in a proper vefiel of atmofpheric air, on heat being applied, the air will be diminifhed, and the quickfilver lol'e its fplendour, and gradually change to a reddifti powder; acquiring, at the fame time, an augmentation of weight. Whe» neither the air nor the quickfilver fuffers any farther change, the feparation of the principles has taken place : the oue, the gas remaining in the receiver, is now unfit for Supporting flame, or maintaining refpiration, and is nitrogen 31" gas; the other is abforbed by the quickfilver, whilft redu- cing to the ftate of an oxide, and may be extricated from it on the application of heat: when the powder, to which the quickfilver is reduced, will be reftored to its metallic ftate, but will have loft the weight it had gained during its oxida- tion ; this deficiency being exactly equal to the weight of the evolved gas, which is oxygen gas. Thefe feparated gafes, thus differing in their properties from each other, and from atmofpheric air, being again mix» ed, form atmofpheric air of the ordinary degree of purity. Atmofpheric air contains in every ioo parts,, 27 of oxygen, and 73 of nitrogen gas. It muft, however, be acknowledged, that in thus form* ing refpirable air, an aeriform fluid, is obtained, differing in fome trifling refpefts from the ordinary air of the atmof- phere, F. Von Humboldt fuppofes that our not being able to form an aeriform fluid, perfeftly fimilar to that of the at . mofphere, does not proceed from our ignorance of the quan- tity or quality of the gafeous bafes, but from a difference in their union ; that in the atmofphere they may be confider- ed as in a ftate of chemical combination, but in the artifi- cial, merely as a mixture.——Journal de Pbyflque, 1798. Refpiration and combuftion depending on the prefence of oxygen, thefe proceffes will always be affefted by the pro- portion in which the oxygen gas exifts in the air in which they are performed. The atmofphere alfo contains foreign matters, fuch as other gafeous bodies, water which it holds in folution, minute detached particles of bodies, &c. From the avidity with which nitrous gas abforbs oxygen to form nitric acid, it has been employed by Prieftly, In- genhoufz, and Fontana, as an Eudtometer to meafure the quantity of oxygen in the atmofphere; the diminution of volume in a. given quantity of atmofpheric air, to which the nitrous gas is applied, giving the quantity of oxygen abforbed, and the quantity which the given quantity of at- mofpheric air contained- But the refults of thefe experiments are not always the fame, nor can it be faid how much of the diminution is at- tributable to the concentration of the nitrous gas itfelf. Combuftion with hydrogen gas has alfo been employed for the fame purpofe by Volta, and with more precifion ; but it requires a more complicated apparatus, the refults are not conftant, nor can it be afcertained how much of the dimi- nution is to be attributed to the hydrogen, and how much" to the oxygen gas. By the expofure to a liquid fulphuret of alkali, a more- correct comparifon of different airs is obtained, the whole diminution being attributable to the oxygen gas ; but this afts very (lowly, nor can it be known even after feveral days that the procefs of diminution is completed. Guyton pro- pofes to employ dry and heated fulphuret of alkali. Gren and BertholleL recommend the meafure of the oxy* gen to be obtained by the combuftion of phofphorus in the air intended to be examined. The gravity or preffure of the atmofpheric air varies at different times. To mark this variation an inftrument call- ed the barometer is employed. This inftrument is a tube containing a column of mercury 28 inches in height,. which is known to be the exaft counterpoife of a column of air of the height of the atmofphere. This tube being open at the lower end, and having a vacuum above, the mer- cury rifes and falls in it according to the varying preffure of the circumambient fluid. The atmofphere alfo varies as to the quantity of water it contains. To eftimate this variation hygrometers are employed, which are formed of fubftances which readily fhrink by drynefs, or fwell by the application of the fmalk eft quantity of moifture. Alkalies,* whofe general charafteriftics are, 1, an acrid, urinous tafte; 2, changing the vegetable blues greeny 3, combining with acids, and forming neutral falts; 4, fa- cility of folution in water ; appear to be derived from nitro- gen, which has therefore been efteemed the alkaligen princi- ple. They are divided into volatile and fixed. Ammonia, or the Volatile Alkali. This has been proved to be a compound of nitrogen and hydrogen. It feems to owe its origin to animal and vegetable decompofition. It is diftinguifhed from the other alkalies by its pungent finely * By treating of alkalies in this place, they are not only confi- ilered in connexion with one of their fuDPofed principles, but a knowledge of their refpedtive natures is acquired, previous to an examination of neutral farts, and other combinations of which they form a part. ' Dr. Pearfon recommends to employ the ancient name alkali for the genus, and the ancient names of thefe falts for the fpecies, ab- breviated thus into one word, viz. Veg-*lkali, Faf-alhJ, and Vol- alkali.——Cbimicvl Nomenclature* 3$ and great degree of volatility. 1000 part9 contain 807 of nitrogen, and 193 of hydrogen. Alkaline Gas is formed by the combination of am- moniac with caloric. It is lighter than common air, is un- fit for combuftion, the flame enlarging before it is extin- guished. It deftroys animal and vegetable life; its other properties refemble thofe which have already been attributed to ammoniac. Fixed Alkalies have for their peculiar charafteriftics,, »ft, Their not being volatilized by the moft intenfo heat. 2dly, The rendering oils mifcible with water, jdly, The forming grafs, when fufed with flinty fubftances. Analogy, and even experiment, lead to the conclufioix that fixed alkalies are formed by the combination of nitro- gen, with fome unknown bafis,. probably earth. Pot ash, or the Vegetable fixed Alkali, is obtained bf wafhing the afhes of burnt vegetables* or of the lees, or of the tartar of wine. When obtained from the two latter fubftances it ha-s been called the Salt of Tartar, and when it has become fluid by imbibing moifture, it has improperly been termed Oil of Tartar, per deliquium. It is conjectur- ed by Fourcroy, that pot-afh is the refult of the combina- tion of nitrogen with lime Soda, or the Mineral fixed Alkali, is fometimes found in a native ftate, but is in general obtained by the combufti- on of maritime plants, particularly of the kelp, and of the fea-graffes, and fea-tang. It differs from pot-afh, in not being deliqueicent, and in cryftallizing in rhomboidal ofta*- hedions ; but the chief differences between them- are obfer- vable in their refpeftive combinations. Like the former, this alkali is fuppofed to be formed by a combination of n.trogen with fome other principle, whiclf has alfo been fuppofed to be an earth : this earth has been fuppofed to be magnefia-by Fourcroy and Lorgnai. Guyton concludes that lime is compofed of carbon, ni- trogen, and hydrogen; and magnesia, of lime and nitrogen j and that pot-ash is compofed of lime and hydrogen; and soda, of magnefia and hydrogen. GLASS is a combination of filica with fixed alkali. The mixture is firft well calcined, when it is called frit; then- after complete fufion it becomes glafs-metal; and the extra- neous falts which float on its furface are named glafs-galL When formed into the required fhapes, it is annealed or tern- fered by being placed in- a furnace of an appropriate beat. 34 The finenefs of the glafs depends on the purity and pro- portion of the ingredients. A fine cryftal glafs may be ob- tained from 16 parts of quartz, 8 of pur* pot-afh, 6 of cal- •ined borax, 3 of flake white, and one of nitre. By an over proportion of alkali, 4 to 1 for inftance, the glafs will become foluble in water, and even deliquefcent. Thus diffolved it is called liquor filicutrt, or liquor of flints. Profeffor Seigling having left a bottle of this liquor undif- turbed eight years, found tranfparent rock cryftals formed in it, which gave fire with fteel. From this folution, purs filica may be precipitated by the addition of any acid. Girtanner obferves, that in making glafs, a complete anal yds of the alkali is made, the hydrogen efcapes in the form of ga6, and the oxygen combines with the flint, th» glal's being nothing elfe but an oxide of filica. Profeffor Klaproth has difcovered the vegetable alkali in the foflil called leucite. It has alfo been found in lepidolite,- lava, pumice, and zeolite. Profeffor Abilgaart found that the pot-afh formed a conftituent part of animal blood ; and La Methei ie and Gren have difcovered the foffil alkali ia the falfula foda. NEUTRAL SALTS are formed by the union of the fete- ral acids with certain bafes. When the acids in thefe com- pounds are completely faturated with oxygen, it is defigna- ted by the word which deferibes them, terminating in ate, and when containng a more limited proportion of oxygen, by the termination of ite. Nitrates are Neutral Salts, formed by the combination •f nitric acid, with certain bafes. Nitrate of Pot-ash, Nitre, or Saltpetre, is produ- ced fpontaneoufly in various fituations, fometimes efnoref* cing on the furface of the earth*, and on the walls of old buildings; it is alfo found in fome vegetables, in mineral waters, dunghills, &c It may be artificially produced by the concurrent corruption, not ftriftly, putrefaction, of ani- mal and vegetable fubftances. Light earths, fuch as lirnt and marie, the refufe of foap manufactories, afhes, &c. be- ing ftratified^for this purpofe with ftraw, dung, and animal and vegetable fubftances; wetted with urin»> blood, dung- hill-watcT, and the mother waters of faltpetre; and turned and expofed to the current of air. When putrefaction takes place, the nitrogen uniting with hydrogen forms ammoniac ; but in this ftage of coluption,. in which nitre forms, the nitrogen as it is extricated com- bines with oxygen, which is alfo feparated, and forms ru- 55 trie acid. This on its formation meeting with fome earthy or alkaline bafe, inftead of efcaping, becomes fixed in a neutral fait. Nitrate of pot-afh cry ft a likes in hollow ftria- ted hex«hedral prifms, terminating in hexahedral pyramids. It yields a pungent tafte, and impreffes thefenfation of cold- nefs on the tongue. It is foluble in 7 parts of cold and 1 of hot water. By diftillation, it yields 12000 cubit inches of oxygen gas for every pound of nitre, cauftic or pure al- kali being left behind. Thrown on burning coals it yields a white flame, and fufes at a moderate heat, from the wa- ter of cryftallization it contains. If fufed until its water •of cryftallization is diflipated, and caft into moulds, it be- comes what is called cryflal mineral, or falprunel. Mixed with an equal quantity of fulphur, and fufed in a red hot crucible, the fubftance called falpolycrefl is formed. Charcoal at the temperature of ignition totally decompofes the nitric acid. Nitrate of pot-afh and charcoal therefore being mixed in a ftate of ignition, this decompofition takes place with detonation. This experiment being made by detonating 1 part of charcoal and 3 of nitre, in a proper veffel, the nitric acid difappears; the carbon takes from it oxygen, forming the carbonic acid, part of which is found in the form of gas, and the other part is united to the pot- afh of the nitre, forming a carbonate of pot-afh, which re- mains, and was formerly called fixed nitre, and in a ftate ^of folution in water, liquid fixed nitre, or Glauber's uni- werfal alkahefl: the acidifiable bafe or the nitrogen forming a nitrogen gas. The above process being performed in clofe vefTels, a li- quor diftils, which is fometimes impregnated with nitroul acid and ammoniac, and has been called clyffus of nitre ; car- bonate of pot-afh remaining in the retort, in confequence of the oxygen combining with the inflammable body, by which en acid is formed, which uniting with the pot-afh of the ni- trate, forms a new neutral fait. 100 grains of nitrate of pot-afh is found to contain jo of acids, 63 of pot-afh, and 7 of water; and a mixture in this proportion, will, on e- vaporation, yield cryftals of the pureft nitre, formerly call- ed regenerated nitre. Acidulous Nitrate of Pot-ash, or Nitrated Nitre, is formed, if the nitiic acid be employed beyond the point of faturation. Gunpowder is formed of 75 parts cf nitre, 16 of char- tool, and 9 or 10 of fulphur. The fulphur renders it more readily ignited. Thefe ingredients, duly moiftened, arc Z5 ground together in gunpowder-mills. The powder-pafle is afterwards grained, and for nice purpefes glazed. Its ex- ceffive power appears to proceed from the fudden generation of carbonic, hydrogen, and nitrogen gafes, aided by the vaft expanfive power of the immenfe quantity of caloric they in a moment fet free. Nitrate of Soda, Cubic or RbomboidalNitre, fo called From the form of its cryftals, is produced by the artificial combination of nitric acid with foda, it not having been found in a native ftate- It has a cool bitter tafte, {lightly attracts the humidity of the atmofphere, is foluble in 3 parts of cold water, and but little more foluble in bot water. It fufes on burning coals with a yellow flame ; its other properties refembling thofe of nitrate of pot-afh. 100 grains contain 28,80 of acid, 30,09 of alkali, and 21,11 of water. The fti ongeft nitrous acid is to be found in nitrated foda, ■ ■ Kirwan. Nitrate of Ammoniac, is formed either by the com- bination of the nitric acid gas, with amrnoniacal gas, or by adding nitre to a faturated folution of fulphate of ammoniac, which evaporated twice at about 2500, depofits fulphate of pot-afh in cryftals, and leaves a folution of nitrate of am- moniac, which at 212 forms in beautiful flexile needle-like cryftals, of a cooling but acrid tafte. Expofed to the fire, it fufes, dries, and then detonates. 100 parts contain 4.6 of acid, 40 of ammoniac, and 14 of water. Nitrates with earthy bafes. Nitrate of Lime, formerly termed Nitrous Selenite, is found adhering to, and embodied in, calcareous ftones, and diffolved in various mineral fprings. It is formed near inhabited places, and is yielded by the lixivation of old plafter, and by the mother waters of laltpetre, as they are termed by the manufacturers. It forms acrcular cryftals of a fharp and bitterifh tafte, which readily deliquefce, and are very foluble in water. It fufes when expofed to heat, part- ing with its acid in the form of nitrogen and oxygen gafes; the earth which remains, after the fire has been confiderably urged, is phofphorefcent, and is called Baldwin's phos- phorus. This fait being diffolved in alcohol, gives to it the pro- perty of burning with a red flame. The fixed alkalies and baryt precipitate the lime. Sulphuric acid unites with the lime, and difengages the nitric acid. 100 paits contaiu 4.3 of acid, 22 of lime, 35 water of cryftallization. 31 Nitrate of Baryt, has not yet been found native. It cryftallizes difficultly in oftahedral cryftals, and though deliquefcent, requires a confiderable quantity of water for its folution Neither alkalies, nor the other earths, decom- pofe it. But the fulphuric acid is detected in any mixture by this fait, fince by uniting with the baryt, fulphate of baryt, or ponderous fpar, is precipitated. By expofing this fait to a violent heat, pure baryt is left more cauftic than quick-lime. This fait gives to alcohol the property of burn- ing with a whitifh yellow flame. Nitrate of Magnesia, is found in decayed walls, &c It forms tetrahedral columnar cryftals, which tafte acrid and bitter, are deliquefcent and readily foluble, either in water or fpirit of wine. It is decompounded by lime, baryt, and fixed alkalies, and by the fulphuric and fluoric acids. In ioo parts are 36 of acid, 27 of magnefia, and 37 of water. Nitrate of Alumine forms in fmall prifms, which are deliquefcent, and give an aftringent tafte. In the fire they fwell, and are decompounded, lofing their oxygen. Alkalies, magnefia, and lime, decompofe this fait. Nitrate of Strontian forms octahedral cryftals, and gives to the flame of alcohol a bright carmine red. Nitrites, or neutral falts formed with nitrous acid have been very little attended to. OF SULPHUR. SULPHUR is a fimple, inflammable, acidifiable, brittle fubftance, yielding a peculiar odour when heated, and ma- nifefting electric powers on being rubbed. It is found in and on the furface of the earth, both pure and in a ftate of mixture. It is faid alfo to exift in certain vegetables, and to be feparated during the putrefaftion of animal and vegetable fubftances. It is cleared from its im- purities by fublimation, excluding the external air to pre- vent its inflammation, when it is termed fublimed fulphur, or formerly flowers of fulphur. By a moderate heat it may be fufed, when it will cryftallize in thin needles, moftly of an oftahedral form ; and in this ftate it may be poured into moulds, and formed into rolls or flicks. D 38 "Neither nitrogen, nor carbon, have any apparent attraction to fulphur ; nor is it afted on by water; but that hydrogen may enter into union with it will appear from the combina- tion next mentioned. Sulphur combines with the fixed and volatile alkalies, and with all the earths, except alumine. The compounds being termed alkaline, or earthy sulphurets. Sulphuret of Pot-ash and of Soda, or Alkaline Liver of Sulphur, is obtained by melting two or three parts of the alkali with one of the fulphur. This compound is a hard fubftance, of a brown liver-colour, which foon im- bibes moifturefrom the atmofphere ; when it emits an odour refembling putrid eggs. This odour, which proceeds from a gas formed in confequence of the decompofition of the water, is alfo produced on its folution in water, for fulphur thus combined with alkalies or earths is enabled to attract the oxygen of the water, and form with it fulphuric acid, which combining with the alkali produces fulphate of alkali. The hydrogen of the water thus relinquifhed by the oxy- gen, takes up another part of the fulphur, and forms with it fulphurated hydrogen the bafis of this gas, but which be- ing retained by a feparated portion of the alkali requires the addition of an acid, and the aid of heat, to produce the fe- paration of the gas. The fulphur itfelf is precipitated in the form of a white powder, which has been called milk of fulphur ; its oxygen gas uniting with one part of the fulphur, whilft its hydrogen gas, diffolving alfo a portion, forms Sulphurated Hydrogen Gas, or Hepatic Gas, which is diftinguifhed by a peculiar difagreeable fmell. It blackens moft of the metals, and their oxides, deftroys life, renders violets green, and though it extinguifhes the flame of a lighted candle, it will itfelf bum with a light blue •flame, in contact with oxygen, depofiting, at the fame time, fulphur. If mixed with oxygen gas it unites with it, form- ing water and depofiting fulphur. The mineral fulphurous waters are formed by faturation with this gas. Sulphuret of Ammoniac, or, as it was formerly by-expofure fo air, falls to pieces ; but in time recovers its original hard- nefs, by re-abforbing carbonic acid gas. It is decompofed by almoft all the acids, by their fuperior degree of attrafti- on for lime, when other calcareous falts are formed, the carbonic acid efcaping in a gafeous form, and occafioning effervefcence. Acidulous Carbonate of Lime is formed by the folution of this carbonate in water impregnated with car- bonic acid. Carbonate of Baryt, Barolite, Kirw. Witherite, Werner. This combination has no tafte, is not altered in the air, is almoft infolubie in water, but is decompounded by heat, and by all the acids. It is found either in ftriated, compact, femitranfparent, white, or greyifh white maffes, or in hexahedral cryftals. Sp. gr. 4,3 to 4,33. 100 parts contain 0,80 pure baryt, 0,20 acid. Diffolved in water im- pregnated with carbonic acid, it is the moft effectual teft of the prefence of fulphuric acid.----Guyton. Carbonate of Magnesia, not fully faturated, or the magnefia of the fhops, is not found in this combination, but is obtained by precipitation with the carbonates of al- kali from the fulphate of magnefia. It is foluble in water, in the proportion of feveral grains to an ounce. It lofes its water and acid by calcination, the refidue being pun magnefia, fometimes called calcined magnefia. Cold water diflolves more than hot, it is therefore precipitated by heat- ing the folution.——Butini. When fully faturated with carbonic acid, it becomes more foluble, and by flow evaporation will cryftallize in hexa- gonal prifms with hexagonal fummits.——Gren. Magnefia, in powder, not faturated, contains magnefia 0,40, acid 0,48, water 0,12. In faturated cryftals magne- fia 0,25 acid 0,50, water 0,25.----Tabl. de Fourcroy, 1800. Carbonate of Alumine is formed by the acid of the carbonates of alkalies, combining with the earth thereby precipitated from a folution of alum. It has been found near Halle, in Magdebourg, and is alfo called lac lunaf. It varies in its proportions. Carbonate of Strontian is found at Strontian, in Scotland, formed in fmall ftriated hexahedral prifms, of a light green, and not quite opake. It melts into a green glafs, and gives the flames of coals a purple hue. Sp. gr. 3,658. It contains acid 0,30, ftrontian 0,62, water 0,08. It is only decompofable by baryt. Fourcroy. E 5rO Carbonate of Zirconia is infipid, and indiffoluble in water. It contains 55,5 of zirconia} and 44,5 of acid and water. Carbonate of Glucine is a light, white, iott and infipid powder, unchangeable in the air, foon lofes its wa- ter and acid in the fire, and is infolubie in water even though aided by its proper acid. Ammoniaco-magnesian Carbonate forms, when the two falts meet; it is ciyftallizable, and lefs foluble than the falts by which it is formed.----Fourcroy Tableaux Sy- nopliques, 1800. OF MURIATIC ACID. MURIATIC ACID, formerly termed Marine Acid, or Acid of Sea Salt, Sec. is conjectured, from analogy, to con- fift of oxygen, in combination with a peculiar, but hitherto unknovjn bafls.* It is obtained by diftillation, from a mix- ture of fea fait, with half its weight of fulphuric acid. The refiduum is fulphate of foda, fhewing the fea fait em- ployed to have been a neutral fait compofed of this acid and foda. When pure, it is colourlefs, and of a lefs fpecific gravity than the nitric acid. It has a peculiar fuffocating fmell, and copioufly emits vapours, which are rendered more vifi- ble by their mixture with the moifture of the atmofphere. It takes part of its oxygen from nitric acid. It does not aft on combuftible bodies, but feizes the oxygen of oxided bodies. It abforbs the carbonic acid, and its affinities with baryt, pot-afh, foda, ammoniac, lime, magnefia, and alu- mine, appear to be in the order they are here placed. Muriatic Acid Gas, is eafily obtained in this form! it lias a ftrong fmell, and is fliarp, without being cauftic. It is heavier than common a:r, extinguifhes flame, firft en- * Girtanner fuppofed this radical to be hydrogen; and Armtt thought it to be the metal zinc. Mr. W. Lambe fuppofes that fulphurated hydrogen is the bafe of muriatic acid, he having obtained oxy-muriatic gas by dropping fulphuric acid on the refiduum left, after evaporating water impreg- nated with hepatic g is, in which iroa and manganefe had been di- ccrted.- Maucbeftsr Mem. vol. v. 51 larging it, by a greenifh or bluifli circum-ambient flame. It fuffocates animals, and is unchangeable by light, caloric, or combuftible bodies. It unites with water with great ra- pidity and heat, forming the fluid muriatic acid. Oxygenated Muriatic Acid, is formed by the ad- dition of oxygen to the muriatic acid, which it feizes with avidity, whenever it is prefented to it. It is therefore readi- ly obtained by diftillation of the muriatic acid, from fub- ftances containing much oxygen ; fuch are the oxides of metals, particularly the native oxide of inanganefe. The acid is, in this ftate, of a yellowifh colour, of an auftere tafte, and of an exceflively ftrong difagreeable fmell; its va- pours irritating the larynx violently. It renders the blue colours of vegetables white, and thus deftroys the colour of moft fubftances, thereby lofing its oxygen. When about the freezing point, it cryftallizes, in quadrangular fpicular. It oxidates metals with rapidity, and thickens oils. By com- municating its oxygen to fulphur, it produces the fulphuric acid. Expofed to the light, oxygen gas is feparated, and ordinary muriatic acid is left; and as its lofs of oxygen is in a direct ratio of the quantity of light, the oxy-muriatic acid has been propofed as a PHOTOMETER* It feems to differ from the common muriatic acid, on the fame principle as the nitric and fulphuric acids differ from the nitrous and fulphureous j the fimple or the oxygenated muriatic acid appearing to be formed, according to the greater or lefs quantity of oxygen, united to the pure radi- cal. Dr. Gren, therefore, propofes the fubftitution of the terms muriatous for muriatic, and muriatic for oxygenated muriatic; by analogy from fulphureous and fulphuric, nitrous and nitric, Sec. Suppofing the ordinary muriatic acid to be an imperfecl acid, and the oxy-muriatic to be a perfeel acid, but not a fuper-faturation with oxygen. When it is mixed with ammoniac, decompofition with great effervefcence, takes place; no neutral fait is formed; but the hydrogen of the ammoniac, combining with the fu- perabundant oxygen of the acid, forms water, the nitrogen efcapes in the form of gas, and common muriatic acid is left. If the acid and the ammoniac are mixed in the ftate of gas, confiderable detonation and inflammation fucceed. Phofphorus and carbon immediately unite with its oxygen, and form phofphoric and carbonic acids. Phofphorus, charcoal, cinnabar, antimony, bifmuth, zinc, and feveral other combuftible bodies, reduced to powder, are fpontaneoufly inflamed when thrown into this acid, warmed and in a ftate of vapour. ■ Gren, 52 It removes the ftain of common ink, though it docs not affect printer's ink. It is therefore recommended for clean. ing old books and prints. Half an ounce of minium being added to three ounces of common muriatic acid, will ren- der it fit ;or this purpofe.. < Fabroni Giornale Litt. di Na- poli. It powerfully bleeches linen, cotton cloths, and paper j and in the proportion of twelve ounces to forty-eight pounds of fpirit of wine, it is exceedingly efficacious in bleaching raw filk, and even entire garments.——Journal de Phyfique, XLIII. MURIATES are neutral falts, formed by the muriatit acid, and certain bafes. Muriate of Pot-ash, the febrifuge Salt of Sylvius. It contains in ico grains, 29,68 acid, 63,47 alkali, and 6,8j water. It is found in fea-water, in old plaifter, and in ve- getable and animal fluids. It cryftallizes in cubes, which have a ftrong, bitter, difagreeable tafte. Muriate of Soda, Marine Salt, Common Salt, Rock Salt, Bay Salt, or Sal Gem, contains in 100 grains 43 acid, 46 alkali, and 11 water. It is found native, in mines, in many places, but particulaily in Poland and Hungary, Thefe mines appearing, from the fhells, madrepores, &c. which are found in them, to have been formed by the dry* ing up of vaft lakes. It is alfo obtained by extracting it from fea water, by evaporation, purification, &c. It is not decompofed by filica, and but flightly by clay. It howetei occafions clay to fufe readily, and is thus employed in gla* zing pottery: it affifts the fufion of glafs alfo. It has a pe- netrating pleafant tafte, decripitates on hot coals, and by great heat, is volatilized without decompofition. It cry-* ftallizes in cubes, or in hollow tetrahedrons, foluble in i,j their weight of cold water. The foda is advautageoully obtained from it by the addi- tion of nitric acid, and the oxides of lead. The foda is al- fo feparab'e by baryt, pot-afh, and particularly by the ve- getable acid combined with lead ; the muriatic acid uniting with the lead, and forming a muriate, whilft the foda com- bines with the vegetable acid, from which it may be after- wards freed by evaporation and calcination. Prouft has difcovered mercury in the muriatic acid, in the ftate of corrofive fublimate, arifing from mercury which i» naturally contained in fea fait.----Journal de Phyfique. Muriate of Ammoniac, or Sal Ammoniac, is found native in many parts, particulaily in the neighbourhood of volcanos. It is obtained artificially, by diftiilatioa from. i>5 the foot, formed by the combuftion of the excrements of a- nimals which feed on faline plants, ioo parts contain 52 acid, 40 ammoniac, and 8 water. It cryftallizes in qua- drangular prifms, with tetrahedral pyramids; or in rhombic or octahedral cryftals ; of a lharp, acid, urinous tafte, AW- ing a flight degree of ductility under the hammer. It dil- folves in three parts and a half of water, at 6o°. It is not decompofed by clay, nor entirely by magnefia : but is com- pletely decompofed by lime, and fixed alkalies, the ammo- niac being difengaged in the ftate of gas, leaving a muriate of lime or of alkali. If the lime or fixed alkali is pure, cauflic or pure ammoniac is obtained, but if the carbonate of lime or of alkali be employed, then a carbonate of am- moniac is the refult of the procefs. Muriate of Lime, Muriated Calx, Calcareous Marine Salt, or Glauber's fixed Sal ammoniac, is found in mineral waters, but particularly in the waters of the fea, to which it contributes to give their bitter tafte. It conftitutes the refidue of the diftillation of 3 parts of lime, 1 of water,. and 1 of muriate of ammoniac. It fpeedily deliquefces, and therefore, cryftallizes with difficulty, in hexahedral prifms, with hexahedral fummits. 100 parts of lime take up 86 of real marine acid. It is decompofed by baryt, and the alkalies. It fufes with a moderate heat, and becomea the Phofphorus of Homberg, which gives light when ftruck upon or fcratched. A very ftrong folution, being mixed with the concentrated fulphuric acid, a folid precipitate is formed, and the acid difengaged in vapours ; the two liquids appearing to be inftantly transformed into a folid. Like the nitrate of lime, this fait renders the flame of alcohol red. Muriate of Magnesia exifts in the mother water of falt-works, in fprings, and in the waters of the fea. It forms acicular, but deliquefcent cryftals, of an acrid and bitter tafte. 100 parts contain 34 of acid, 41 of magnefia, 25,of water. Muriate of Baryt does not feem to exift native. When obtained artificially, it forms in tabular cryftals, which do not fuffer any change in the air or fire, and have a naufeous- and burning tafte. Pure alkalies and earths have no effect on this fait. The fulphuric and fluoric acids decompofe it very readily ; hence this fait is highly ufeful to deteft the. prefence of thefe acids in any mixture. This fait produces the fame effeft on the flame of alcohol as the nitrate of baryti doe*, giving it a yellowifh white hue. Ei 54 Muriats of Alumine cryftallizes with difficulty, leav- ing generally, after evaporation, a faline aftiingent mafs, of a gummy confiftence. Muriate of Strontian forms hexahedral prifms with alternate broad and narrow furfaces, with trihedral pyramids. It gives to the flame of alcohol a bright red colour. Muriate of Glucine forms in fweet and very fmall cryftals. Muriate of Zirconia forms in indeterminate acicu- lar cryftals, deliquefcent, eafily decompofed by fire, and pof- fefling a fharp, auftere tafte. Muriate of Silica is obtained by the action of this acid on the filica in a ftate of divifion with alkali, it exifts only in a liquid and cold ftate, heat precipitating the filica, Fourcroy, 1800. Ammoniaco-magnesian Muriate is formed by a mixture of the folutions of the two muriates. It forms fmall, irregular polyhedra ; is foluble in feven parts of wa- ter, and contains muriate of magnefia 73, and of ammo- niac 27. Oxy-muriate of Pot-ash is formed by introducing the oxygenated muriatic gas into a folution of pot-afh; its C/yftals are flat hexahedral prifms, obliquely truncated at their ends, and of a filvery hue. They give a faint tafte, with a fenfation of coldnels in the mouth, and emit light by attrition. It appears to contain more oxygen, than an equal weight of oxygenated muriatic acid in water: hence the acid, combined in the muriate, is fuppofed to be fuper-oxygena- ted. It is faid to be decompofed by the action of light, parting with its oxygen, and becoming fimple muriate. This is, however, denied by Mr. YioyXz.—Manchefler Memoirs, vol. v. Heat feparates its oxygen from it, in the form of oxy- genous gas, 100 grains yielding 75 cubic inches of oxygen gas. On being brought into contaft with inflamed bodies, it detonates with more violence than nitre. When mixed with equal quantities of fublimed fulphur, it explodes, by mere trituration ; and fpontaneoufly, if kept in a bottle. ... 1 ■ >Nicholfon's Journal. A gra;n or two of phofpftorus being dropped in a folution of the oxy-muriate in nitric acid, a great number of vivid flafhes appear in the liquor. 5$ A little of this muriate being put into the fulphuric acid, violent cracklings or fmall explofions fucceed, and if a fmajl piece of phofphorus be alfo dropped in, a violent explofion takes place; the addition of heat will alfo occafion its ex- plofion. This muriate being rubbed with an equal quanti- ty of phofphorus, a violent explofion follows with a flafh of light. If mixed with charcoal, and fmartly ftruck with a hammer, flame, but not much no'rfe, fucceeds ; but with pit-coal, fparks, and fome fmall reports are produced t with fulphur a report and flame ; and with fulphuret of pot- afh, and of arfenic the fame effects follow, but in a higher decree. Detonations in-various degrees are occafioned by its being rubbed with loaf-fugar, oils, camphor, rofin, gum-arabic, indigo, aurum mufivum, Sec.—Manchefler Memoirs, vol. v. part i. The oxy-muriate of carbonated pot-afh increafes the blacknefs of ink, ufed in the proportion of i to 5 of the fulphates contained in the ink. The colours of logwood, weld, cochinelle, and archil, are improved by it, if no- heat be employed. Being blended with foap, the foap is improved in its qualities.——.4. J. Forfytb, Nicholfotis Journal, July, 1799. Being employed in the fabrication of gun-powder inftead of nitre, the effects produced by its ignition, are augmented to a four-fold degree ; and the mixture will explode by mere trituration. Oxy-muriate of Soda differs from that of pot-afh, in being more difpofed to effervefcence, and to folution in alcohol. Of the other oxy-muriates but little is known. Van Mons fays, he formed the oxy-muriate of ammoniac • but Gren afferts that fuch a combination cannot exift. Nitro-muriatic Acid, or Aqua Regia, is formed by diftillation of the nitric and muriatic acids in the propor- tion of two parts of the former, and one of the latter. Four ounces of fal-ammoniac diffolved gradually, in the cold, in one pound of nitric acid, forms an aqua regia. The mu- riatic acid, in thefe proceffes, attaches to itfelf a portion of the oxygen from the nitric acid, as well as a portion of ni- trous gas ; forming a mixture of muriatic acid thus oxyge- nated and of nitrous acid. The nitro-muriatic is of a yellow colour, and its fpecific gravity is lefs than that of either of the acids employed. It readiiy diffolves gold, which is not done by either of the acids of which it is compofed. It is employed by the dyer* for the folution of tin, which nitric acid corrodes, and oxi- dates without diffolving. 56 OF ACID OF BORAX. ACID OF BORAX, formerly called Homberg's Sedative Salt, has been found naturally formed in feveral parts, but it is generally found in combination with foda, forming borax, from which it is obtained by fublimation, or cryftallization. The nitric and muriatic acids may be employed for this pur- pofe ; but half its weight of fulphuric acid poured on bo- rax, yields the acid by fublimation, in a beautiful ftate. It is alfo obtained by cryftallization, by adding fulphuric acid to a folution of borax in hot water. The acid is depofited on the fides of the veffel, of a white, fcaly, glittering ap- pearance, as the mixture cools : it is alfo feparated by the vegetable acids. It yields a faline cool tafte, and reddens the blue vegetable infufions. It requires one pound of boiling water for the diffolution of 183 grains, but is dif- folved more eafily in alcohol ; the folution being of a beau- tiful green, and burning with a green flame. Expofed to the fiie, it becomes a vitriform and tranfparent fubftance, if dry ; but if moift, it fublimes, being mechanically raifed up with the aqueous vapours. But its fixity in fire greatly diftinguifhes it from the other mineral acids. Its acidifiable bafe has not yet been feparated. Borate of Soda, or Borax, is formed by the combi- nation of acid of borax and foda. The borax of commerce is a borate fuperfaturated with foda. It is found in a cry- ftallized ftate, at the bottom of certain fait lakes in a barren volcanic diftrift of the kingdom of Thibet, invefted in a greafy covering, and is called brute borax, tincall, or chry- focolla. It is alfo found in a purer ftate in the mines of Riquintipa, and of Efcapa. A ftill purer kind comes from China. It is beft purified by long boiling ; the cryftals this affords, being again purified by a fecond filtration and cryftallization. When purified, it is white and tranfparent,. with fomewhat of a greafy fracture. It has a pleafant acid tafte, renders the blue vegetable infufions green, and forms in hexahedral prifmatic cryftals, two fides of which exceed the others in breadth, terminated by three fided fummits. It requires twelve times its weight of cold water to diffolve it j but it is diffolved in fix times its weight^of boiling water. Expofed to a moderate heat, it melts with its water of cryftallization, and is reduced into white opake light mafs, when it is commonly called calcined borax. In a more 57 violent heat it is fufed into a tranfparent greenifh yellow glafs, foluble in water, and efflorefcing in the air. Baryt, magnefia, and lime, decompofe borax. It ferves as a flux to verifiable earths, it alfo vitrifies clay, but lefs complete- ly. It is employed in forming reducing fluxes ; it may alfo be ufed in re-producing the fufion of glafs ; and in foldering metals it is highly ufeful, cleanfing the furface of the metal, and aflifting the fufion of the folder. ■ Borate of Pot-ash, formed by the combination of the acid of borax with pot-afh, is obtained either by adding pot-afh to a folution of borate of foda, or by direftly com- bining the acid with the pot-afh. It cryftallizes in paral- lelopepidons. . Borate of Ammoniac forms in fmafl rnombonJal cryftals, eafily decompofed by fire. Borate of Magnesia is of very difficult fohrtion in water. It yields cryttalline grains by evaporation, and is decompofed by lime. Borate of Alumine is not very foluble, and melts in the fire into a glafs. Lime, magnefia, and the alkalies de- compofe it. Borate of Lime, or Boracite, has been found in the gypfum of Lnneburg, in cryftals whofe form appears to be a cube truncated all round on its corners and edges. It is infolubie in water, cuts glafs, and ftrikes fire with fteel. Borate of Baryt, and of Strontian, have not yet been fufficiently examined. With Silex in the dry way borax forms a vitreous fubftance by fufion : but does not unite with it in the hu- mid way. OF FLUORIC ACID. FLUORIC ACID is derived from the fpar, formed by this acid, and calcareous earth, and which, from its pro- perty of accelerating the fufion of other ftones, is termed FLUOR spar. It is thus obtained; the (lone is diftilled in a leaden retort, with its own weight of fulphuric acid, when a gas, termtd fluoric acid gas, is detached, which. forms the fluoric acid, on coming in contaft with water; the fulphuric acid, at the fame time, forming gypfum, by combining with the calcareous earth. Being diftilled.ia 58 glafs, it feizes the filiceous earth of the glafs, and volatiK. zing it with itfelf, depofits it as a iiliceous cruft on the fur- face of the water in the receiver. In fmell and tafte it re- fembles the muriatic acid. It does not aft on gold, or filver, but combines in prefer- ence with their oxides. From its power of diffolving filiceous earth, it is employed for the purpofe of etching on glafs. 6 The fluoric acid prefents an excellent means of detecting the prefence of lime, it taking it even from the fulphuric acid and immediately precipitating with it. Its radical is not yet known, but it Hppears not to be faturated with oxygen, Gren, therefore, thinks we have not had it in its perfefi or oxygenated ftate, and that it therefore deferves farther invefligation. Fluate of Pot-ash is a gelatinous fubftance, which readily diffolves in water, deliquefces in the atmofphere and is with difficulty chryftallized. It is decompounded by lime, the lime uniting with the acid, and forming rege- nerated fluor: it is decompofable alfo by the fulphuric acid. Fluate of Soda is not readily foluble in water. It forms fmall cubic or oblong tetrahedral cryftals, which de- crepitate like common fait, and are decompofable in the fame manner as the former. Fluate of Ammoniac fhoots into fmall columnar cryftals, which have a bitter tafte, and are deliquefcent. It is perfectly fublimable by heat, and forms, when dry, a fubftance refembling flint. Fluate of Lime, or Fluor Spar, is of a compact fpar- ry texture, of various colours, hard and brittle. Sp. gr. 3,09 to 3,19, nearly infolubie in water, and becomes phofphorefcent in a moderate heat. It promotes the fufion of clay, and other earthy fubftances, but is not very fufible itfelf. Its general form of cryftallization is that of the cube, and of its more fimple modifications. It contains acid 16, lime 57, water 27. Scheele. The amorphous and earthy has, ac- cording to Pelletier, acid 28,5, lime 21, water 1, filex 31, alumine 15,5, iron 1, muriatic acid 1, phofphoric acid 1. Fluate of Argill has been found in Greenland. But the combinations of this acid with the other earths have not been much attended to. Thefe fluates aft on filica, and by diffolving it, become filiceous fluates. As an examination of the different fubflances from which the *e:dsare obtained, cannot but facilitate the knowledge of S9 the nature of the acids themfelves, the remaining acids will be treated of, when the analyjis of the refpeclive fubftances from which they are produced, are defcribed. This is the more neceffary, flnce, as feveral of thefe acids appear to owe their exiftence to certain proceffes of animal and vegetable life; thefe can alfo be taken into confideration at the fame time. METALLIC SUBSTANCES. THESE are diftinguifhed by their abColute opacity, great degree of gravity, and peculiar brilliancy ; to which may- be added their dutlility, which property, however, is not perhaps poffeffed by all metals. They are concealed in the earth, and from ores, which exifting in crevices of rocks, are called veins, and are dif- tinguifhed into level, or info inclined, direcl, or oblique, according to the angle they make with the horizon. The part of the rock refting on the vein, is termed, the roof; and that on which the vein refts, the bed of the vein. When found in fpherical parts, or maffes, they are called bellies, or ftockworks. Metals appear to be fimple fubftances. They are af- fayed, and their fpecies afcertained, by the Docimafiic Ail, or DOCIMASIA. The metallic part is firft cleared, as much as poflible, from the foreign, or ftony fubftances, with which it is blended, and which is called the gangue, by firft, reducing the ore to powder, in which ftate it is called flich, and then by wafhing. It is then torrefied to diffipate the fulphur and arfenic ; and Jaftly, fufed by the addition of fome flux, containing the eoally principle, to difengage the oxygen, with which the metal has been impregnated, during the previous calcination, or torrefaftion. They are found, i. In the form of a native metal. 2. In the form of calx or oxides. 3. Combined with arfenic, or ful- phur. When nature has bellowed on them their proper metallic appearance, or they are only alloyed with other metals, or femi-metals, they are faid to be native. When combined, as they commonly are in mines, with fome un- metallic fubftance, they are faid to be mineralized; the fubftance that fets them in that ftate, is called a mineralizer 5 and the compound of both, an ore ; which term is applica- ble, when ftones, or earths, contain metallic fubftances, t)U whether native or mineralized, in a notable proportion. They are commonly mineralized by oxygen, in its concrete ftate, to which is often fuper-added, the carbonic acid. Next to thefe, fulphur, and arfenic, in its oxidated ftate, occur; thefe laft generally communicate a metallic luftre. The fulphuric, muriatic, phofphoric, arfenical, and mo. lybdenic acids, are lefs commonly met with. They fufe at a certain degree of heat, and obtain a con- vex furface ; and if fuffered to cool flowly, they exhibit cryftallizations of confiderable regularity If continued in a ftate of fufion, they lofe their brilliancy, and become an opake powder, or metallic oxide, or calx; acquiring weight, and abforbing a certain portion of oxygen, during the tranfition. If this be abforbed to faturation, the oxide may be called perfecl, if not, imperfecl. If urged by a ftror.ger heat, all the oxides, except of quickfilver, are converted into a vitriform fubftance, or metallic glass, Thefe mixed with other glaffes form glafs pafies, and artificial gems, pigments for enamel and porcelain, enamel itfelf and the finer glazings. That metals are calcined, or rather oxidated, in confe. quence of their abforbing oxygen, is proved, by this pro. cefs taking place only when oxygen is prefent; and by their giving it out, in exaftly the fame quantity and proportion, on their reduftion, or return to the metallic ftate. They undergo this procefs of calcination, or oxidation, alfo from the action of humidity : the water is decompofed; its hy- drogen being diflipated, whilft its oxygen combines with the metal. The bafer metals have their furfaces tarnifhed by expofure to the air, being afted on by the carbonic acid and oxygen, the tarnifh or ruft being a carbonated oxide of the metal. They are all foluble in acids, and precipi- table therefrom by alkalies; or, platina excepted, by Pruflian alkali. Acids are decompofed, during their com- bination with metals, their oxygen combining with the metal, and forming a metallic oxide : this is either diffol- ved, and forms a metallic fait, or the metal is only corroded and the oxide precipitated. Metals may be diffolved by means of alkaline fulphurets, and the metal and the fulphur may be precipitated together. This precipitate is a combination of the metal with the ba- fis of fulphurated hydrogen gas, and is called a METALLIC hydro-sulphuret. They may alfo be made to enter into combination with ammoniac, when fubftances are form- ed which are termed ammoniurets. If calcined, and not too volatile, they communicate a tinge to borax and microfcomic fait, after fufion, or rendea' 61 them opake. When perfeftly fufed, they are, for the moft part, mifcible, or combinable with each other; but, except- ing iron, refule to mix with their own oxides, or with moft other unmetallic fubftances. They however unite with fulphur, phofphorus, charcoal, ammoniac, hydrogen, and alkaline Ailphurets. Thus we have metallic sulphurets, phosphurets, carburets, AMMONIURETS, HYDRURETS, and HYDRO-SULPHUR- ETS. The names of fuch metallic fubftances as are at prefent known, are, i. Platma. 2. Gold. 3. Silver. 4. Quickfilver. 5. Copper. 6. Iron. 7. Lead. 8. Tin. 9. Zinc. 10. An- timony. 11. Bifmuth. 12. Cobalt. 13. Nickel. 14. Manganefe. 15. Uranite. 16. Sylvanite. 17. Titanite. 18. Chrome. 19. Arfenic. 20. Molybdenite. 21.Tun.g- ftenite. The three firft, undergoing no oxidation in our furnaces, are called perfetl or noble metals, and the others imperfecl, or bafe. The oxides of the former may, however, be ob- tained by other means ; and differ from thofe of the bafer metals in this, that they, as well as that of quickfilver, are reduced to a metallic ftate, by mere heat; whereas thofe of the bafer metals require the addition of a combuftible mat- ter. Thofe which are not at all, or flightly maleable, have been termed femi-metals. The four laft are capable of fuch complete oxidation as to be converted into real acids, and are therefore called acidifiable metals. Pyrites, or Marcafites, are metallic sulphurets, which are formed by the union of metals with fulphur. The moft common of thefe are the sulphurets of iron. PLATINA comes to us in a granular ftate from Peru. It has no known ore, but is found in a metallic ftate, only among alluvial gold ores. Its colour is between the tin and filler white. Sp. or. 20,6 to 23 : being the moft ponderous of all known bodies. It is confiderably malleable, and duftile; but harder than gold. It is not affefted by the action of the air, nor by the heat of an ordinary furnace ; but yields to the heat pro- duced by powerful burning glafles, and to that excited by ignited oxygen gas. It is often mixed with quickfilver, and gold, and is inti- mately combined with iron, and therefore magnetic. The F mercury may be driven from it by heat, and the iron may be feparated from it by diffolving it in eight times its weight of nitro-rnuriatic acid, and either precipitating the iron, by Pruflian alkali, or the Platina itfelf by muriate of ammoni- ac. This precipitation of platina, by the muriate of am- moniac, affords a fimple method of afcertaining the mixture of this metal, with gold, fince the muriate of ammoniac has no vifible effeft on the folution of gold. It is foluble in the nitro-muriatic, and the oxy-muriatic acid; the faturated folution being of a dark-red colour. It is precipitable from this folution, by pot-afh, and muriate of ammoniac; lefs freely by foda, not vifibly by the Pruffian alkali, and not at all, by a dilute folution of fulphate of iron: thefe properties diftinguifh it from gold. Berthollet iound it in a great rreafure acidified, whenjin folution, which accounts for fome of its fingular properties. The folution depofits fmall irregular fawn-coloured cryftals, the muri- ate of platina ; and if concentrated, it yields larger cryftals, fometimes of an oftahedral form.-----Bergman. It amalgamates, though with difficulty and very fparing. ly, with quickfilver, and is capable of being alloyed with moft of the known metals. With bifmuth it unites eafily, and yields a mafs of little duftility: with antimony, its fufion is facilitated, but its weight and duftility are leflened -. and by zinc it is rendered more fufible, the alloy being very hard. It unites eafily with tin, is very fufible, and unlefs the tin is in large pro- portion, the alloy is very brittle. It unites very well with lead. One ounce of platina be- ing cupelled with 20 ounces of lead, the platina gains the power of being forged and foldered completely, without the afliftance of any other metal.——Bourne. It will not unite with forged iron, but melted with crude iron, the alloy is fo hard, the file will not touch it; it is duftile in the cold, but breaks fhort when hot.----Lewis. With copper, the alloy is duftile : when the copper is in the proportion of three or four to one, it takes a fine polifh, and does not tarnifh in the fpace often years. With fiher, the alloy is hard, without duftil ty, -and tarnifhes. But with gold, it can only be alloyed by the moft violent heat; the colour of the gold is prodigioufly altered, and the alloy poffeffes -confiderahle ductility. Platina free from iron, being fufed with phofphorus, by long continued heat, is obtained in a concrete porous foriBi and may be formed into a folid mafs, under the hammer, facing a phqsphurft of platina. 63 GOLD.—Its colour is orange red, or reddifh yellow. Sp. gr. 19,3. melts at 320. Wedgwood. It may be volatilized and calcined, in high and long continued heats. It is the moft perfcft, duftile, tenacious, and unchangeable of all the known metals. Not being combinable with oxygen, fulphur, &c. in low heats, it can never be found, ftriftly fpeaking, mineralized. It is found in compact maffes, or interfperfed in various mod^s. Its form of cryftallization is generally the alumini- form octahedron, "with its modifications. It is more extenfively diffufed, though in exceeding fmall quantit es, than any other metal, except iron- It has been obtained from vegetables, by Becher.—From rotted manure, garden-mould, and uncultivated earth, by Monfieur Sage. —From afhes, by Berthollet.----Gold may therefore be faid to exift in vegetables. It is not attacked by the fulphuric acid, and is very {light- ly afted on by the nitric acid; but is attacked with moft energy by the nitro-muriatic acid, or aqua regia, as it is called, and the oxy-muriatic acid, which are the true folvents of gold. This folution yields yellow cryftals, refembling topazes, in truncated oftahedra, thefe cryftals being a true muriate of gold. It tinges animal fubftances purple, and by difrillation, yields a red liquor, called by the adepts, the red lion. An oxide of gold is precipitated from this folution, in a. yellow powder, nearly in a metallic ftate, by lime, magnefia, and by alkalies; the precipitate being folu- ble in the fulphuric, nitric, and muriatic acids. When precipitated by ammoniac from the yellow folution, it is called fulminating gold, it detonating when gen- tly heated. Fulminating gold has been proved to be a mix- ture of ammoniac, and oxide of gold ; the oxygen of the latter, and the hydrogen of the alkali, taking fire by fimple heat, detonate; and the gold is reftored to its metallic ftate. It does not unite with nitrogen, hydrogen, carbon, nor fulphur; nor does it aft on water or the metallic oxides_____ Fourcroy, 1800. It is precipitated from its folution by feveral metals, fuch as lead, iron, filver, copper, bifmuth, mercury, zinc, and tin. This laft precipitates it in a powder, much ufed in porcelain manufailories, termed, the purple powder of cassius. It may be inftantly precipitated, and revivi- 1! r Yc e,'r' the g°ld ^mediately forming a ftratum at the furface of the now colourlefs liquor. 64 Gold is alfo diffolved completely by the fulphurets of al- kalies, merely by fufing equal parts of fulphur and pot-afh, with one eighth of the total weight of gold in leaves; it may then be poured out, pulverifed, and diffolved in hot water, being an hydro-sulphuret of gold. Stahl affirms, that by this procefs Mofes diffolved the golden calf. It may be obtained pure, by precipitation, with a dilute fo- lution of fulphate of iron, from a folution of gold, in ni- tro-muriatic acid. , It unites with moft of the other metals ; and is rendered brittle by arfenic, as well as by bifmuth, nickel, and anti- mo?iy, and unites well with tin, and lead, but lofes all its duftility. Mr. Alchorne expreffes an opinion, that the addition of a very fmall quantity cf tin to fine gold, is not fo injurious as workmen have imagined.----Phil. Tranf. But after repeating Mr. Alchorne's experiments, M. Tillet is convinced, that the alloy of a very fmall quantity of tin with gold h injurious, the mixture poffefling both hardnefs and rigidity.- Mem. de VAcademie, 1790. With iro/:, it forms a very hard and ufeful alloy ; and by copper, it is made more fufible, and rendered of a redder colour. This alloy is employed for coin, toys, gold-plate, Sec. It is rendered very pale by filver. This alloy forms the green gold of goldfmiths. Gold; from its extreme duftility, is drawn into very fine wire, for embroidery, and into leaves of the greateft tenuity, one grain bein^ capable of exteniion over 56^ fquare inches. Gold is employed for the purpofe of gilding the furfa- ces of copper, brafs, and filver, in the following different proceffes. ift. Hot gilding, for the Or Moulu; the metal to be gilt is firft wafhed with a folution of nitrate of mercu- ry, 01 amalgamating water; this-gives a mercurial furface, to which an amalgam of gold and mercury is applied ; from which the mercury is driven off by heat. The colour is then heightened, by burning on it a covering of gilder) wax, formed of wax, verdigris, and blue vitriol; it is then polifhed, and brightened by a boiling folution of common fait and cream of tartar. 2nd. Grecian gilding of filver Is performed by a folution of gold in nitric acid, to which fal-alembroth (a- triple fait formed by fal ammoniac and conofive fublimate) has been added. This folution of geld, evaporated to the confidence of oil, is applied to the fiver, which it blackens, but which appears gilded after being heated. 3d. Cold gilding is perfoimed by rubbing the me- 65 tal with the afhes of a linen rag which has been impregnated with a folution of gold. 4th Wet gilding, by merely dip- ping the work into a folution of gold. ■ Gren. SILVER is of a pure white. Sp. gr. before malleation, 10,474 ; after, 10,510. It is malleable, duftile, and lamin- able, in a high degree, though inferior to gold ; and is net changed by the contact of air. A wire i-ioth of an inch, will fupport 270 pounds. It is fufible at 280, or rather it remains in fufion at that degree, for it requires a higher degree to bring it into fufion.* If by means of folution of borax, a fmall bit of leaf filver, be ftuck to the t©p of a fmall glafs cylinder, and melted in- to it, it will give it a golden tinge.----Bergman. By long expofure to violent heat, it has been converted into a glafs of an olive green colour. In the focus of a burning glafs, it yields a white pulverulent matter »^but there appears to exift but little affinity between it and oxy- gen. Gold and filver readily combine, and form an ufeful al- loy. Having different folvents they may be PARTED three different ways, ift. By diffolving the filver of the alloy by nitric acid; butas for this procefs it is neceffary firft to take care that the gold is not more than a quarter part of the mafs, the procefs is called quartation. 2dly. By cementation, or parting by concentration, the alloy being placed in a cruci- ble, in firata with the cementing powder. The ingredients of this powder muft be fuch that by an intenfe heat it will yield either pure nitric or pure muriatic acid vapours, as thefe will lay hold of the filver and leave the gold untouch- ed- 3diy- Bv dry parting, which is by fufion with fulphur, the filver quitting the gold to unite with the fulphur. When alloyed with copper, it is rendered hard, and fit for filverfmiths work, and for coinage. The alloy for the Bntifh coinage, is 11 ounces, 2 pennyweights fine. With fulphuric acid, if concentrated, fulphureous gas is difengaged, and the filver is converted into a true oxide of silver, mixed with a fmall quantity of sulphate of F 2 the degrees of heat requisite >ces. 66 silver, in-fmall needles, or in plates formed of thefe nee- dles, united length-ways. It is diffolved in nitric acid with rapidity, if water be ad- ded to the acid, and much nitrous gas is difengaged. The folution is at firft, blue; but this colour difappears when the filver is pure, and degenerates into a green, if it be al- loyed with copper. Nitric acid will diffolve more than half its weight of filver, the folution letting fall cryftals in hex- agonal, triangular, or fquare plates, which are called ni- trate of silver, or lunar cryftals, lunar nitre, Sec. This melted with a gentle heat, and poured into moulds as loon as fufed, forms the lapis infemails, or lunar caufiic. By fixed alkalies it is precipitated from its folution, whitej by ammoniac, grey ; and by lime-water, olive-green. It may be precipitated from a dilute folution, by a plate of copper. The filver adheres like mofs to the copper, and the liquid acquires a blue tinge from the copper, which is diffolved in the room of the filver. It is likewife precipita- ted by mercury, with which it will alfo amalgamate. Thefe cr^'als, being articulated into each other, give them the form of a vegetation, known by the name of the TREE of Diana, Arbor Diana, Sec. Nitrated filver, being precipitated from its folution, fepa- rated from the fluid, expofed three days to the air and light, and mixed with liquid ammoniac ; becomes, when dry, fulminating silver. This exceeds in power, gun powder, and even fulminating gold. Once obtained, it can no longer be touched without a violent detonation, no more than one grain being fufficient to give rife to a dangerous fulmination : after this fulmination, the fil«er is found re- duced or revivified, its oxygen having combined'with the hydrogen of the ammoniac, by which water, in the ftate of vapour is produced. This water, inftantly vaporifed, and poffeffing all the elafticity, and expanfive force of that ftate, is the principal caufe of the phenomenon; in which the ni- trogen of the ammoniac, with its whole expanfibility, bears a part. It is readily combined with the muriatic acid, by adding this acid to a folution of filver in the nitric acid, the mu- riate of silver being precipitated ; this muriate is very fufible, running into a grey and tranfparent fubftance, like horn, and is then called luna cornea, or horn filver J this being fufed with four parts of pot-afh, the filver is found in the pureft ftate, under a ftratum of fulphate of pot-afh, and the remaining alkali. It may likewife be decompound- ed by feveral other metals. C7 Profeffor Hildebrant fays, I have frequently re-diffolved, in pure nitrous acid, the filver which I obtained from horn filver, and always found a fmall quantity of black-powder remaining at the boitom, which feemed to have the proper- ties of gold. To appearance, part of the filver is converted to gold ; but the Profeffor, accounts for it, from the filver, though called pure, containing the gold thus found. The muriate of filver, expofed to the light of the fun, foon becomes brown, oxygen gas being difengaged. Nitrated filver, and moft of the folutions of metals, thus emit their oxygen, and become coloured. Carbonate of Silver may be obtained, by precipi- tating it by the carbonate of alkali. Sulphur unites with it; this SULPHURET of SILVER is known as vitreous filver ore. An alkaline sulphuret of silver maybe obtain- ed by fufion with alkaline fulphuret, and from the folution of this an hydro-sulphuret of silver may be obtain- ed by precipitation by an acid. Phosphuret of silver may alfo be obtained by the fufion of filver and phofphorus. Mr. Keir difcovered that a mixture of the vitriolic and nitrous acids, in a concentrated ftate, has a peculiar faculty of diffolving filver copioufly : and at the fame time, oxida- ting tin, mercury, and nickel ; diffolving, however, a fmall quantity of the latter, and having little or no aftion on o- ther metals. By dilution, the mixture becomes lefs capa- ble of diffolving filver, aud more capable of-acting on other metals. Phil. Tranf. 1790. QUICKSILVER is of the colour and luftre of polifhed filver. Sp. gr. 13,568. It is as indeftruftible by fire as gold and filver, and has therefore been arranged among the perfeft metals. It is volatile in heat, and boils in the fame manner, as other liquids when heated. It remains liquid between 6ooe above, and 720 below the freezing poii.t. When congealed by cold, it acquires mal- leability. Mr. Walker fays, that quickfilver may be frozen by a mixture of fnow and nitrous acid, each being at -f. 70*. By ground ice, and nitrous acid, at + io°. To make it perfeftly folid and hard, a mixture of diluted fulphuric a- cid and nitrous acid fhould be ufed with the powdered ice, but then the materials fhould not be lefs than__io« before mixing.— Phil. Tranf. 1795. 6S Mr. Pepys congealed fifty-fix pounds of mercury into a folid mafs, by mixtures of muriate of ljme, and uncompreffed fnow, in equal weights. The mafs was broken by accident, the larger pieces were kept for fome minutes befote fufion took place, whilft others were twifted and bent into various forms.—-Philof. Mag. Feb. 1799. It is but little affefted by the air, except by long agitation in it, when it forms a black, but imperfecl, oxide, for- merly called JEthiops mercurii per fe, containing 0,5 or 6 oxygen ; but when afted on by heat at the fame time, it gra- dually lofes its fluidity, and at the end of feveral months, forms a red, and perfecl oxide, called Precipitate per fe, or calcined mercury, containing 0,14 to 0,16 oxygen.—This oxide gives out its oxygen, by fimple heat, one ounce afford- ing a pint, and the mercury refuming its metallic form. Expofed to heat, in clofe veffels, the oxide fublimes in beau- tiful red cryftals. Mercury does not appear to be at all changed, or deprived of any part of its weight, by the aftion of water. The fulphuric acid afts or. mercury, Only if affifted by heat, firft rendering it an oxide, and then diffolving the oxide. Cold water being added, a white oxide falls, and hot water being poured on it, it becomes a YELLOW, imperfecl, oxidb, called Turbitb mineral; the water holding in folution a sul- phate of mercury, cryftallizable in fmall, foft, andde- liquefcent needles. The fulphates may exift in three differ- ent ftates; 1 ft. With excefs of acid. 2d. Neutral. 3d. With excefs of oxide. The nitric acid diffolves mercury even without heat, ni- trous gas being dfengaged ; one part of the acid oxidatingthe metal, whilft the other diffolves it, as it is oxidated. With cold dilute acid, the oxidation is but imperfeft, but with heat and concentrated acid, it is complete. The nitric acid becomes loaded with an excefs of mercu- rial oxide, which it lets fall on dilution with water, and yields cryftals, in the form of flat and acute needles, ftria- ted lengthways. If the folution be made in the cold, and left to fpontaneous evaporation, the cryftals are tetrahedral prifms, truncated near their bafe, and having the angles, re- fulting from the junction at the bafes of their pyramids, like- wife truncated ; if this fame folution be evaporated, long and ^cute blades are obtained, ftriated obliquely acrofs. The Nitrate of Mercury is corrofive; when very dry, it detonates upon coals, and emits a brilliant white flame. Fufed in a crucible, or better in a retort, it yields oxygen or nitrogen gafes, the remaining oxide becoming 69 yellow, and at length a lively red, being the red precipitate, and if frefh nitric acid be diftilled from it three or four times, the precipitate is in fmall cryftals of a very fuperb red co- lour. The folution of mercurial nitrate forms mercurial water. It is of ufe to afcertain the prefence of fulphuric and muriatic falts in mineral waters. ioo grains of quickfilver diffolved with heat in a meafured ounce and half of nitric acid of 1,3. fp. gr. being poured cold upon two meafured ounces of alcohol of about ,849, and a moderate heat applied, a powder precipitates, which is to be immediately wafhed on a filter, and dried with a heat little exceeding that of a water bath. This powder takes fire at 360 Fahr. it explodes by friftion, by flint and fteel, and by being thrown into concentrated fulphuric acid. It is equally inflammable under the exhaufted receiver as fur- rounded by air, and it detonates loudly both by the blow of a hammer, and by a ftrong eleftrical fhock----Howard. Phil. Tranf. for 1800. _ From the folution in the nitric acid, the mercury is preci- pitated in the ftate of oxide, of different colours, by the a- cids, alkalies, earths, and fome of the metals. Thofe by the carbonate of ammoniac and lime-water, as well as that of the muriate of mercury by lime-water, fulminate when mixed with a fmall quantity of fublimed fulphur, and ex- pofed to heat, leaving a fmall quantity of a bluifh powder, which is a fulphuret of mercury. The muriatic acid does not fenfibly aft on mercury, ex- cept by long digeftion, when it oxidates a part, which ox- ide it diffolves. It completely diffolves the mercurial oxides, and when thefe, being charged with a fmall quantity of oxy- gen, are nearly in the metallic ftate, the muriate of mer- cury is formed. When, on the contrary, the oxide is fa- turated with oxygen, the oxy-muriate of mercury, or corrofive fublimate of mercury, is formed. This may be obtained either in the dry way, by fublimation from equal parts of nitrate Of mercury, or any oxide of mercury, de- cripitated muriate of foda, and fulphate of iron calcined to whitenefs, or from equal parts of fulphate of mercury, and decrepitated muriate of foda. In the humid way it may be obtained by diffolving mercury in the oxygenated muriatic acid, concentration producing very fine corrofive fublimate. This fait, placed on hot coals, diflipates in fumes ; and in proper veffels, riles in flattened prifmatic cryftals. Added to lime-water, it forms phagedenic water, a yellow preci- pitate falling; fixed alkali precipitates an orange coloured oxide ; and volatile alkali, a white powder, which become! brown in a fhort time, 70 To obtain the mild muriate of mercury, mercuriut dulcis, or calomel, equal parts of quickfilver, and of oxy- genated muriate, are completely blended by trituration, and this mixture expofed to fublimation, the reguline mercury becomes oxidated at the exper.ce of the oxygen of the oxide and yields the mercurius dulcis, which is infipid, infolubie m water, and if flowly fublimed, forms in cryftals of the form of tetrahedral prifms, terminated by tetrahedral pyra- mids. Mr. Baume remarks, that if lefs mercury be added a proportional quantity of mercurius dulcis only fublimes| and the reft rifes in the form of corrofive fublimate ; and if too much mercury be added, the excefs remains in the form of running mercury ; there being no intermediate ftate be- tween mercurius dulcis and corrofive fublimate. By repeat- ed diftillations, fuch a decompofition takes place, as produ- ces corrofive fublimate; the common method of frequent diftillations is therefore abfurd. To be certain that the mercurius dulcis holds no corrofive fublimate, it fhould be warned with tepid water. Mercurius dulcis may alfo be made by fubliming the white precipitate, made by decora- poling mercurial water by a folution of the muriate of foda. Borax added to mercurial water, a yellow precipitate falls, being a combination of the acid of borax and mercury : this fait forms brilliant cryftals by evaporation, the borate of mercury. It is in this manner by double attraftion, that this phofphoric, fluoric, and carbonic acids are made to unite with mercury. Corrofive fublimate is decompounded by different metals. An amalgam of tin and mercmy being flowly diftilled, a brown liquor is obtained, wheh, in contaft with atmo- fpheric air, emits white fumes for a confiderable time. This is termed fuming spirit of libavius ; it is a true oxygenated muriate of tin, formed in confequence of the oxygenated muriatic acid quitting the mercury and uniting to tin. Mercury long triturated and digefted with moiftened muriate oj ammoniac, forms an ammoniaco-mercurial MURIATF. The acetic acid diffolves the oxides of mercury, and af- fords wh:te fobated cryftals, the ACETATE of MERCURY. Mercury precipitated from the folution of the acetate of mercury, combines with the acidulous turtrite of pot-afh, and forms the vegeto-mercurial water of Preffavin. The acetate of mercury is the bafis of Keyfer's Pills Mercury mixed with fulphur, forms the red sulphu- ret, or the black sulphurated oxide, called alfo cinnabar and the athiops. 71 Four ounces of fulphur may be triturated with twelve ounces of fublimed fulphur, or four ounces of fulphur may be fufed in a crucible, and one ounce of mercury extin- guifhed in it, or the fulphur of pot-afh may be added to mercurial water. By all thefe means the black fulphurated oxide of mercury, or mineral aethiops, is formed. By fubliming thefe aethiops, the red fulphuret of mercury is obtained, called cinnabar. The Count Apollos de Mouffin Pouffchin prepared a beautiful cinnabar by triturating mercury, and flowers of fulphur, with a folution of cauftic vegetable alkali, keeping it at a proper temperature, and afterwards wafhing it repeatedly by boiling water, which carries off a fmall portion of sethiop's not fur-compofed.——Nicholfon's Jour- nal. As quickfilver precipitates filver but not copper from the nitric acid, it furnifhes an eafy mode of feparating filver from copper. Mercury amalgamates with moft other metals : on this property is founded the art of gilding. Mercury is alfo employed in painting, in forming mirrors, philofophical inftruments, Sec. COPPER is of a muddy red, with a fhade of yellow, malleable, flexible, and duftile, though inferior in thefe refpefts to filver. Sp. gr. 7,780 to 8,584. A wire i-ioth of an inch, will fupport 29.9! pounds. It melts at 270 Wedgwood. Expofed to the fire, it becomes blue, yellow, and at laft, violet. When in contaft with the coals, it gives a greeni/h blue tinge to the flame, and if kept long in fufion, part is volatilized. Heated in contact with air, it burns at its furface, and becomes changed into an imperfecl blackifh red oxide, which by a more violent heat, is converted into a brown glafs, or more perfea oxide. If melted and cooled flowly, it forms, according to Mongez, in quadri- lateral pyramids. It has no action on water, yields oxygen to many of tht metals; but takes it from mercury -And filver. -----Fourcroy, 1800. It combines readily with.fulphur, forming a very fufible mafs, termed sulphuret of copper. It alfo unites readily with phofphorus, forming a grey, brilliant phos- PHURET of COPPER. 72 It is afted on by the fulphuric acid, only when concen. trated, and very hot. It is then oxided by it, and affords blue oblong rhomboidal cryftals, being the sulphate of COPPER, blue vitriol, cyprian vitriol, blue copper, &c. compofed of oxide 0,32, acid 0,33, water 0,35. Lime and magnefia precipitate the copper of a bluifh white, as well as ammoniac ; but the precipitate from this, is diffolved at the inftant it is formed, and the refult is a beautiful blue liquor, called aqua celeflis. It is attacked by diluted nitric acid with effervefcence, abundance of nitrous gas being emitted. A blue folution is thus obtained, yielding cryftals cf nitrate of cop- PER, in long parallelograms, or rhomboidal cryftals. It is not diffolved by the muriatic acid, unlefs boiling and concentrated. The folution is green, and affords cubic cryftals, the muriate of copper, of a grafs green. Am- moniac does not diffolve the oxide of this muriate with the fame facility as that of other cupreous falts. When afted on by the acetous acid, it is corroded, and yields the fubftance known by the name of verdegris. Be- ing combined with oxygen, it becomes more readily foluble in vinegar. The oxide of copper diffolved in vinegar, forms the acetite of copper, diftilled verdegris, or cryftals of Venus. The phofphate, carbonate borate, &c, of copper are but little known. The blue folutions of copper, indicate the lefs, and the green, the greater degree of oxygenation.----Morveau. The fixed alkalies, and even many neutral falts aft on it, and it is faid, moft powerfully in the cold, and when expo- fed to the atmofphere. It is alfo readily afted on by rancid fats or oils. It is precipitated from its folutions, in its metallic form, by a clean plate of iron, the iron appearing to be converted into copper. The copper thus obtained, is known by the name of copper of cementation. It unites with the earths, only by vitrification. It mixes with moft of the metals and femi-metals, form- ins:, 1. With arfenic, or zinc, the white tombac j. With bifnuth, an alloy of a reddifh white colour, with cu- bic facets. 3. With antimony, a violet coloured alloy. 4. With zinc, by fufion, the similor, or manheim gold; or by cementation with calaminaris, brass. 5. In a folu- tion of quickfilver, it acquires a white furface from the pre- cipitation of the quickfilver. 6. It eafily unites with tin ; on this depends the art of tinning. Fufed with tin it forms 73 bronze, or bell metal. (Dr. Pearfon having exami- ned fome ancient metallic arms and utenfils, was able to afcertain that they confifted of copper and tin, in the pro- portion of from fix to twelve parts of copper to one of tin ; according to the ufe for which they were intended.) 7. With iron it contrafts very little union, 8. Alloyed with filver, it is rendered more fufible; thefe two metals are combined to form folder. 9. Added to gold, the gold is hardened, and its colour heightened. It precipitates filver from its folution in the nitric acid. This method is ufed to feparate the filver after the operation of parting. Copper filings being added to a cauftic fpirit of ammoniac, no folution takes place, except air be admitted; and if this be only admitted for a fhort time, though the folution takes place, it remains colourlefs ; but if air be admitted, it becomes blue at the furface, and then through the whole folution. If it has not been too long expofed, and frefh fi- lings be added, and the bottle clofed, it will lofe its colour, and only regain it by admiffion of air.----Gren. It is employed for various domeftic ufes. Its oxide is employed to colour glafs of a beautiful green. IRON, when frefh broken, is of a pale, fomewhat bluifk grey. Sp. gr. of caft iron, from 7,2 to 7,6: of bar iron, from 7,6 to 7,8; of fleel, from 7,78 to 7,84. It is the moft generally diffufed metal in nature : almoft every mine- ral fubftance deriving a colour from it, from the blue to the deepeft red. Animal fubftances contain it, and it exifts in the vegetable kingdom; even in vegetables fupported mere y by air and water. It requires for its fufion a heat equal to 1300 Wedgwood. rnmh,S(?bCdient t0,?. magnCt' is the °n,y metal caPable of conftantirr °\C0li.1J0n with qnartz, and the only metal It is diffl7 U^r efXrftine in the fluids of organized bodies. It is difficult of fufion, but may be hammered with heat into any form. When flowly cooled, it cryftallizes in^o oxtdaetd5\alm°ft alw3yS imP,3nted °"e in *' otne" t is oxidated by mere expofure to the air: abforbin? alfo thf TErD0OXianld 1thC at'"°fphere' a"d ^ni^RBOHA? fom, 1 a r IRr°"'. °n bein§ heated & a furnace for ofTlack felt. "rfaCe " °Xldated' and f£Parates in the f°™ This oxide is ftill drafted by the magnet, and contains from o,zo to 0,27 oxygen----Fourcroy, 1800. G 74 This oxide of iron, when moft.degraded, and of a redd«'fc brown colour, is the brown oxide of iron, formerly called the aftringent faffron of Mars. It contains 0,40 to 0,49 oxygen.-----Fourcroy, 1800. The colour varies with the degree of oxidation, becoming yellow and even red ; and is reduced to a black powder, by heating it with coally matters. Iron in filings, being conftantly agitated in water, a .black powder is depofited, being a perf&cl black oxide of iron, alfo called the martial athiops of Lemery. The oxidation is effefted by the air contained in the water ; but more efpecially by the decompofition of the water itfelf, hy. drogengas being developed during the procefs. With heat .this procefs is rapidly performed, and much hydrogen gas is feparated. After oxidation it is lefs attractable by the mag. net and lefs fokible in nitiic acid : poflefling thefe proper- ties, inverfely, as to the quantity of oxygen it contains. It is oxided in a flight proportion, by being digefted in a folu- tion of the fixed, or ^volatile alkalies, falling down in the form of an aethiops. It alfo deprives moft of the other me- tallic oxides of their oxygen, and burns with a flamewhen heated with red oxide of mercury. An iron wire, heated red-hot, being plunged in pure oxygen gas, burns and deflagrates with wonderful bril- liancy. . Iron, when fufed, may be call into fuitable moulds, in •which ftate it is called caft iron. If inftead of this it he ftirred when in fufion, and then carried to the forge ham- aner, and hammered into bars, it affumes a fibrous texture, and becomes more duftile: in this ftate it is called bar, « forged iron. If placed in contaft with coally fubftances, and foftened to fuch a degree that thefe may penetrate into its' texiure, a fubftance is formed poflefling a greater degree of hardnefs and elafticity than either of the former, anditis then termed fleel. Thefe three ftates appear to be modifications of the lame fubftances. Cast, or Crude Iron, contains carbon and oxj/gm- The prefence of the former appears from its coating the u- tenfils, employed in its fufion, with plumbago, a fubftance which contains nine-tenths of carbon •. alfo from the acids which diffolve it always leaving a refidue, which is puraj carbonaceous. That crude iron contains oxygen, is render- ed evident by the formation of carbonic acid, by urging th< crude iron, in clofe veffels^ in a violent heat. IS I. Crude, caff, or pig iron, is eager and brittle, and con- tains iron, carbon, and oxygen, the carbon being in a con- crete ftate feparable by mechanical divifion. Its varieties are: i. Oxygenated crude iron, which contains a fmall pro- portion of carbon, and a fuper-abundance of oxygen, is called white-iron, forge-pigs, ballaft-iron, Sec. 2. Carbo oxygenated crude iron, contains equal quanti- ties of carbon and oxygen ; known by the name of grey- iron. 3. Carbonated crude iron,—carbon fully predominating with an extra privation of oxygen. 4. Super-carbonated crude-iron,—approaching to and even becoming a true plumbago.——Philof. Mag. Forged Iron, or Bar Iron, is diftinguifhed into foft iron, and eager or brittle iron. Soft or pure iron is fo ductile that it may be extended in wires of extreme finenefs. A wire of i-ioth of an inch will fupport 450 pounds. In this ftate it poffeffes the aptitude for welding; but is almolt incapable of fufion. In proportion to its foftnefs and duc- tility it is free from carbon. It is divided into red Jhort iron and cold fhort iron. Red Short Iron, which is malleable when cold, but brit- tle when ignited, is fuppofed to derive thefe properties from arfenic, or from concrete carbon, not extirpated during the operation for rendering it malleable.----Vander Monde, monge, and Berthollet. Cold Jhort iron which is brittle when cold, but not when ignited, being diffolved in the fulphuric acid, precipitates a white powder, fuppofed by Mr. Bergman, who difcovered it, to be a peculiar metal; this precipitate he named si- derite ; but Mr. Meyer, of Stettin, has proved it to be a true phosphuret of iron, or combination of phofphorus with iron. Jt Every folution of iron is precipitated in the form of fider- ite, by the phofphoric acid. Steel is a kind of iron containing carbon only, it may be impregnated with this. 1. During the fufion, which happens when the iron is contained in the ore in nearly a difen jiged ftate, and a large proportion of coal is employ- ed ; the iron being fcarcely at all calcined, becomes charged with carbon only, the refult being fteel. 2. Afterwards, by the cementation of iron in a duftile ftate, and free from all foreign matters, with coally fubftances, the iron in both thefe cafes pairing into the ftate of fteel, or carburet of iron. The nature of the combination producing fteel, will plainly appear from fteel kept plunged for a confiderable time in crude iron, abounding with oxygen, being converted in- to foft iron. Soft iron on the other hand, kept for a time in crude iron, in which carbon predominates, is converted into fteel. Steel is duftile, whether cold or ignited ; but being tem- pered, by plunging in cold water, whilft ignited, it becomes harder, more brittle and inflexible ; but re-affumes its duc- tility by frefh ignition and gradual cooling. It may be rendered almoft of any degree of hardnefs, this depending on the degree of heat employed in the procefs of tempering* Iron may contain a much greater quantity of carbon than is neceffary as a conftituent part of fteel; in this ftate it is hard and unmalleable, and may be called hyper-carbu- RET of iron.----Dr. Pearfon, Phil. Tranf Clouet has obferved that 1-32 of charcoal is fufficient to convert iron into fteel ; and that i-6th affords a fteel more tufible, but ftill malleable. After this it comes nearer to. the ftate of caft iron, and by augmenting the dofe of char- coal, the fuf;bility is increafed, and at laft it acquires the ftate of grey caft iron. By the addition of glafs, though but a fmall quantity enters into the iron,, its properties are much changed, i Though foft to the file, yet if heated cherry red, it flies to pieces under the hammer. The caft ingot contrafts in cooling. When by careful management it is made into bars, by hardening they acquire the grain of fteel. By add- ing from 1-30th to i-20th of charcoal, it may be forged at a red heat, and gains all the properties of caft fteel; but by adding more, oidy a caft iron is obtained. The attraftion of iron for carbon is fuch, that, at a very liii4,h temperature, it will even take it from oxygen, thus iron urged in a welding heat, with carbonate of lime and clay, is changed to fteel. One-fifth of caft-iron converts bar-iron into fteel. The black oxide, with half the quan- tity of charcoal which would ferve for its reduftion, af- ford* a black iron of little tenacity. One-fixth of the oxide reftores common fteel to the ftate of iron.-----Annales de Chimie, 1798. Dr. Pearfon, by an ingenious inveftigation of the nature of a kind of fteel, called wootz, which is brought from Bombay, difcovered that it contains oxygen, and concluded, from all the properties it poffeffes, that oxygen is the ingre- dient which diftin^uifhes wootz from iisd.——Philos. I Tranf. I 77 Mr. Mufhet, on the' fuggeftion of the Editor, ofeferves that carbon exifts in fteel, in a concrete ftate, though not crude__in chemical union, however, and not in mere mixture, as in crude iron.----Philof. Mag. The tempering of iron, effefted by fuddenly cooling it after heating, feems to produce its hardnefs, brilliancy and brittlenefs, by the integrant parts, feparated by the heat, being kept and left at a certain diftance from each other; the fudden cold checking their approximation by the affinity of aggregation. Steel is capable alfo of fufion, when it is termed caft fteel. Ever fince the invention of caft fteel, it has been fuppofed to beimpoflible fo weld it to either common fteel or iron, but Sir Thomas Frankland fays, the faft is, that caft-fteel in a white heat, and iron in 3 welding heat, unite com- pletely.——Philof. Tranf. 1795. Dr. Beddoes obferves, that in the converfion of caft into malleable iron, in the revei beratory furnace, the oxygen of the imperfectly reduced metal, combines with the charcoal to form fixed air ; at the fame time another portion of char- coal is thrown into an elaftic ftate, that is, into inflamma- ble air, and burns on the furface with a very deep blue flame, on account of the adm'rxture of fixed air. By fubfe- quent experiments, the Doftor afcertained beyond doubt, the real extrication of air, varying in its nature at various periods of the procefs.-*—Philof. Tranf. 1791. The mafs of iron, weighing 1600 pounds, found in Si- beria by Pallas, is fuppofed by Dr. Chladni, to have been a fire-ball or fh'ootingftar, and that iron is the principal mat- ter employed in forming new planetary bodies. A drop of nitrous acid placed on polifhed iron and wafhed off, leaves a white fpot. On polifhed fteel it forms ablack fpot, by the coally part which is depofited during the folu- tion of the iron. AntHracolite, or incombuftible pit-coal, may be confidered as a foffil carburet, it has a metallic luftre,- marks a little, is foft and brittle. Sp. <^r. 1,468. It contains 0,90 carbon, 0,04 alumine, 0,03 filex, 0,03 iron. Plumbago, alfo called Graphite, and Black-lead, is that fhinng fubftance of a blackifti blue colour, which is ufed to make the pencils called black-lead pencils; it has a greafy fe,l, exhibits a tuberculated frafture, foils5 the hands, and leaves a black trace upon paper. It is indeftruc- tible by heat, without the prefence of air ; but with the concurrence of air, it burns, and leaves but a fmall refidue, G 2 7S One part of plumbago, and two of cauftic dry alkali, be- ing heated in a retort, the alkali effervefces, hydrogen gas is formed, and the plumbago difappears. The fmall quantity of water, in the fait, is decompofed, whence the hydrogen gas ; and its oxygen combining with the carbon of the plumbago, forms carbonic acid. The fulphuric acid diftilled from plumbago, paffes to fulphureous acid, carbonic acid being yielded, and an oxide of iron left in the retort. The nitric acid has no aftion upon plumbago, if pure. The muriatic acid has no action upon plumbago ; but, as it diffolves the iron and clay, which contaminate it, it is ufed for its purification. The oxygenated muriatic acid diffolves it; the refult being a true combuftion effected by the oxygen of the acid, and the carbon of the plumbago. If thrown, by little at a time, on fufing nitrate of pot-afb, the fait will deflagrate, and the plumbago be deftroyed ; the refidue being a ftrongly carbonated alkali, and a fmall por- tion of martial ochre. All thefe fafts prove that plumbago is a peculiar combuftible fubftance, a true charcoal combined with a martial bafis. It is more common than is imagined. The brilliant charcoal of certain vegetable fubftances, efpe- cially when formed in clofe veffels, poffeffes all the charac- ters of plumbago. The charcoal of animal fubftances pof- feffes characters ftill more refembling it: being difficult to incinerate, leaving the fame ftain, containing iron, and be- coming converted into carbonic ac'd by combuftion. During the diftillation of animal fubftances by a ftrong fire, a fino powder attaches itfelf to the neck of the retort, which may be made into excellent pencils.-----Chaptal. Carbon may be formed in the earth by the decompofition ef wood, together with pyrites ; but the origin of plumbago feems to be principally owing to the ligneous, and truly in- decompofable part of the wood, which refilling the deftruc- tive aftion of water, in its decompofition of vegetable fub- ftances, is difengaged from the other principles, and forms peculiar depofitions, and ftrata.----Chaptal. In the dominions of the King of Naples, there are wellj du<^ exprefsly for the purpofe of collefting an acidulous wa- ter, at the bottom of which a quantity of plumbago is col- Itftsd every fix months.-----Fabroni. The fame gentleman fuppofes the black mud found be- neath the pavement of Paris, is plumbago formed in the humid way. 79 Plumbago is ufed for pencils, for lubricating the fnrfa- ces, and thereby leffening the effeft of friftion of certain parts of machines, for defending iron from ruft, for polifli- ing, &c. The nature of plumbago has received confiderable illuftra- tion, frorri the late experiments and obfervations on the di- amond ; it thereby appearing to be an oxide of carbon in the firft degree. From the experiments of Guyton on the carbonic nature of the diamond, Clouet was induced to propofe the conclu- five experiment of making/o/r-iro» pafs to the ftate of fteel, by cementation with the diamond. He therefore fecured a diamond with fome filings of iron, in a cavity bored in a block of foft-iron, filling up the cavity with a ftopper of iron. The whole properly enclofed in a crucible was expo- fed to the heat of a blaft furnace, by which the diamond difappeared, and the metal was fufed, and converted into a button of caft fteel. Mr. Mufket, from an experiment he made, concluded that the diamond did not contribute the carbon, for on leaving out the diamond, the converfion took place, as he thinks, from carbon diffolved in caloric penetrating through the cru- cible, and the reft of the apparatus.----Philof. Mag. Sir George Mackenzie fufpefts, either that the carbon was derived in Mr. Mufhet'% experiment from the fand, or other materials he employed ; or elfe that what he obtained was only a combination of iron with earth, fomewhat re- fembling fteel, Sir George repeating Guyton" s experiment with compleat fuccefs----Nicbolfon's Journal, June, 1800. Iron combines eafily with fulphur by fufion, forming a true martial pyrites, or fulphuret of iron. By the combination of the sulphur with iron, in the bowels of the earth, are formed the fulphureous iron ores, the martial pyrites, or sulphurets of iron. Thefe ful- phurets are very abundant, and are evidently formed by the decompofition of vegetables.----Chaptal. The fulphurets of iron cryftallize fometimes in cubes, and often in oftahedra. The union of a number of oftahedral pyramids, forms the globular pyrites. From the decompofition of pyrites, the fulphuric acid is unengaged, which holding the iron in folution, forms the sulphate of iron, called alfo copperas, fal martis, vi- triol of iron, and/a/f of fteel This fait is alfo obtained by pouring diluted fulphuric acidon iron filings, an effervefcence arifing, from the efcape of the hydrogen gas of the water its oxygen helping to oxydate the metal, which the acid dif! so folves. It cryftallizes in rhomboids of a beautiful green colour, of which it is deprived by expofure to the air, from its efflorefcing, and lofing its water of cryftallization 5 ex- pofed to heat, it liquefies, becomes thick, and is reduced to a powder. This powder mixed with pulverifed nutgalls, forms ink-powder, only requiring the addition of water to render it fit for ufe. The fame powder urged by ftronger heat, lofes all its fulphuric acid, a martial oxide, named col- cothar, remaining. The concentrated acid is decompofed by boiling in this metal. The mixtvue being diftilled to drynefs, fublimed fulphur, and a white incryftallizable mafs, but foluble irt water, will be found in the retort. Prouft has difcovered that the common fulphates of iron contain a green and red fulphate. The green is infolubie in fpirits of wine, affords a white precipitate with alkaline prufliates, is not altered by the gal- lic acid, and its oxide contains 0,27 of oxygen. It has a ftrong affinity for oxygen, becoming red by attrafting it. The red is foluble in alcohol and uncryftallizable, gives a fine blue precipitate with alkaline prufliates, and with the gallic acid a ftrong black one; its oxide contains 0,4.8 of oxygen. It has no affinity for oxygen, being already a fur- oxygenated sulphate of iron. The green may be changed to red by oxy-muriatic or ni- J trie acid, and the common fulphate to green by fulphuratfeT J hydrogen. ■ The muriatic and other acids may by combining with either of thefe oxides that form diftinft falts.----Annales de Chimie, 1800. It may be alfo precipitated by the carbonate of pot-afi, and re-diffolved by the fuperabundant alkali, forming the martial alkaline tintlure of' Stahl. Or if it be precipitated by cauftic alkali, the aethiops is formed at once.----Maret. Iron is rather oxidated than properly diffolved by the nitric acid, which at the fame time is rapidly decompofed. To obtain the nitrate of iron, the acid muft be con- fiderably diluted. A pound of iron filings made into a pafte with water, be- ing mixed with from one to Wo ounces of nitrous acid, very much diluted and flirred with a fpatula, it effervefces and becomes a black oxide in lefs than half an hour, and if the veffel be clofed and left till next day, the furface will hi covered with a kind of champignons extremely white and feweral lines high, which are carbonate of ammoniac, the" veffel alfo now holding oxygenated nitrous gas. The water 31 and nitrous acid being deprived of their oxygen by the iron* their hydrogen and nitrogen combine whilft in a ftate of con- denfation and compofe the ammoniac in this form.----Fa- broni, Ann. de Chi. xxx. .... It is attacked by the diluted muriatic acid with vehe- mence, hydrogen gas being difengaged from the water. By concentration, a magma containing thin, flatted, deliquef- cent cryftals is formed, being a muriate of iron. This diftilled, firft yields an acid phlegm, then a non-deliquefcent muriated oxide of iron, in very tranfparent cryftals in the form of razor-blades, (hewing prifmatic colours ; there re- maining at the bottom of the retort, a deliquefcent fait of a brilliant colour, and foliated appearance, like fine large talc^ This again by fublimation yields an opake, metallic fub- ftance, polifhed like fteel, exhibiting feftions of hexahedral prifms being iron reduced.——Chaptal. Ths folution of the fublimed muriate in ether lofes ita yellow colour on expofure to the fun, and recovers it in the lhade. Iron is precipitated from its folutions, by the acid of galls, this forming the basis of ink. It is diffolved by the acetic acid with facility. This holds the metals fufpended in vegetables, it being precipitable from wine in the form of auhiops, by the means of pure alkalies. It is likewife diffolved by the acidulous tartrite of pot afh, forming the soluble martial tartar, or aperitive extracl of mars. In the oxalic acid, it yields prifmatic, a- ftringent, effervefcent cryftals of a greenifh yellow colour, foluble in water. Phofphoric acid unites with it, by adding the foluble. phof- phates to a folution of fulphate of iron. Thus is formed an almoft infolubie phosphate of iron, becoming phofphate of iron, by fufion with powdered charcoal----Fourcroy, 1800. Carbonic acid forms with it, as in the chalybeate waters, the CARBONATE of IRON. Of the fluate of iron, abd borate of iron, but little is known. Guyton has fhewn that the lap's lazuli is coloured by a fea blue fulphuret of iron, which he obtained by diffolving fulphuret of iron in nitric acid, to which, well diluted with water, pot-afh being added, a light blue precipitate is obtain- ed.----Ann. de Chi. 100. With the Pruffic acid, it forms prussiate of iron, or Pruftian blue. If the oxide of iron predominates in this combination of iron and the pruffic acid, the precipitate i„ #2' ytllowifh ; but if its proportion be lefs, the product is Pruft iian blue. The pruffiate of iron is decompofed by the oxide of mercury. Pruffiate of iron takes fire more eafily than fulphur, and detonates ftrongly with the oxygenated muri- ate of pot-afh. Lime-water faturated with the colouring principle by digeftion on Pruffian blue, is the moft accurate means of afcertaining the prefence of iron, precipitating it of a fine blue. Iron, in filings, with aneq-/ftl quantity of nitrate ofpoU afh, thrown into a crucible ftrongly ignited, detonates, e- routing numerous bright fparks, the refidue, when wafhed, being a yellow oxide of iron, called Zwelfer'sfaffrm of Mars. Iron decompofes the muriate of ammoniac, very well, yielding an aeriform fluid, half alkaline, and half hydrogenous. Iron, in filings, fublimed with muriate of ammoniac, in the proportion of an ounce to a pound, forms the martial flowers, or ens martis, being a muriate Of AMMONIAC COLOURED BY IRON. The filings mixed with fulphur, and moiftened with wa- ter, forms a mafs which fwells, and becomes heated in a few hours. The water is decompofed, the iron is ruffed* and the fulphur is converted into acid ; the hydrogen gas ex- hales, and the heat is fometimes fufficient to fet the mixture on fire. By this procefs is produced the volcano of Emery, the mafs being placed under ground. Oxides of iron give a pale green glafs, with alkalinepbof- phates, and alfo with borax, but fo much the more inclining to yellow, a9 they are more oxygenated. It may be alloyed with feveral metallic fubftances, but the only union which is ufed in the arts, is that which it contrails with tin, by which tin plates are formed. LEAD is of a bluifli white. Sp. gr. 11,352. It gives a black mark to paper, or the fingers; is the leaft fonorous, tenacious, ard elaftic of metals. It quickly tarnifhes, its furface foon becoming oxidated or rather carbonated, and it may be claffed among the moft fufible of metals. It affects the organs both of fmell and tafte. It melts before it be- comes red-hot, at 540° Farenheit. In a cupelling heat it evaporates and lofes from 6 to 8 per cent, of its weight. Abl^Jdongez obtained it in quadrangular cryftals, recum- bent on one fide. 83 Kept for fome time in fufion, it becomes covered with a grey imperfect oxide, which again expofed to a more vi- olent hent, affumes a deep yellow, and is called mafficot. This cooled by the affufion of water, ground and waffled from the particles of lead, and again expofed to a moderate heat, becomes a more perfecl and RED OXIDE of lead, called minium, containing 0,10 of oxygen. If the ruled lead is expofed to violent heat, and the wind of bellows di- rected on its furface, a fcaly yellow oxide is formed, called litharge. . Thefe oxides being fufed with coally matter, the metal is revived ; if diftilled by a ftrong heat, oxygen gas is fepa- rated ; and if urged by a very ftrong heat, they are converted into a yellow glass, or VITREOUS oxide ; fo fufible that it penetrates the beft crucibles. Sulphuric acid being boiled on lead, much fulphureous gas arifes, and an oxide of lead is formed, as well as a very cauftic sulphate of lead, which cryftallizes in the ofto- hedron and its feveral modifications. Concentrated nitric acid alfo converts it into a white ox- ide; but when the acid is weak, the lead is diffolved, and cryftals of an opake white in three-fided prifims with trun- cated angles, may be obtained, being the nitrate of lead. The muriatic acid affifted by heat, oxidates lead, and dif- folves a portion. This fait, the MURIATE of lead, cry- ftallizes in ftriated hexahedral prifms, which are flightly deliquefcent. The muriate of lead is alfo formed by adding the muria- tic acid to a folution of a nitrate of lead, the oxide combi- ning with the muriatic acid, and precipitating in a white powder. When expofed to a moderate heat, it melts into a tranfparent horn-like matter, called plumbum corneum. The oxy-muriatic acid forms a brown perfecl, or fuper- exygenated, oxide of the white or red oxides. The oxides of lead are all decompofable by the muriatic acid. It decompofes litharge of lead inftantiy, fifty or fix- ty degrees of heat being produced; the folution yielding fine opake, white, oftahedral cryftals, of a confiderable weight, foluble in lefs than their weight of boiling water. They decrepitate on hot coals, and by an increafed heat, are converted into a mafs of a beautiful yellow colour. By a fomewhat fimilar combination is obtained, the fine yel- low pigment, called patent yellov/, which may be alfo produced by the fufion of litharge and common fait. Minium or litharge alfo decompofes the muriate of ammoni- ac: and, by thus decompofmg fea fait, the feparation of foda is obtained. 84 The acetous acid corrodes lead, and affords a WHiTs Oxide, known by the name of white lead. All the oxides of lead are foluble in vinegar, forming the acetite of lead, which cryftallizes in efflorefcent tetra- hedral prifms, formerly called fait of fat urn, or fugar of lead. The oxides of lead attraft the carbonic acid of the atmof. phere with great eagernefs. Cauflic alkalies diffolve the oxides of lead, which may be precipitated by acids; and, in a metallic form, by mere concentration : the alkali acquiring a peculiar faint tafte. Puie alkalies being added to a folution of the muriate of lead' a magma is direftly formed, occafioning a fpecies of mira- culus mundi. Sulphur combines readily with lead, forming a brilliant -femi-cryftallized mafs, termed sulphuret of lead, which affumes the forms of the cube and oftohedron, with their modifications, and is the artificial galena. It has no known union with carbon or hydrogen. It u- nites with phofphorus, forming a white, brilliant phosphu- ret of lead, difficult of fufion and foon tarnifhing. With arfenic it forms a brittle, black alloy ; with bifmuth, the alloy is harfh ; with antimony, grey and brittle ; with mercury, a cryflallizable amalgama; with tin, a very ufeful folder ; but with zinc, its union is very weak. As lead has the property of being eafily oxided and of deftroying other bafe metals, it is employed in refining the nobler metals. This is done in a cupel, a veffel made of afhes, which the lead will not eafily vitrify, and which be- ing porous will abforb the litharge as it is formed, and leave the furface of the alloyed metal to be the better afted on by the fire. This procefs is termed cupellation. Befides its other ufes, lead, from its oxides promoting the vitrification of other metallic oxides and of earthy bodies, is employed to glaze pottery ; and its oxides enter into the compofition of glafs, the fufion of which they affift, and render it fitter for brilliant ornaments. It is ufed in enamels, and alfo to form pigments. The oxides are alfo ufed to a- mend the appearance and tafte of wines and brandies; and to harden oils, and render them more drying. Dffolved in culs, they ferve as the bafis of plafters. As the alkalies, lime-water, fulphuric and muriatic acids, decompofe the acetate of lead, throwing down the oxide in a white powder, it is recommended as a re-agent to detect the prefence of thefe fubftances. - S5 To deteft the admixture of lead in wine, equal parts of ovfter-fhells and crude fulphur, may be kept in a white heat for fifteen minutes, and when cold, mixed with an equal quantity of acidulous tartrite of pot-afh, and put into a ftrong bottle with common water to boil for an hour ;; and then decanted into bottles holding an ounce each, with 20 a ops of muriatic acid in each. This liquor precipitates the leaft quantities of lead, copper Sec. from wines in a ve y fenfible black precipitate.----M. Hanhemann. Bibl. Phyf. ECAl iron might accidentally be contained in the wine, the muriatic acid is added to prevent its precipitation, and its being miftaken for the precipitate of lead. From this property of precipitating the lead of a dark co- lour, the alkaline fulphurets, and even the fulphurated hy- drogen gas, render the folutions of acetate of lead, a jym pathetic ink. TIN is of a filver greyifh white, very foft. Sp. gr. of Cornifh tin, melted and not hammered 7,291. hammered 7,299. It is the lighteft of all metals ; is exceedingly duc- tile, but inconfiderably tenacious. It is very flexible, and crackles when bended. It fufes at 4100 i During its fufion, the furface, expofed to the air, is foon covered with a pel- licle of grey, imperfecl oxide, which by a greater heat becomes a perfecl white oxide, called putty, ufed to po- lifh hard bodies, and convert glafs to enamel. Kept in fu- fion eight or ten hours in a lined crucible, and in contact with charcoal, it becomes more white, hard, and fonorous. It takes fire with a violent heat, a white oxide fubliming, and part of the tin being converted into a glafs of an hya- cimhine colour. Geoffrey. After repeated fufions, an affemblage of prifms are ob- tained, united together fideways. De la Chenaye. All the acids attack reguline tin, requiring for their figu- ration more of the imperfeft than of the perfeft oxide. The fulphuric acid oxidates it without diffolving it, but the fulphureous acid forms with it a sulphite, or sul- phurated sulphite of tin.---Fourcroy, 1800. Water is fufficient to precipitate this oxidated metal. Mr. Monnet has obtained cryftals, the sulphite of TIN, which refemble fine needles, interlacing each other. H 86 In pure nitric acid it is directly precipitated in a white oxide. The acid muft therefore be confiderably diluted and no heat employed ; thus the nitrate of tin may be ob- tained. This nitrate burns with a white and thick flame like that of phofphorus ; and detonates when well heated into a cm- icible. On diflillation it boils up, and fills the receiver with a white vapour, fmelling like nitric acid. By adding a folution of gold to the folution of tin in the nitric acid, a beautiful purple precipitate falls. Tin is diffolved by the muriatic acid, cold or heated, a fetid gas being difengaged. The folution is yellowilh, and the muriate of tin cryftallizes in needle dike forms, and attrafts humidity. The oxide in this fait is imperfeft, and eagerly takes up more oxygen if prefented to it. This it does if brought in contaft with oxy-muriatic acid in an elaftic ftate, alfo in the following procefs. When amalgamated with one-fifth of mercury, and dif- tilled with an equal quantity of the whole, of corrofive fublimate, an infipid liquor firft comes over, and then white vapours, which condenle into a tranfparent liquor, that e- mits a confiderable quantity of vapours, by mere expofure to the air. This is the fmoking liquor of Libavius; ap- pearing to be an OXVGENAT.ED MURIATE of TIN. It is diffolved by the oxy-muriatic acid with vehemence, and when the acid is highly concentrated, a magma is ob- tained, refembling pitch, which hardens in time. It is diffolved in the common aqua fortis, prepared with falt-petre of the firft boiling., for the compoiitiuii for fear* let dye, from cochi'ielle. This folution often difappoints, from the variable proportions of the muriate of foda, and nitrate of pot-afh; when it contains too little muriate, a precipitate falls ; and when the acid is in excefs, it affords an obfeure colour. The moft accurate proportions for a good folvent of tin, are two parts of nitric, and one of mu- riatic acid- Tin and its oxides are diffolved, but the latter more free- ly, by the cauftic alkalies. It is likewife flightly foluble in the vegetable acids ; but the carbonic acid does not appear to aft on it at all. It has no known union with nitrogen, hydrogen, or carbon. Charcoal renders it refraftory, and with phofphorus it forms a brittle phosphuret.----Fourcroy, 1800'. Combined with fulphur, it forms sulphuret of TIN* e>f a bJuifh grey colour, of a metallic fplendour, and aci- 87 cular texture. But if the combination is with the perfect oxide, as in the following procefs, then is formed aurum mufivum, or mofaic gold, ufed by artifts in many varnifhed works. Eight ounces of tin and of mercury being amal- gamated together, are put in a matrafs with fix ounces of fulphur and four of muriate of ammoniac ; the bottom of thematrafs being ignited, the fulphuret fublimes; and if the heat is fuch as to make the mixture take fire, it is fub- limed of a dazzling colour in large hexagonal fcales. The tin, minutely divided by its amalgamation, is oxidated by the muriatic acid of the muriate of ammoniac; and the hy- drogen, difengaged from the water of cryftallization of this: fait, combining with fulphur and caloric, forms a fulphur- ated hydrogen gas. Miniated oxide of jjn^and mercury, united with fulphur in the form of cinnabar alfo rifes ; the remaining oxide of tin and fulphur forming the aurum mu- fivum. It may be prepared without either mercury or muriate of ammoniac, from eight ounces of tin precipitated by the car- bonate of fod;i, from its folution in the muriatic acid, mix- ed with four ounces of fulphur. A precipitate from the nitrate of tin, by liquid fulphur of iiot-afh being dried, and put into a retort, with half its weight of fulphur, and a quarter of the muriate vf shmuo- niac, the fulphuret of tin will be formed at the bottom of the retort, and of a moft brilliant appearance.—~—Brugna- telli. Being amalgamated in the proportion of two ounces to a pound of mercury, and urged by a violent heat for five hours in a fand bath, no mercury was difengaged, but the tin was cryftallized ; the lower part of the amalgam being compofed of grey brilliant cryftals in fqtiare plates, thin towards then- edges, leaving polygonal cr.'iacs bitv/eefl-each. E.Ciy ounce of tin relaining in cryftallization three ounces of mer- cury.----Sage. It may be combined with other metals in various propor- tions. The malleability of gold is impaired even by an ex- pofure to us fumes. Silver alfo fuffers a diminution of its malleability by being fufed with it. When alloyed with copper, it forms bronze, or bell-metal ; wi.h a very fmall proportion of iron it becomes harder, and more fono- rous. Of fimilar mixtures the metallic _#«■«/« for reflecting telescopes are call, fuch as z parts of copper, , of t.n, and i-i6th of arfenic, ' 88 Three parts of tin, with five of bifmutb, and two of lead, forms an alloy, which has been termed the soft solder, it liquifies in boiling water.----Lichtenburg. Two parts of tin with one of bifmuth afford, according to Wallerius, the compound called tutenag, an appellation which is given in the Eaft Indies to zinc.----Gren. One part of tin and one of zinc being melied together and mixed with two of mercury, then agitated in a box rub-' bed with chalk, forms an amalgam which wonderfully augments the power of electrical machines____Kien. mayer. Its amalgamating with quickfilver, occafions its being em- ployed in the formation of mirrors, i part of tin, i of lead, j of bifmuth, and 2 of mercury, form an amalgam employed for covering curvilinear glass mirrors. When combined with lead and antimony, it forms a mix- ture called pewter, very generally employed in fabricating veffels for various domeftic purpofes. It is alfo employed in the compofition for Printer's types. Tin is alfo employed in enamelling. A mixture of lead and tin, 100 parts of" lead to 15, 20, 30, or eveh 40 of tin, is to be fiift calcined, 100 parts of the above calx fui'ed in a potter's furnace with 100 of fand, containing nearly a third cf tale, and a c cr 30 '_>" muriate of foda, form the cora- pontion for earthen -ware. For enamelling on metal, the fand is previoufly calcined with a fourth part cf muriate of foda, and even of minium. Y'.uxrt for the colours are generally fmiilar compofitions, ex- rept tha; lead tarni/hes with fome colours. For delicate co- lours therefore fimlar compofitions to the following maybe ufed: Three parts of far.d, ore of chalk, and three of bo- ) ax ; or three cf gl.ifs, one of borax, a fourth of nitre, and one . .' white ox;de of antimony. r,11 Hiinv on ?,„„>„; r^?.- u? p^fovm^ either on the raw or on the bkoi enamel. The colours are produced by the metallic oxides. The oxide of gold forms purple ; iron, by peculiar management, red; lead, antimony, and filver- yclJow; copper—green ; cobalt—blue ; manganefc—violet. From the affinity cf" copper with tin, it admits of being tinned, or cf having its furface covered with tin. For this purpofe the copper is firft fcraped, or cleaned by an scid, then heated, fome refinous fubftance bein^ applied to pre- vent oxidation, and the tin is rubbed overTts fuiface. If care be taken to prevent oxidation, and a proper degree of heat be employed, the tin may be made to enter into com- bination with iron, and iron may thus have its fiuface tinned, S9 ZINC, is in colour between the filvery white, and lead rrey. Sp. gr. 7,190------Fourcroy, 1800. It melts as foon as ignited, when it inflames and fub- limes in white flocks, which are called phdofophical wool, pompholix, ornihilalbum, and is a true oxide of zinc. When laminated into thin leaves, it takes fire by the flame of a taper, burning with a flame of a blue colour, mixed with green. M. de Laffone confiders it as a kind of metallic phofphorus. . . . From its ftrong attraction for oxygen in a red heat, it de- compofes water: much hydrogen gas being difengaged, but mixed with carbon? derived from the zinc. Zinc is diffolved by all the acids. Sulphuric acid, diluted, diffolves it in the cold, and pro- duces much pure hydrogen gas ; a black powder, which is plumbago, from the admixture of iron, is feparated, and a fait is formed in compreffed tetrahedral cryftals, terminated by four fided pyramids. This is the SULPHATE of ZINC, vitriol of zinc, white vitriol, or white copperas. This fait is not much altered by expofure to air, when pure ; but its acid efcapes, at a degree of heat, lefs than is required by the fulphate of iron. This fulphate uniting with the alkaline fulphates, forms triple falts, from which may be precipitated, a white oxide foluble in pot-afh and foda.-----Fourcroy, 1800. The nitric acid attacks zinc with vehemence, even when diluted with water; and, by flow evaporation, yields cry- ftals in compreffed and ftriated tetrahedral prifms, termina- ted by four fided pyramids, being the nitrate of zinc, which is deliquefcent. It emits red vapours when heated ; becoming foft, and preferving that f ftnefs for fome time. The muriatic acid attacks zinc, with effervefcence: hy- drogen gas is produced, and an irreducible oxide of zinc is depofited in black flocks. The folution thickens by eva- poration, without cryllallizing, a concentrated acid efcapes, and the muriate et zinc will itfelf fubliine by diftilla- tion. Of all known bodies, Girtanner fays, zinc unites moft readily to oxygen. It takes it from almoft every other body, which renders it ufeful in detefting the fmalleft quantities cf oxygen. It was chiefly by means of zinc that I have heen enabled to feparate the oxygen of the muriatic acid from its bafe.----Ann, (ke Cb, Can. 100, 90 The zinc of commerce, Prouft remarks, contains alfo iron, lead, and copper, which precipitate in an oxided ftate in a black powder, during the folution of zinc in the acids. In whatever acid it is diffolved, he obferves, it conftantly abforbs the fame portion of oxygen. In the muriatic and fulphuric acid, where it is perfectly oxided, the iron is at its minimum of oxidation, and therefore does not change by the addition of the gallic acid, which it will however do by expofure to the air, or by the addition of a few drops of oxy-muriatic or nitric acid. Thus alfo the carbonate be- comes yellow on expofure to the air, the iron pafling readi- ly to its maximum of oxidation. In two pounds of faturated folution of fulphate of zinc pit ono: ounce of nitric acid, then by the addition of pot-afh the excefs of acid is faturated, and a white fubftance, foon becoming yellow, is precipitated : when white parts aredf- coverable in this yellow precipitate, it may be concluded no iron remains in the foluticn. If the zinc contain mariga- nefe, carbonate of pot-afh is to be added, but fliort of the total precipitation of the zinc ; leaving the fluid on the fo- lution two or three days, that if any manganefe have been precipitated, it may be re-diflolved by the acid, the zinc precipitating in its place. The fulphate of zinc thus puri- fied will fuinifh the fine white oxide of zinc fo defira- ble by painters.——Ann. de Chim. Cah. 103. The pure alkalies, boiled on zinc, obtain a yellow co- lour, and diflJve part of the metal; and added to a foluti- on of zinc in fulphuric acid they throw down a white ox- ide, with a confiderable increafe of weight beyond that of the metal. It detonates ftrongly if mixed with nitrate of pot-afh, and thrown into an ignited crucible. The muriate of ammoniac is decompofed by it, fimply by trituration. Sulphur cannot be combined with zinc by fufion, but is faid by Dehne and Guyton to combine with the oxide. Gold, Silver, Piatina, and Nickel, are rendered brittle by it. Mercury amalgamates with it, being ftirred into it before it hardens after fufion. Neither had nor bifmuth enters into combination with ain'c in fufion. Fufed with antimony it forms a hard and brittle alloy; with tin and copper it forms bronze; and with copper alone, it forms brass, or yellow copper. From fimilar combinations, but containing lefs zinc than enters into the 91 compofition of brafs, are formed tombac, prince's metal, milor, and Pinchbeck's metal. Lead is precipitated from acids by zinc ; thus is formed llfemanns lead tree, a fmall roll of zinc being fufpend- ed in a folution of acetite of lead, in the proportion of two drams to fix ounces of ware. The tinning of brafs pins is thus performed : A veffel is filled by layers of brafs pins and plates of tin, one of thefe plates being uppermoft and undermoft. The veffel has then a folution of cream of tartar poured in, the acid diffolves the tin, which the zinc of the brafs precipitates on them in a reguline ftate, by which, after five hours boiling, they are uniformly tinned.----Tranflator of Gren's Principles. ANTIMONY is a white, brilliant femi-metal. Sp. gr. 6,860. volatile and difficult of fufion; but when melted, it emits a white fume, called argentine fnow, or flowers of antimony, being a sublimed oxide of antimony, in brilliant prifmatic acicules. The metal whilft cooling flow- ly, cryftallizes in oftahedra, and generally affumes a ftellu- lar form, on its furface. It is very flightly changed by ex- pofure to air. When combined with fulphur in the earth, or artificially, it forms a sulphuret of antimony; this, when native, is an ore of antimony, commonly called crude antimony, or improperly, antimony. Gvude antimony, reduced to powder and expofed in a fhallew veffel to a flow heat, gradually lofes its fulphur; and the oxygen of the atmofphere uniting with the antimony, converts it to a grey or imperfeft oxide. This being urged by a more violent heat, becomes a reddifh, and partly a tranfparent glafs of antimony, vitreous oxide of an- timony, which when corrected by being blended with wax, forms the cerated glass, of antimony. Tin, copper, filver, or iron, being fufed with crude an- timony, unites with the fulphur, and feparates the antimo- ny, which, according to the metal employed, was called regulus of Mars, Venus, Sec. It is found at the bottom of the crucible, in a cryftallized metalline form. Antimony is feparated from the fulphuret, or crude anti- mony, by detonating three parts of crude tartar, two of crude antimony, and one of nitrate of pot-afh. After fu- fion, the antimony will be found in a reguline form at the bottom of the crucible covered with brown fcoria, which 02 contain the fulphurated alkali, combined with imperfeft an- timonial oxide, and which, on folution in water, lets fall a brown precipitate, an hydrogenated fulphuret of antimony named the sulphurated oxide of antimony, and formerly Kermes mineral. But, if an acid be added the precipitate is of a fainter, and at laft, of" an orange col'our This laft precipitate is alfo called the fulphurated oxide of antimony, and was formerly termed the golden fulphur of antimony. It differs from the former precipitate, in con- tainmg a greater proportion of the hydrogenated fulphur Antimony is completely diffolved in the dry way by alka line fulphuret; thus equal parts of fixed alkali being melted with crude antimony, a fulphuret is formed containing an timony, being the sulphuret of antimony, common- ly-called liver of antimony. It equal parts of nitre and crude antimony be detonated and fufed, another combination of alkaline fuhhurei> *vitb antimony is obtained, formerly called faffron 'of antimony. un being bcled wah water, hydrogenated sulphu- Rated oxide is precipitated. By ufing the fulphur of antimony, with three parts of the nitrate, the refidue m the crucible, after detonation, is oxide of antimony, fixed alkali, a portion of nitrate not decompofed, and a fmall quantity of fulphate of pot-afh I his compound is called the folvent of Rotrou. Water deprives it of the falts, leaving only a white peifeft oxide of antimony, which is called wafbed diaphoretic antimony. It to the water holding thefe falts in folution, a fmall auan- tity of acid be added, the fmall portion of oxide held i'n fo- lution by the alkali, is let fall. This precipitate has been called cerufe of antimony, or the materia perlata of Ker- kri.':q;us. One part of pot-afh being melted with five of crude anti- mony a denie, vitreous, blackifti brown matter is obtain- ed, inf luNe ,n water, and not becoming moift in the air. It is a fulphuret, but holding lefs fulphur than the native fulphuret. It has been called medicinal regulus of antimony magnefia, opahna, Sec. J All .be acids, except the carbonic, diffolve the imper- feft ox.de of tins metal. The fulphuric, nitric, oxy-mu- nat.c, and n.tro-munat.c acnis alone attack recline anti- niony. ° rrl^A^fl fd by b01'!i5?^rc" •''"timony, is partly de- composed. Sulphureous gas is firft feparated, and fulphur itfelf iiiblimes, towards the end ; an oxide is formed as well as a fmall quantity of sulphate of antimony which is very deliquefcent, and eafilv deconmofpH ' 93 It decompofes the nitric acid with great facility, part of the antimony is oxidated, forming the bezoar mineral, and a portion is diffolved, forming a nitrate of antimony, decompofable by heat, and very deliquefcent. The muriatic acid afts on it only by a long digeftion. The nitro-muriatic acid is its moft convenient folvent. The folution has no colour. The oxy-muriatic acid poffeffes al- moft equal powers : thus, two parts of the corrofive muriate cf mercury and one of antimony being diftilled together, a flight degree of heat drives over a butyraceous matter, the sublimed muriate of antimony, or butter of anti- mony. The acid, as in the corrofive muriate of mercury, being in an oxygenated ftate. The fublimed muriate of an- timony becomes fluid by a very gentle heat, and is thus eafily poured from one veffel to another. It fometimes cryftallizes in hexahedral prifms with dihedral fummits, two fides of the prifms being inclined. Diluted with water, a white oxide, of antimony falls, which has been called pow- der of Algaroth, or mercurius vita. Wine and the acetous acid diffolve it. The acid of tartar forms with the grey oxide the well- known fait, the antimoniated tartrite of pot- ash, emetic tartar, or ftibiated tartar. Chaptal remarks that this preparation often varies in its ftrength, and wifh- ing to eftablifh an uniform procefs for its formation, propo- fes tranfparent glafs of antimony to be boiled in water, with an equal weight of acidulous tartrite of pot-afh, until the fait is faturated : by filtration and flow evaporation cryftals are obtained, in trihedral pyramids, of a fufficiently uniform degree of emeticity. The gaftric fluid diffolves this femi-metal, as is proved by the famous perpetual pills. Simple water has alfo fome action upon it, fince it becomes purgative by remaining in contact with it. Lime, or Iimer-water, digefted for fome days, even with- out heat, on powdered antimony, yields a beautiful red fulphurated ox;de. Ammoniac being diftilled from crude antimony, a pulverulent fublimate of a purple colour is ob- tained, being a fulphur of antimony, with bafe of volatile alkali. Antimony and mercury unite with difficulty. It combines with gold, filver, platina, copper, iron, and zinc, rendering them brittle, and from its volatility, may be driven off again by a fufficiently ftrong heat. Lead and antimony afford a brittle alloy ; a fourth part of antimony added to lead makes a compound fit for printer's types, either with or without zinc or bifmuth. 94 Three parts of white oxide of antimony, iz of white oxide of lead, i of fulphate of alumine, and i of muriate of am- moniac, firft heated weakly for fome hours and then kept in a red heat forms the fine metallic pigment, Naples yellow.— Tranftator of Gren's Principles. Tin is rendered by it more brittle, hard, and fonorous. 3 parts of tin, 2 of lead, and i of antimony, is faid to be ufeful for making ship-nails. An infpiffared folution of glafs of antimony in muriatic or tartareous acid affumes a gelatinous form, the jelly not be- ing again foluble in water or by excefs of acid. This Vau- quelin has difcovered to proceed from the exilfjnce of filica in the glafs of antimony, he having found it in the proportion of 12 parts in the ioo, being derived ei.her fiom the cruci- ble, or from the gangue, being ftrongly afted on by the ox- ide of antimony as well as by that of lead. To account for the folution of filica in the tartareous acid, he remarks, that although filica eludes, in its ordinary ftate, the aftion of the moft powerful acids ; yet, when joined with an alkali, ano- ther earth, or a metallic oxide, it may then be diffolved evtn by a weak acid. Repeated cryffellizaticns are not fufficient to feparate the filica, but in making the emetic tartar he propofes the folu- tion to be filtered hot, and evaporated to drynefs, taking care not to burn it ; and then re-diffolved and cryftallized, as the filica will entirely feparate towards the end of the evaporation.-----Ann. de Ch. 1800. BISMUTH, or Tin glafs, is white, darkened by a fhade of red, or yellowiffr red. It yields a little under the ham- mer, but is fo brittle, that it may be thus reduced to pow- der. Sp. gr. 9,812, and, next to tin, is the moft fufible of all metallic bodies. It tarnifhes, but does not ruft in the air. When expofed to a ftrong heat it burns with a blue flame, and fublimes in a yelJowifh fmoke, which forms, when condenfed, an oxi-de of bismuth, or the flowers of bif- muth. Thefe flowers may be vitrified into a brownifh glafs. By a lefs heat it is calcined into a powder, which is a lefs perfecl oxide. It readily combines with fulphur by fufion, and forms a bluifh grey artificial ore, or sulphuret of bismuth, 95 which cryftallizes in beautiful parallelipepids, united by their ends, at right angles. Sulphuric acid being boiled on it, the bifmuth is partly diflblved, forming the sulphate of bismuth, which is very deliquefcent. The nitric acid is fpeedily decompofed by bifmuth ; nitrous gas is feparated, whilft the oxygen combines with the femi- metal, and a portion is diffolved which yields rhomboidal, tetrahedral prifms, terminating in tetrahedral pyramids with unequal faces, being the nitrate of bismuth, which efflorefces in the air. The muriatic acid does not aft on it, but by the aid of heat and concentration ; the muriate of bismuth is deliquefcent and difficult of cryftallization. The acetous acid does not take up the oxides of bifmuth, as it does thofe of lead. Water precipitates this femi-metal from all its folutions ', the precipitate, when well wafhed, is employed as a white paint for the complexion, and is known by the name of magiftery of bifmuth: but fulphurous hepatic vapours, and even the animal tranfpiration, blacken it, and reduce it to a metallic ftate. It is alfo employed in pomatums to blacken the hair. Its oxides are diffolved by fat oils into a tenacious mafs refembling plafters. It alfo combines with fulphur by fufion. Its various folutions form pellucid fympathetic inks, which are curious from the facility with which they become black with alkaline fulphurets or fulphurated hydro- gen gas. It renders gold brittle, and communicates to it its own colour ; but it does not render filver fo brittle as it does gold. It diminiflies the red colour of copper ; with lead, it forms an alloy of a dark grey colour ; to tin it gives a great- er degree of brilliancy and hardnefs ; with iron it does not unite, but by a violent heat; and with mercury it amalga- mates and forms a fluid alloy. It is ufed for pewter, foft folder, printers types, Sec. COBALT is white, inclining to a bluifh grev ; and if tarn.fhed, to red, Sp. gr. 7)645. When very pure it is malleable, in fome degree, in a red heat. Even when pu- reft it is magnetic, and it is generally contaminated with a.fen.c. It is not volatile in clofe veffels, and when pure, is as difficultly fufible as iron, but i-s rendered more fufible, 96 and of a brown colour, by the addition of arfenic. After fufion its furface frequently affumes a reticular form. It calcines with more difficulty, as it is more pure ; its oxide being of fo deep a blue, as to appear black. Whilft in its metallic ftate, it tinges no earthy fubftance; but in contact with fluxes it readily calcines, hence, being treated with borax, foda, pot-afh, microcofniic fait, in a ftrong heat it tinges them blue. In fufion, it will not mix with bifmuth, lead, or filver; but with bifmuth it unites by the mediation of nickel; but it does not amalgamate with quickfilver. With arfenic it burns with a bluifh or white flame. With concentrated fulphuric acid, it unites and yields reddifh cryftals, with quadrilateral columns, with dihedral fummits, the sulphate of cobalt. It unites with the nitric acid readily, and with effervef- cence ; the folution is reddifh, and yields hexahedral cry- ftals, the nitrate of cobalt : if arfenic predorai- nates, the folution is firft whitifh, and then becomes red. Cobalt diffolved in nitro-muriatic acid and mixed with i* as much of nitrate of zinc ; and a lixivium of pot-afh being added, the precipitate ignited to whitenefs forms a fine green colour for painters.----Tranf. of Greti'i Principles. The muriatic acid diffolves it with difficulty, requiring heat 5 the folution, which is of a peach red, holding in fo- lution the muriate of cobalt. If contaminated with much nickel, the above folutions are greenifli. Its oxides yield to the acetous acid and to ammoniac; the folutions with the former, are red and pur- ple ; with the latter, blue when hot.—-With the nitro-mu- riatic acid, the folution is red ; if contaminated with iron, brown. One part of cobalt in 3 of diluted nitric acid, farther diluted with 24 of water, with the addition of 1 part of muriate cf ammoniac or of foda, makes Hellofs fympa- thetic ink ; for though letters traced by it are invifible while cold, yet when very moderately heated they appear green, if the cobalt retains much iron, but blue, if free frcm iron. By 1 part of oxide of cobalt, and 16 of diftilled vinegar evaporated to an eighth, and i-4th of the cobalt of muriate of foda, is formed Ilfemann's blue fympathetic ink, fomewhat fimilar to the former. Its folutions are not precipitable by zinc. It was employed to give a blue colour to glafs, long be- fore it was fuppofed to contain a femi-metal. 9? The ores of cobalt are torrefied in Saxony in furnaces, the arsenical vapours attaching themselves to the sides, yield the arsenic of commerce. When the oxide of cobalt is cleared of arsenic, it is known by the name of zaffre. The zaf- fre of commerce is mixed with three-fourths of sand. This oxide fused with three parts of sand and one of pot-ash, forms a blue glass, which when pounded, sifted, &c. forms SMALT. Brugnatelli by dissolving the grey oxide of cobalt or zaf- fre in caustic liquid ammonia, obtained a liquid ammoni- uret of cobalt : by evaporation to one-fourth he pro- cured two substances, the one of whicl* precipitates of a yellow colour, the other remaining dissolved, and giving to the water a red colour. The yellow substance is a pure ox- ide of cobalt, and dissolved in ammonia forms a pure am- moniuret of cobalt. The colour of this is yellow and sometimes rose-red: the acids do not decompose it, but the muriatic acid discolours it; and the prussiate of pot-ash. renders it grey, and produces a precipitate of the same colour. The sulphur of pot-ash gives it a deep colour, approaching to black, and sulphuret of cobalt is precipitated. Borate of soda is decomposed by it, and bo- rate of cobalt precipitated. From the red solution, filtered from the yellow oxide, he obtained an acid which he calls the cobaltic acid. This acid he obtained in a concrete form, of a red or yellow colour, and sometimes colourless; without smell, and of a sharp, and not unplea- sant taste. It reddens turnsole, is soluble in water, and decomposes sulphurets of alkali. It precipitates ammoniu- ret of copper of a light green, and that of zinc of a clear white, and the sulphuret of copper of the same colour as the ammoniuret; nitrate of silver it precipitates white, as well as the nitro-muriate of tin; the nitrate of mercury of a light straw-colour; the. acetite of lead, white; lime-water, a white coagulum ; tincture of galls, yellow; and it prccipi- ratcs the acetites and muriates of barytes, but docs not affect the solutions of gold and platina, It is separable by alcohol from its solution in water. Used as a sympathcti'? ink it changes brown, not green or blue. "With soda ii, forms a salt of irregular crystals; whh pot-ash, square crystals ; and with ammonia, a salt soluble in its acid; and with baryt, ah opake, difficultly crystallizable salt.----Ann. de Chim. xxxni. Smalts are used in the preparation of cloths, laces, linens, muslins, threads, 8tc. When it is separated b;, •.•,-at*;r from 98 the grosser particles, it is called azure. The azures mixed with starch form the blues used by laundresses. Besides being used for colouring glass, it is also used for blue paint- ings on porcelain. The most simple way of obtaining cobalt in its metallic state, is to reduce it from smalt, by fusing one part of smalt with six of soda. NICKEL is a metallic substance of a greyish white, when pure ; but shaded with red or yellow, when"impure. Sp. gr. 9.000. It is difficultly purified. When purest it is magnetic, and hence has been deemed to contain iron, even when it ex! hibits no other sign of its containing any, but Mr. Kirwan thinks without sufficient reason. It is malleable in a consi- derable degree, and calcines slowly in a strong heat: if pure, the oxide is brown, if impure, greenish ; rising in tuberous vegetations, proceeding from iron or arsenic. When pure, it requires as strong a heat as cast iron, the impure melts more easily. Fused with sulphur, it forms a hard low mine- ral ; and with the sulphuret of pot-ash, a compound resem- bling the yellow copper-ores. It does not amalgamate with mercury. The sulphuric acid distilled on it, leaves a greyish resi- due, which when dissolved in water, communicates a green colour. This is the sulphate of nickel, which forms octahedra with truncated angles, but which effloresce in the air. The nitric acid, with heat dissolves it, and yields the aitrate of nickel, in crystals of a beautiful green, in rhomboidal cubes. The muriatic dissolves it also, with heat, but more slowly; the muriate of nickel forming in long rhomboidal octahedrons, of the most beautiful eme- rald green. The acetous acid acts only on its calces. The fixed alkalies precipitate the nickel in the foregoing solu- tions, greenish white. Ammonia also precipitates them, but in excess re-dissolves them, the solution being blue; even metallic nickel yields to ammonia. It is not precipitable by zinc, though m some measure by iron, but does not amalga- mate with iron. D MANGANESE is of a greyish white, but soon darkens by exposure to the air, Us surface becoming friable and 99 dark, as it becomes oxidated, the perfect oxide being black. It is in no degree malleable. Sp. gr. 7.000.---- Ilielm. By heat it is converted into a black oxide, and, if strongly urged, affords a glass of a yellowish brown. This metal is less fusible than crude iron, and unites by fusion,* with all the metals, except mercury. The oxide of manganese af- fords a prodigious quantity of oxygen gas ; and with char- coal, the carbonic acid.----Kept in fusion, with phosphate of soda, upon charcoal, a transparent glass is formed, which curiously changes from the colour of a ruby to a colourless state, and again becomes coloured, according to the quanti- ty of phosphate, and to its exposure to the interior or exte- rior part of the flame. From its affinity with oxygen it decomposes water. The habitudes of manganese with respect to acids are re- markable. Its imperfect oxide is dissolved by all the acids; its perfect oxide is dissolved by no acid, whose base or radi- cal is fully saturated with oxygen, and thus incapable of taking up more of this principle. On the contrary, if the radical of any acid is capable of absorbing more oxygen from the perfect oxide of manganese, or if it be rendered thus capable of taking up more oxygen, by the addition of some sugar, gum, or the like, the oxide is then converted into an imperfect one, and as such will be dissolved by the acid. These solutions are colourless, and become brown, as the oxide approaches to perfect oxidation, or from particles of iron.----Gren. On this principle the sulphate of manganese may be had from the black or perfect oxide; the nitrate from nitric acid and imperfect oxide, or from nitrous acid and perfect oxide. Muriatic acid thus dissolves, even the perfect oxide, becoming oxygenated, but being volatile, the oxygen flies off, and the muriatic acid continues to dissolve the oxide thus rendered imperfect. With the fluoric acid, a salt of sparing solubility is formed, so likewise with the phosphoric acid. The acetous acid acts but weakly on it: the oxalic dissolves the manganese, and the black oxide of manganese also. The acidulous tartrite of pot-ash dissolves the black oxide, even in the cold; and, added to any solution of manganese, precipitates a true tartrite of manganese. The carbonic acid attacks both manganese and its black oxide. Muriate of ammonia being distilled with the oxide, the oxygen of the latter unites with the hydrogen gas of the alkali, and forms water, nitro- gen gas escaping. Manganese itself does not appear to 100 combine with sulphur; but eight parts of oxide, with three parts of sulphur, form a mass of a .greenish yellow colour, which acids attack with effervescence, and occasion an lies'. patic smell. Manganese is precipitated frcm its solutions by the alkalies, in the form of a gelatinous matter, which becomes -black as it absorbs oxygen. From the rapidity with which this change takes place, it is well calculated to form an eudiometer, by being diffused on the internal surface of proper vessels, and marking, by the ascension of water in a graduated tube, the absorption of oxygen. If one part of the native oxide of manganese, and three parts of nitrate of pot-ash, be melted in a crucible till no more oxygen gas is disengaged, a greenish friable powder is obtained, termed chamelion minceralis, an alkalixe oxide Of MANGANESE. The solution of this is first blue, oxide of iron then sepa- rates and from its yellow colour renders the solution green, this subsiding the blue re-appears; then from the oxygen it absorbs from the air, the manganesian oxide becomes red- ' dish, brownish, and at last black, when it subsides and leaves the fluid colourless. Its affinity with oxygen exceeds perhaps drat of any other metal. Its combinations with other metals are at present but little known : but from its great affinity with iron, and.from man- ganese being never obtained free from iron, it seems that they admit of an union. Scheele has proved, that the ashes of vegetables contain manganese ; and that it is to this mineral, that the blue co- lour of calcined pot-ash is owing. Of all metallic substances it is, after iron, the most generally, though minutely diffused through the earth. To various species of uncoloured glass it gives various hues according to the quantity of oxide, and its degree of oxidation. If a very slight portion be used to glass discoloured by coally particles or iron, it renders it colourless; it is hence called glass7naker's soap. It is also employed to give a black glazing; to pottery- ware. 101 URANITE, or the metal of uranochre, of the pitch- blende, and of the chalcolite, or green mica, discovered by Klaproth, in 1790, is of a dark steel or iron grey ; inter- nally browner. Sp. gr. 6,444. It is soluble in nitrous acid; it does not appear that other acids have been tried. It is infusible alone before the blow-pipe ; but with mi- cronicosmic salt, or concrete phosphoric acid, it becomes a grass green glass ; and with soda or borax only a grey opake scoriaceous bead. Its oxyde is yellow, and is eafily foluble in acids. With dilute fulphuric and the concentrated acetous acid it yields yellow crystals; with the phofphoric, an amor- phous, white, difficultly foluble mafs ; and with the nitrous and nitro-muriatic acids, greenish yellow crystals. The precipitate thrown down from these two last mentioned folu- tions, by sulphurated ammoniac, is of a brownish yellow; by tinfture of galls, the superfluous acid being saturated, of a chocolate brown j by Pruffian alkali, a brownish and red granular precipitate, diffufed through the whole liquor : that of copper by this alkali, being flaky ; and that of molybdena, not fo brown. By carbonated fixed alkali, whitish yellow; much of which is re-difsolved by the carbo- nic acid gas fet loofe. By pure ammoniac, lemon yellow. By carbonated ammoniac, dark yellow. But these solutions are precipitable neither by iron or zinc. This oxide is in- folubie in alkalies, either in the moist or dry way ; which folly distinguishes it from tungftenic oxide, which it resem- bles in colour. TELLURITE, or SYLVANITE. Klaproth, although he firft appears to have clearly afcertained the exiftence of this metal, modeftly gives the honour of the difcovery of it to Muller, and even to Bergman. Mr. Kirwan fir-t called it fylvanite, but Mr. K/aprstb denominated it tellurium. He difcovered it whillt analyfing the gold ore from Fatzebay, in Transylvania. It is one of the most volatile and fufible of the metals, except quickfilver, and is of a dark grey colour, inclining to red, and of confiderable metallic fplendor. It is femi-duclile and femi-malleable. Before the blow- pipe it burns with a blue flame with a gieen edge. When biokei ''•■"■ ' ■-'"• - :nt ieduc\ion, it 102 changes colour from purple to violet and then to blue. Sp, gr. 6,115. I1 readily unites to quickfilver and fulphur. It is foluble in nitric acid, yielding cryftals in the form of den- dritric aggregation; and in fulphuric acid, in the cold, in 100 times its weight of concentrated acid, yielding a beau- tiful crimson folution, which loses its colour by heat, or dilution with water. It is also diffolved in the nitro-muria- tic acid, and is precipitated from its folhtions, in a metallic ftate, by iron, zinc, tin, and even by muriate of tin; alfo by faline fulphurets, yielding sulphurized oxide of SYLVANITE. Its oxids are reduced by exposure to heat on a piece of charcoal, with a rapidity approaching to detonation. It amalgamates with mercury, and its precipitation by anti- mony ftows it is not that metal difguifed. The order of affinities of the oxide are not well determi- ned.-----Dr. Pearfon's Nomenclature, 1799. TITANITE was firft discovered to be a metallic fub- ftance by Klaproth, it having been before that confidered as a red fliorl. The same indefatigable chemist has discovered its exigence in menachanite, a fubftance firft noticed by Mr. M'Gregor, in the valley of Menachan, in Cornwall, in fmall black grains refembling gunpowder, Mr. Kirvian pointed out the lefcinblance between this fubftance and titanite. The oxide cf this metal, which is of a whitifh yellow, requires to be difoxidated to a ceitain degree to become foluble in ac ds. It is therefore treaied with pot-afh, du. ring which procefs it partes through various colours, red, blue, green, Sec. according to the quantity of oxygen it retains ; with which it even again fupplies itfelf whilst dry- ing, as is also the case with iron.-----Lowilz. Ann. it Chi. xxxIV. A fl-nder flick of tin bring placed in a solution of the MURIATE if titanite, the solution becomes fiift lowe- red and then cf amethyitine hue. Zinc thus produces firfta riolet, and then a deep indigo blue.' Gren. The folutions of titanite yield alkaline carbonate?, and in white flocks by the addition of alkalies. The pruffic acid precipitates it of a green colour accord- ing to Klaproth, but according to Lowitz of a dirty ycllovv- ifh brown. 103 On the authority of Lampadius, the order of attraftion ij, gallic, phosphoric, arfenic, oxalic, fulphuric, muriatic, nitric, and acetous acids.-----Ann. de Chi. xxvi. CHROME is a metallic fubftance, of a wbftifh grey, fhining, and very brittle; obtained by Vaoquelm from the mineral, called Siberian red lead. He obtained the chromic acid from this mineral by the following proceffes: By boiling ioo parts of this mineral with 300 of carbona- ted pot-ash, and 4000 of water, separating the lead and the alkali by weak nitric acid. Also by mixing 100 parts of muriatic acid, of Siberian red lead and of water, from which an infoluhle muriate of lead feparated ; the remaining mu- riatic acid being engaged by an oxide of filver, and precipi- tated by lime or cauftic alkali, in the form of horn filver, which leaves the acid. This cryftallizes in small long prifms of a ruby red colour; forming with mercury, a compound of a cinnabar red colour; with filver, a carmine red com- pound ; with lead, an orange yellow mineral; and with iron or tin, the solution of the acid becomes green. It yields part of its oxygen to muriatic acid, by which it oxyge- nates it, pafling itfelf to a green oxide . Journaldes Mines. xxxiv. 1798. Before the blow-pipe Chrome does not fufe, but becomes oxided; but with borax ii melts, and tinges that fait of an emerald green. Nitric acid afts on it only when boiled on it repeatedly, in a concentrated ftate, and in confiderable quantities. The acid is of a ruby- red, and contains about two-thirds cf it3 weight of oxygen, and on parting with a certain por- tion of oxygen, even to light, the oxide of chrome is formed, whch is cf a beautiful green.——Ann. de Chim* xxv. Vauquelin therefore concludes that the chromic is a true and diftinft acid, and that the radical or bafe of this acid is a peculiar metallic fubftance. The Sibtrian red lead ore may be confidered as a CHRO- MIATE of lead. It also forms chromiates with the earths and alkalies. From 72 parts of the ore in a ftrong heat in a crucible with charcoal, he obtained 43 of grey metallic featheied cryftals. From the beaut;ful emerald o-reen it the acid might !04r be a valuable addition to the pigments of the enamtller: and the oxide, from the tints it produces in combination with other metals, might become an useful ingredient in colours for painting : it would also be an excellent re-agent for the discovery of the lea6t portions of lead, silver, and mercury. The durability of its pigment may be inferred from the emerald of Peru not losing its colour, which it derives from this oxide, in the greatest heat. The emerald appears to be coloured by the oxide, and the ruby by the acid. Tassaert has not only found the chromic acid united to lead, but also to iron. Ann. de Chim. xxx. ARSENIC—Its natural colour is white, with a strong shade of blue, but it quickly tarnishes by exposure to the aii, becoming a pale yellow, and at last greyish black. Sp. gr. 8,310. It is brittle and not soluble in water. On burn- ing coals, it gives a low bluish white flame, an alliaceous smell, and white smoke, which holds an imperfecl oxide of arsenic, or the white arfenic of commerce. In close vessels, it sublimes without alteration, and crystallizes in trihedral pyramids, or octahedrons, of a brilliance resem- bling steel. This substance, which in general is called arsenic, is of a glittering whiteness, sometimes of a vitreous appearance; exciting an acrid taste on the tongue, and subliming with the same smell and smoke as the arsenic itself. It may be reduced to the metallic state by treating it with oils, soaps, or charcoals, in close vessels. Arsenic is often combined with metals in various ores, and is disengaged from them by calcination. It unites by fufion, with most of the metals ; those which were duct le, becoming thereby brittle; those which were difficult of fu- fion, flowing more easily; and those which were very fufi- ble, becoming refraftory. The yellow or red metals being also rendered white. The oxide is less volatile than the metal itself. If sub- limed by a strong fire in closed vessels, it becomes trans- parent like glass. The oxide iequires for its solution eighty times its weight of water at 12", and fifteen at boiling heat: and of alcohol seventy or eighty at boiling heat. Like the other metallic oxides, it is convertible into a metallic glass by a strong heat, and forms an opaque insoluble substance possessing metallic brilliancy 5 but unlike them, it is soluble 10$ in water, unites with metals, is volatile, and emits a strong odour. By its union with sulphur, either orpiment, or realgar is formed, the first being yellow, the latter being1 almost reppofed by the oppcfite characters of lime : they have alfo 115 frequently a greenifh caft, are inclined to a ftriated or flaty ftruclure, and to a luftre of the filky kind. Magnefia mixed with filex forms the silici-murite ; with lime and fome iron, calci-MURITE ; with alumine andiron, argillo-murite j and with a farther addition of filex and lime, chlorite ; by its combination with filex and alumine, are formed the talcs, and by the addition of oxide of iron, and carbonic acid, the various steatites.. The LAPis ollaris contains a fmall portion alio of the fluoric acid. The serpentines appear to refuk from its union with//** and iron; and by various intermixtures of carbonate of lime, are formed theASBESTUS, amianthus, and the suber-montanum, or corium-montanum. By fomewhat fimilar combinations are prpduced^alfo ami- anthinite, asbestinite, asbestoid, baikalite, with the shorlaceous, and glassy actinolyte and JADE ; in fome of which is alfo contained the fluoric acid. By its union with the boracic acid, alumine, and iron, is formed the ftone called boracite. Alumine or argil gives the fmooth, foft, and unctu- ous feel of clay in its mixtures with filex, when it exifts in a tenth part; but, with lime, not unlefs it exceeds the lime in quantity. Mixed with magnefia, and not exceeding a fifth part, it gives a difpofition to a flaty or lamellar ftruc- ture. From its admixture with filecious fand, are formed the va- rious CLAYS, FULLERS-EARTHS, L1THOMARGA, BOLES, marls, and colorific-earths, which are coloured by various metallic, vegetable, or bituminous particles. From its union With filex and iron, proceeds the Tripoli ; from its union with phofphoric acid, PHOSPHOLiTE; with filex, iron, and manganefe, is formed lfpidoliTE; and with the addition of magnefia, sappare ; and by combinations, in fome refpefts fimilar, mica, micarelle, and with the ad- dition of lime hornblende, schiller spar, wacjcen, MULLEN-STONE, KRAG-STOME, TRAP, TOAD-STONE, BASALT, CALP, ARGILLITE, SLATES, and NOVACULITE. Lampadius has difcovered that hornblende contains char- coal diffufed through it, and Mr. Kirwan fufpe&s that fome pitch ftones contain it. It is conje&ured that it may exift in other foflils, and caufe the peculiar earthy fmell, which we perceive by breathing upon ftones. With the coloured and bafer forts of clay are made TILES and BRICKS, and with a finer fort the different kinds of POTTERY. With the more pure and fat clays are formed TOBACCO-PIPES, and thofe finer clays which, in ftrong 116 fires, only undergo an incipient vitrification are employed for the fine PORCELAINS. SiLtx when moft pure, is termed rock crystal, and quartz ; its cryftals are the dodecaedron with triangular faces, or double hexedral pyramid with or without an inter- mediate prifm. From its mixtures with various propoitions of iron, lime, and alumine, refult the amethyst, topaz, SAPPHIRE, HYACINTH, GARNET, CHRYSOBERYL, and olivin. From its union with fhorlaceous aclinolyte, pro- ceeds the prasium ; and with alumine and iron, obsidian • and manganefe being added to thefe, the refult is**H0Ri,! W ith alumine, lime and iron, it forms the tourmalin and the prehnite ; and with the addition of manganefe, thu- MERstone. Combined with alumine, lime and water, it forms the zeolites ; and with barytes in the place of lime, the staurolite ; with alumine, blue fiilphur of iron, ful phate and carbonate of lime, lapis lazuli ; with nickel, iron, alumine, and lime, chrvsoprase ; with alumine and lime, vesuvian ; with alumine only, Shorlite; and with alumine and pot-afh, liucite. If this laft combination alfo hold oxide of iron and manganefe, rubellite is the refult ; but if iron only is added, opals, semi-opals, and pitch-stone. From the addition of lime to the com- bination juft mentioned, proceeds hyalite. From the va- rious intermixtures of alumine, and a fmall portion of iron, alfo proceed chalcedony with its varieties, cornelian, cat's-eve, onyx, mocha, agate, cucholong, and; the sardonyx ; and by the farther addition of a fmall por- tion Of lime, FLINT, HORN-STONE, PETRO-SILEX Or CHERT, JASPER, EGYPTIAN PEBBLE, PORCELANITE, HELIOTRO- Pium, woodstone, and elastic quartz are formed. From the more compound mixtures of- this fpecies of earth with alumine, magnefia, lime, and iron, are formed the felspars, and moon-s^one, and with a fmall porti- on of copper, the labradore stone. Nearly allied to thefe are petrilite, fklsite, red-stone, and sili- ceous spar. Agates are compofed of binary, ternary,. or more numerous combinations of calcedony, jafper, quartz," hornftone, £cc. Strontian is ranked as well as baryt, among the alka- lies, by Fourcroy.----Tabl. Synopt. 1800. It has been found in a ftate of Carbonate, in-a lead mine in Argylefhire, and near Boyra in Tranfylvania; and in a flate of sulphate in Freyberg, Syria, Hungary, and near Briftol. Jargonia. The only ftone of this genus* is the ftone called zircon, or Jargon of Ceylon. 117 Glycine, the newly difcovered earth of Vauquelim, is found to exift in the emerald of Peru, in combination with alumine, filiceous earth, lime, and oxide of chrome. The beryl, or aqua marine, alfo contains this earth with filex, alumine, lime, and oxide of iron. ■ ■ Annates de Chi- mie, xxvi. The ruby appears, by the analyfis of Vauquelin, to be a faline fubftance, compofed of two hafes, alumine, magne- fia, and the chromic acid. The difference of colour between the ruby and the emerald, both of which he has difcovered owe their colour to this acid, he attributes to the different degree of oxidation of their colouring matter, the red chro- mic acid, on parting with a portion of its oxygen, becoming green ; hence he fuppofes it to exift in a ruby, in the ftate of an acid, and in the emerald, in the ftate of an oxide.---- Journaldes Mines, xxxviii. By the analyfis of Vauquelin, it alfo appears that the chrysolite, which poffeffes all the external appearances of a ftonev is not truly of that clafs, but is a fait compofed of the phofphoric acid and lime.----Ann. de Chimie. xxvi. Klaproth having analyfed the apatite found it alfo to be a faline fubftance; containing, in the proportion of 45 to 55 of phofphoric acid and lime. The DIAMOND, though confidered as a precious ftone, has long Jieen known to be of an inflammable fubftance, and is now believed to be the fubftance called carbon, exifting in its moft fimple ftate, and in a cryftallized form. A mineral fubftance brought from S-ydney Cove, was fuppofed to contain a new fpecies of earth, which was there- fore termed sydneian earth ; but Mr. Hatchett having analyfed this fubftance, fays, " I do not hefitate to affert this mineral does not contain any primitive earth or fubftance, poffeffing the properties afcribed to it, and confequently that the Sydneian genus, in future, muft be omitted in the mineral fyH^."----Phil. Tranf. 1798. The ftone called the corundum stone, and from its hardnefs, adamantine spar, was alfo fuppofed to con- tain a new earth, which was therefore termed CORUNDa. Mr. Klaprotlf s firft analyfis of this mineral, gave filex 31,5. Iron and nickel 00,05, and adamantine earth, 68.. But by a fubfequent analyfis, by Mr- Klaproth, of this mineral, he found that it contained alumine, from 84 to 89. Silex 5,5. to 6,5. Oxide of iron from i,a to 7,5, and no new earth of any kind. Aggregated stones. By the intermixture of quartz, felfpar, and mica, is formed granite ; and by the addi- 118 tion of hornblende, sienite ; and by various triple combi- nat.ons of thefe fubftances with fhorl, ferpentine, fteatkes and garnites, granitinE; quartz, mica and garnet com - pole the ftone called norka or murkstein. The dupli- cate ague, ates, Mr. Kirwan calls gramitell; that of quartz and mica the Swedes call stell-stein, Avantu- rine may be confidered as of this fpecies ; hornblende 2nd mica foim the grun-stein, quartz and fteatites, the saxum molare ; and capillary fhoots of fhorl in quartz form the kair-stoke of the Geimans. By gramlites are meant granites compofed of more than three conftituent parts. Gneiss is formed like granite, of quartz, mica, and f elf par, but is of a thick flaty or fibrous texture, not granu- lar. Shistose mica is compofed of quartz and mica, and is of a fhiftofe or flaty texture, but contains moie mica than gneifs. Porphyry is any ftone which in a filiceous, argillaceous, muriatic, or calcareous ground conta.ns f'cat- tered fpots of felfpar, vifihle to the naked eye. It may alfo contain quartz, hornblende, and mica. Accotdngto the ground it is named filiceous porphyry, Sec. Amyg- daloid is a ftone formed by elliptical mafles of quartz, lithomarga, fieatites, hornblende, Sec. in a ground of trap, mullen, krag, &c Pudding stones are formed by filiceous pebbles cemented together by a fubftance of a fimi- lar nature, or by a ferruginous compound. Sandstones are formed by imall grains of flint, quartz, &c. in aground of calcareous, filiceous, argillaceous, or ferruginous kind. Sometimes thefe are cryftallized, as in the sandstone of Fontainbleau. When they contain mica, they are termed micaceous sand stones. Stones that have round protuberances of a different fubftance from the com- mon mafs are called variolitks. Stones not really por- phyries, but approaching thereto, may be called porphy- ROins, and on the fame principle is the term granitoid employed. Thofe are termed mixed earths, in which the different conftituent parts are vifible to the naked eye. Dkrivatives are earths or ftones refulting from the coalition of ftones and earths of different fpecies, the different conftituents not being diftinct to the naked eye. Loam is clay with a fuperabundance of fand. Mould is loam mixed with the decayed remains of animals and vegetables. Bergman relates, that in fome of the mountains of Nor- way, which confift of" an argillaceous pudding-ftone, the filiceous pebbles it contains, are obferved to be comprefled^ to the thickuefs of a fourth of an inch, in the lower part of* 119 the mountain, but no increafe in fize and roundnefs in pro- portion as their fituation is higher. VOLCANIC PRODUCTIONS.—The liquified matter iffuing from volcanos is in general called lava. This is either vitreous, or cellular, or compacl, or in the ftate of enamel. Befides the lava itfelf, fcoria, fiaggs, afhes, and fand, are produced by the eruptions of volcanos. PouzzOla- Na, a fubftance compofed of filex, alumine, lime and iron; terrass and tufas, confiding nearly of the fame principles as the pouzzolana ; Piperino, a concretion of volcanic alhes, a kind of breccia; and pumice stone are alfo produced by volcanic fires. Pseudo volcanos emit fmoke like volcanos, and fometimes flame, but never lava. Widely different are the opinions of chemifts, refpecling the formation of various lapideous fubftances, and of the caufes of the vaft changes which have evidently taken place in this globe. Some, the Plutonifis, contend that thefe are entirely the confequences of the aftion of fire, on the ele- mentary fubftances of which our globe is compofed. While on the other hand the Neptunifts attribute the fame effects entirely to the powerful action of water. Basaltes are columnar maffes of • regular polygon ftones, moft commonly hexagonal, frequently pentagonal, difcovered in various parts of the world, particularly in the iiluid of Staffa, Icolmkill, &c. in the weftern part of Scot- land, the oppofite fliores of Ireland, where they form a tract called the Giant's Caufeway, Norway, Italy, &c. Mr. Kirwan, who contends for the Neptunian origin of bafalt, fhorls, &c. obferves that the heat communicated by volcanic fire, fcarcely ever equals no" and that not only fhorls, which are fufible at 950 and garnets, are rejected from volcanos, 1111 fufed 3 but even calcareous and flu or fpars, with their tranfparency unimpaired. Thefe, he fup- pofes, undoubtedly to have pre-exifted in the rocks or mo- ther ftones, before the eruption. In confirmation of his 'opinion refpecting the aqueous origin of bafalt, he remarks, that this fubftance is converted by fire, into a moft beauti- ful black glafs, and that Mr. Chaptal has even converted certain kinds of lava into glafs; which he employed in calling bottles. 120 *Dr. Beddoes believes the origin of bafaltes, from fubter- raneous fufion, to be thoroughly eftablifhed by various authors, notwithftanding Mr. Werner's recent objections; he alfo believes there exifts an affinity between granites and bafaltes ; that granite lavas are indeed granite rocks fufed, and that they have cracked like the bafalte en tables,—. Phil. Tranf. 1791. Dr. Hutton, in his Theory of the Earth, differing from Mr. Kirwan, conceived that whinftone or bafaltes, &c. at- tained their prefent pofif.on in a ftate of igneous, fufion j but the converfion of whinftone, &c by the heat of furna- ces, inu glafs, was fuppofed to refute the Doctor's hypothe- fis ; fince, his opponents faid, if fire had been the agent, glafs, and not whinftone would have been formed. Sir James Hall, believing that the mafs might, by flow refrigeration in the bowels of the earth, have undergone a change fimilar to that of glafs into Reaumur's porcelain; and have, by cryftallization, loft the vitreous, and affumed the ftony character, fufed feven different fpecies of whin- ftone, and by rapid cooling reduced them to a ftate of per- fect glafs. This glafs he again fufed, then reduced it to about 280 Wedgwood, in which temperature he kept it for fome hours, and on allowing it to cool, the character of glafs w3s loft, and by cryftallization they had all affumed that of an original whinftone.----Nicholfons Journal, Oil. 1799. Mr. Kirwan has, however, fince offered fome ingenious objections to the inferences drawn from thefe experiments, as to the high degrees of heat attributed to volcanos, ac- knowledging the difcovery of the caufe of the ftony appear- ances which lavas exhibit after cooling to be a difcovery of great importance to geology.1----Philof. Journal, 1800. Dr. Samuel Mitchell, of New-York, obferved in a fliff loam feveral bodies of a pentagonal figure, formed from a Folid circular mafs of argillaceous iron ore, of about two feet and five inches in breadth, and four inches in thicknefs. In the natural fracture of the ftone, the fragments took up- on themfelves thefe regular forms, very much refembling bafaltes; and like bafaltes, though figured, they evidently were not cryftallized, for they are as perfe&ly ferruginous and opaque as any argillaceous iron ore whatever. Do not thefe fpecimens, the Doctor fays, go very far towards deci- ding the difpute about the igneous or aqueous origin of ba- faltes ? They fupport, he thinks, their Neptunian origin, and prove that argillaceous iron ore, which nobody has fup- pofed to be a volcanic production, can take on a bafaltic fi- gure.——-Nicholfon's Journal, Feb. 1799. 121 Dr. Garnet accounts for the origin of basaltES, by fuppofing, that a quantity of pyrites very rich in iron, along with argillaceous and other earths, has been fufed into a thin liquid mafs by the fire of a volcano. On an eruption ta- king place, that part of the lava or liquid matter, which is thrown out by the expanfive force of the vapours, or fire, and brought into contact with the air, cools too fuddenly to admit of any regular form, but that which remains quiet within the bowels of the mountain, will cool very flowly, and be left without interruption to form cryftals, or rather, by the gradual diminution of its bulk, to fplit into regular pillars, like ftarch when it is drying.-»—Tour to the Wefiern Iflands of Scotland. Mr. Baume, by a feries of ingenious experiments, dif- covered that clays may be produced by the action of ful- phuric acid on vitrified fubftances. Mr. Ferber applied this fact to the grand operations of nature on the matters eject- ed by volcanos ; he difcovered a fine white argillaceous mat- ter in the hollow part of vitrified lava, evidently produced by the action of the fulphuric acid. Hence it appears that thofe fubftances which have, by the action of fire, been ren- dered otherwife intractable, again become, by the action of the fulphuric acid, fubfervient to vegetable life. ■ Ferber''s Letters. It is however obferved by Mr. Spallanzani, that although vitrified fubftances are thus changed by the action of ful- phuric acid; the acid does not convert the vitrified fubftance to alumine, but merely difengages it.«—■Voyage to the Two Sicilies-. >C" OF THE PRIMEVAL STATE OF THE EARTH, AND its subsequent changes. Mr. Kirwan fuppofes the fuperficial parts of the globe to have been originally in a foft liquid ftate, proceeding from folution in water heated at leaft to 33', and poflibly much higher. This menftruum muft have held in folution all the different earths, the metallic, and femi-metallic, the faline, and the inflammable fubftances; being a more complex men- 122 flruum than has ever fince exifted. In this fluid, its folid contents coalefced and cryftallized, according to the laws of elective attraction ; quartz, felfpar, and mica, conftituting granite, gneifs, Sec. he fuppofes to be firft depofited, with Various metallic fubftances, particularly iron. In other tracts, according to the predominant proportion of the ingredients, were formed filiceous Jhifius, porphyries, jafpers, Sec. with argillites, hornblende, Jlates, ferpentines, and other prime- tvalftones; and the metallic fubftances meeting and combi- ning with fulphur, formed the pyritous fubftances and/»/. phurated ores. With the fulphur alfo petrol would com- bine and enter into combination. By this cryftallization of thefe immenfe maffes, a prodigious quantity of heat muft have been generated, and increafed by the decompofition of the water, intercepted in the precipitated ferruginous parti- cles, and by the difengagement of inflammable air, even to incandefcence ; the oxygen uniting with the inflammable air, and burfting into flame. This ftupendous conflagrati- on, fupported alfo by the fulphurated, carbonic and bitumi- nous fubftances, muft have rent and fplit, to an unknown extent, the folid balls on which the chaotic fluid refted. From the heated chaotic fluid muft have been extricated the oxygen and mephitic airs, which gradually formed the atmof- phere. From the union of oxygen with the ignited carbon, proceeded the carbonic acid, or in Mr. Kirwan's words, the fixed air, the abforption of which, as the chaotic fluid cooled, occafioned the cryftallization and depofition of the ralcareoxs earth.* The immenfe maffes, concreted and depofited by the combination and cryftallization of the feve- ral earths on the nucleus of the globe, formed the primitive mountains. The formation of plains took place from the fubfequent depofition in the internals of diffant mountains, of matters lefs difpofed to cryftallize; fuch were argillace- ous and ferruginous particles, and fuch particles of other earths, as were too diftant from each other's fphere of at- traction to concrete into ciyftals. The level of the antient ocean being lowered to the depth of 8500 or 9000 feet, then and not before, it began to he peopled by fifh. That the creation of fifh was fubfequent to the emerfion of the tracts juft mentioned, he thinks, is proved, by no marine fhells * The formation of fixed air being fubfequent to the formation of the primeval ilones, he thinks, appears from the calcareous earth being found in the compofition of primeval ftones, ijv a cauftic ftate. r23 or petrifactions being found in tracts elevated above the height of 9000 feet, and reciprocally, of the mountains containing petrifactions, none reaches to the height of 8600 feet. After this elevated tract of the globe had been unco- vered by the retreat of the fea to its bed, there is no realbn to believe it remained long diverted of vegetables, or unpeo- pled by animals; being in every refpect fitted to receive them. This retreat of the fea, from the lower parts of our prefent continent, was not effected, he fuppofes, until the lapfe of feveral centuries ; this, he thinks, is proved by the vaft ac- cumulated heaps of foffil fhells, in inland fituations, and the difcovery of trees and vegetables in great depths, of our modern continents ; and from the appearance of ftratified mountains formed by gradual depofition ; and thus entomb- ing fifh, fhells, wood, &c. The retreat of the fea continu- ed probably until a few centuries before the deluge, which he conceives to have originated in and proceeded from the great ibuthern ocean below the equator, and thence to have rufhed on the northern hemifphere, fpread over the arctic re- gion, and then to have defcended fouthwards. During this elemental conflict, he fuppofes the carbonic and bituminous matter muft have run into maffes no longer fufpenfible in wa- ter, and have formed ftrata of coal; the calces of ironr gradually reduced by the contact of bitumen and precipita- ted with the argillaceous and filiceous particles, forming bafaltic maff'er, which fplit into columns by deficcation. The eruption of fixed or oxygen air would form cavities ir» which, by fubfequent infiltration, calcedonies, zeolytes, oli- vins, fpars, Sec. might be formed. This fyftem, Mr. Kirwan fays, agrees with the geologi- cal facts related by Mofes, not only in fubftance but in the order of their fucceflion.-----Geological Effays, 1799. It is remarked by Mr. Jamefon, that in the Shetland Iflands, the eaft fide is low, but the weft, lofty, rugged, and broken, and many of the mountains are more fteep on the weft, than on the eaft fide. Upon examining other part* of Scotland, England, Norway, &c. fimilar phenomena prefent themfelves.—The rivers alfo generally run from weft to eaft.—Hills, he remarks, all run in the longed di- rection of the iflands in which they are placed. Miner-a- logy of the Shetland Iflands* 124 OF VEGETABLE SUBSTANCES. VEGETABLE SUBSTANCES appear to derive their chief nourifhment from water, which, on its reception into the plant is reduced to its firft principles, hydrogen and oxy- gen ; the hydrogen becoming an effential principle of the ve- getable ; and conftituting the greater proportion in the com- pofition of refins, oils and mucilage. The oxygen is partly employed in producing vegetable acids, &c. and partly ex- pelled by tranfpiration through the pores of the plant: its feparation is evidently accelerated by the action of light; fince during night plants chiefly give out carbonic acid gas. The air is ufeful in vegetation, not only as a vehicle for water, caloric and light, but from its yielding oxygen, which enters into the plant itfelf, and which alfo combines with the carbon and hydrogen it meets with on the furface of the plants ; furnifhing alfo a portion of carbonic acid, from which nourifhment is derived in a high degree. The carbonic acid thus abforbed is decompofed, its carbon is de- pofited in the plant, aiding the formation of the vegetable fibre, whilft its oxygen is tranfpired. Thus alfo carbonated hydrogen promotes vegetation.. M. Sauffure finds that plants, bke animals, form carbonic acid, with the affiftance of the oxygen of the atmofphere, the acid being often decompofed as faft as it is formed. Light, he obferves, promotes vege- tation by decompofing the acid ; and therefore that propor- tion of the acid wh;ch favours vegetation during the influ- ence of the fun, injures it during the night. Vegetables deprived of the carbonic acid they form are injured in their growth ; but lefs fo in oxygen gas, becaufe they produce in that cafe more than is deftroyed. M. Sauffure has alfo obferved the formation of carbonic acid gas, by the oxygen of the atmofphere uniting with carbon yielded by germina- ting feeds.-----Journal des Chemie, Jan. i8qo. Nitrogen gas, fo unfriendly to man, appears to be rapidly abforbed by vegetables. Light is certainly neceffary to vegetable life, it ferving as a ftiinulus, and being alfo a powerful agent in decompofing the various nutritive principles; and particularly in fepara- ting the oxygen gas from the fubftances imbibed, whilft their bafes become fixed in the plant. Light has beeft fuppofed to occafion the green colour of vegetables, plants growing in the dark being white, when they ars faid to be etiolated. But Ftn Humboldt finding 125 plants green which have grown in the dark, but in imflam- mable or mephitic gafes, attributes the verdure of plants to hydrogen and azote in certain proportions.——Experiments by V. Humboldt. A fenfible production of heat is difcoverable in vegeta- bles, fo as fometimes to exceedthat of the atmofphere. This heat is, undoubtedly, an effect of the fixation and concreti- on of thofe matters which form the food of plants. Vegetables appear to be endued withdigeftive organs, and to poffefs the power of digefting and affimilating thofe fub- ftances, which are taken up by their abforbents, and which are congenial to their nature. They alfo are capable, not only of throwing off thofe fubftances which cannot be afli- milated by them, but even fuch of their principles as may exift in excefs. Thus oxygen is emitted both from land and aquatic plants, in very confiderable quantity, during their expofure to the action of light; and by this continual emif- fion of vital air, is the lofs repaired which is occafioned by refpiration, combuftion, fermentation, and putrefaction* Plants likewife emit a very confiderable quantity of water in the form of vapour. I. The sap is that fluid which is formed by the elabora- tion of the various fubftances which are taken up as pabula by the plant. It is the general humour of vegetables, as the blood is of animals, and from this are fecreted the proper juices of different vegetables. The faps of the elm, the beech, the fervice, the birch, and the mulberry-trees appear to differ confiderably in tlieir compofition j but in general they contain in much water, gum, fugar, extractive matter, tannin, carbonic acid, ace- tous acid, and falts with bafis of pot-afh.-----Fourcroy, 1800. II. Mucilage is a vifcious matter, which exifts in moft feeds and young plants, in fo great a quantity, that they are almoft refolvable into it- It alfo forms the bafis of the proper juices of the plants: and fometimes as in cuphorbi- um, celandine, Sec. it is combined with matters infolubie in water, which it keeps fufpended in the form of an emulfion. It is fometimes found almoft entirely alone, as in mallows, linfeed, &c. Sometimes, k is united with fugar, and at other times with oil, forming the fat oils. It fometimes conftitutes the permanent ftate of the plant, as in the con- ferva, lichens, champignons, &c. The characters of mucilage are:—1, Infipidity. 2, So- lubility in water. 3, Insolubility in alcohol.- 4, Coagula- 126 tion by the action of weak acids and metallic folutions. 5, The emiflion of a confiderable quantity of carbonic acid, when expofed to the action of the fire, and being converted into a coal without exhibiting any flame. It likewife, when diluted with water, readily paffes to the acid ferment- ation ; and by diflillation yields what is termed the pyro- mucous acid. Its formation feems almoft independent of light. Mucilage may be changed into oxalic acid by the nitrie, and into the citric, by the muriatic acid.-----Vauquelin. III. Gum exudes from different parts, but chiefly from the trunks and branches of trees. It is generally fuppofed to be only infpiffated mucilage. It appears to confift of oxygen, hydrogen, carbon, nitrogen, and lime, with a little phofphoric acid; differing from fugar, not only in containing lei's oxygen, but alfo by its combi- nation wi'h nitrogen and \\me.——-Cruikftbank. IV. Oils. The oily principle appears to be the fame in all oils; but is combined with mucilage in fixed, and aroma in the volatile. 1. Fixed, or fat oils, are obtained from feeds, or kernels, by expreflion in proper facks between metallic plates. The feparation is aided generally by heat, and when heat is not employed the oil is faid to be cold drawn. They are info- lubie in alcohol or water, and are generally mild. They all congeal at certain degrees of diminution of heat, and are volatilized at a degree of heat beyond that of boiling water ; and, when volatilized, take fire by the contact of an ignited body. By diflillation they afford phlegm, an acid, confequently oxygen, a fluid, or light oil, much hydro-carbonate ga3, with carbonic acid gas, and a coally refidue which affords no alkali. The volatile oils afford more hydrogen gas, and the fixed more carbonic acid gas ; this laft depending on the mucilage. Oil eafily combines with oxygen. This combination is either flow or rapid. In the firft cafe, rancidity is the con- fequence, and combuftion in the latter. It feems, more ftrictly fpeaking;, that when the oxygen combines with the mucilage in the oil, it forms rancid Oil, but that when it unites with the oil itfelf, drying oil is formed. The rancidity of oils appears to be an effect analogous to the ox- idation of metals; and the proof of its being produced by a change in the mucilage is derived from this circumftance, that if the mucilage be feparated from the oil, by ftrong 127 agitation in water, the oil may be preferved for a long time without any change. If the product of the combuftion of oil be collected, much water is obtained ; the hydrogen and the oxygen, which the oil contained, uniting and forming that fluid. Accord- ing to Chaptal, a pound of oil of olives contains 12 oz. 5 dwts. 5 grains of carbon, and 3 oz. 2 dwts, and 67 grains of hydrogen. The procefs by which oil is rendered drying, ftiows its dependence on the combination of oxygen with the oil it- felf, fince nothing more is required than to boil oil with metallic oxides ; during which procefs, a fubftance is dif- engaged which fwims at the top, and appears to be fimple mucilage. The oxides of lead, bifmuth and mercury, thus combi- ning readily with oils, become the bafis of certain plas- ters and ointments. But Deyeux obferves, that plaf- ters made with linfeed oil are moft foft and pliant. This difference he fuppofes to arife from the mucilaginous mat- ter in the linfeed oil; obferving alfo, that olive oil boiled with faenugreek or linfeed, acquires the properties of linfeed oil, it being his opinion that it is ihe mucilage which ren- ders certain oils drying.----Annales de Chemie, 1800. If oil is burnt without a fufficient accefs of oxygen a foot is formed, called lamp-black. The fixed oils unite with fugar, alfo with the acids. They may by certain media be intimately mingled with wa- ter, when they form a milky white fluid called an emulfion. With the fulphuric acid they form a mafs foluble in alcohol and water. With the nitric they turn black, and fuch as are drying inflame at the time of combination. The muri- atic forms a faponaceous mafs with them, and the oxy-mu- riatic thickens them. Thefe maffes have been called acid foaps. The alkalies alfo combine with the fixed oils, and form soaps, by which oils are rendered mifcible with water. The foaps generally made in England are, 1. White foap, from tallow and a ley of foda. 2. Mottled Soap, from tal- low, kitchen-ftuff and foda. 3. Yellow hard foap, with tallow, rofin and foda. 4. Soft foap, from whale or fifh oil with pot-afh, the ley of which is not drawn off; and when it is combined, a fmall quantity of tallow is added, which forms the white fpots. Sir John Dalrymple propofed to ufe the mufcular fibres of fifh, in a certain proportion with tallow, to make hard foap, and to fubftitute it for oil, in the manufacture of foft I2S foap. But by experiments made to determine the value of this propofal, it appears, that in making hard foap, the greater part of the fifhy matter was ufelefs, being nearly in a gelatinous ftate ; and that it feparates from the tallow, fi> that the fifh and tallow will not combine. In attempting to make foft foap, the precarioufnefs of the refult, and its af- fording little or no faving, renders it unworthy of attenti- on.-----R. Jamefon. Nicholfon's Journal, 1799. By mixing oil with lime water, an acid folution of lime, folutions of the fulphates of magnefia, or of alumine, or of the muriate of baryt, an earthy soap, either mag. nefian, aluminous, barytie, Sec. is formed. The fat oils perfectly diffolve fulphur, and form a reddifh balfam, of a difagreeable odour, called balsam of sul- phur. They alfo diffolve phofphorus. 2. Volatile or effential oils are foluble in alcohol. They vary in their colour, confidence, odour, &c. and are ob- tained chiefly by diflillation. They abforb oxygen with greater facility than fixed oils, acquiring colour and conflu- ence, and pafling to the ftate of refin ; depofiting at the fame time needle-formed cryftals, which have by fome been fup- pofed to be camphor. Water actually diffolves a part of the effential oils, re- ceiving both tafte and fmell on being diftilled from the plant, as appears in the distilled waters. The nitric, fulphuric, and oxy-muriatic acids, are fpon deprived of their oxygen by the ethereal oils, which are thereby converted to refins. If two parts of oil of turpentine, and one of ftrong ful- phuric acid, be quickly ftirred together with a glafs rod, and a little concentrated nitiic acid be added, a fudden inflam- mation takes place. With alkalies the ethereal oils form » foap called effential oily foaps. They alfo diffolve fulphur.. They contain much hydrogen. V. Camphor is a white concrete cryftalline fubftance, which, though chiefly obtained from a fpecies of laurel, is find to exft in all odoriferous vegetables. It has a ftrong fmell and tafte, is foluble in alcohol, and in acids without decompofition. With a gentle heat it rifes unaltered; if ignited, it burns with a white flame, leaving no refidue. It is not folu'le in water, but communicates its fmell to that fiuid. Alkalies do not unite with it, but fulphur does by fufion in a gentle heat, or by the alkaline fulphuret. It is capable of cryftallization either by fublimation, or precipi- tation. It appears to be a volatile oil, rendered concrete by carbon; and, treated with nitric acid, yields its peculi- ar acid. 129 Romieu has obferved that fmall pieces of camphor obtain a rotatory motion, when placed on water, in a glafs, the motion ceafing if the water be touched by a conductor of electricity, but continuing if touched by an electric per fe. It does not turn upon hot water.-----Bergen. Prevoft and Venturi have remarked the curious appear- ances oblervable from the floating of camphor and other o- dorant bodies on water, under different circumftances. Annales de Chimie, xix. It appears that thefe phenomena proceed from jets of ef- fential oil thrown out with rapidity from thefe bodies, which make them move on the water,—Brugnatelli. VI. Resins appear to be oils rendered concrete by their combination with oxygen. They appear to be volatile oils oxygenated and in part dif-hydrogenated——Fourcroy, 1800. They are inflammable, and yield much foot, during their combuftion ; are foluble in alcohol and in oils, but not in water. They are generally lefs fweet than the balfams, and afford more volatile oil, but no acid by diflillation. Among the refins may be placed maftich, fandarach, Sec. Bouillon la Grange obferves that sena contains, befide* extractive matter and a gum, both refolvable into calcareous earths, and fimilar fubftances, a fubftance only wanting a portion of oxygen to make it a perfect refin. This it acquires by boiling and then becomes draftic. Hence he recom- mends the cold fnfufion, and not mixing it with acids or a- ny other fubftance which may fupply it with oxygen. Ann. de Chi. xxm. Tar is feparated from pine, and Scotch firs, in tar fur- naces, and when infpiffa:ed it becomes black pitch. The turpentines appear to be refins containing volatile oil. VII. Gum resins appear to be a natural mixture of mu- cilage and refin. They are partly foluble in water, and part- ly in alcohol, and render water turbid in which they are boiled. Under this head may be placed fcammony, gum gut- ta, affafetida, aloes, gum ammoniac, Sec. Some gum refins, are cleared by art of their extractive principle, for the purpofe of applying them to various ufes. •Such is the intention, in the procefs for making birdlime. Refins diffolved in fixed oils form the fat or oily varnifh; in volatile oils the effential varnifh ; and in alcohol the fpirit varnifh. VIII. Caoutchouc, called the elaftic gum, may alfo be placed here. The nitric ether diffolves this gum. If placed in contact with a volatile oil, fuch as that of turpen- tine, it fwells, foftens, and becomes very pafty, and may, ISO in this ftate, be applied as a varnifh. A mixture of volatile oil and alcohol forms a varnifh which dries more fpeedily i-infeea oil alfo, by long digefting on the oxides of lead, af." tords a pellicle of confiderable firmnefs ; tranfparent, won- dertully elaftic and exteniible, and burning like elaftic gum ii. pound of this oil, fpread on a ftone and expofed to the air for fix or feven months, acquired almoft all the proper- ties of elaftic gum-----Chaptal. * V IX. Balsams are fubftances containinga principle which does not exift in refins, and which combining with oxygen forms an acid, while the oil, faturated alfo with oxyL' rorms the refinous part, which is therefore found united with iS^fit:in this clafs n,ay be *,aced **** *p3 Fje-cula of vegetables appears to be only a flight al- r o„„fnracagej it differing from that fubftance" only in being mfoluble in cold water, in which liquid it fall! with wonderful qu.cknefs. If it be put into hot water, it torms a mucilage, and refumes all its- characters. It feems Toextralr^h'f13 &TP\ * ,muCilaSe' dePrived °f Cal°^ La iff ? ■ he faECula' the Plant muft bebruifed or ground, and d.ffufed i„ water ; and the faecula, which is at firft fcf! pended ,n that fluid, falls to the bottom. Thus is obtained *£?"LJkur\Ca-fa?a> fW* &c« In obtaining ftarch, the extiacW and glutinous Pa: ts are deftroyed by fermentation, tne fxcula or ftarch precipitating purer and whiter. Nitric acid converts ftarch into oxalic and malic acids. There are alio coloured facula, fuch as iudigo. XI Vegetable gluten. This has been called the vegeto-animalfubfiance, from its properties refembling thofe or animal fubftances. It is more particularly obtained from ed\SrhTe0US Jeget3bJeS-, -T° PFOCure '** a Pafte is f°™- edvvith flour and water, which is kneaded and wrought in ™L ?'* ,underwate'' t'"'1 it no longer communicates any colour to that fluid. The fubftance which then remains l the hand ,s tenacious, dudile, and contraftile^ becoming Z7,?1 Tn adhe[We> 3S " dlieS- Duii»S the °P^tion ive ZZ s to the.b,ottom of ,he watei>and the «t™a- ive matter remains in folution. fmJ!iegTfl,tinAUS-matt-eremits a vei-y cha'aaeriftic animal heat ; Jc M ,S,,n,1P,dj and on b^ng dried in a gentle heat it refembles glue, and breaks fhort like that fubftance. }'L a f t°" burnir* COa,S' jt curls "P> and burns like an animal fubftance. By diflillation it affords the car- bonate of ammoniac and /hew* in feveral inflates a very secided animal character.. f 131 Frefh made gluten, expofed to the air, readily putrifies, and when it has retained a fmall quantity of ftarch, this laft partes to the acid fermentation and retards the putrefaction of the gluten : in this way a ftate is produced refembling that of cheefe. Cold water does not attack this glutinous part; but if it be boiled with this fluid, it lofes its extenfibility and adhe- five quality: it alfo lofes its elafticity and glutinous quali- ty by drying. Alkalies diffolve it, by the afliftance of a boil- ing heat, and it is precipitated by acids, but deprived of its elafticity. The nitric acid diffolves it, with activity, emitting at firft the nitrogen gas, as when an animal fubftance is employ- ed. This is followed by an emiffion of nitrous gas, and the refidue affords by evaporation, the oxalic acid in cry- ftals. The fulphuric and muriatic acids likewife diffolve it, and falts with bafe of ammonia, may be obtained from the com- binations. Diffolved repeatedly in vegetable acids, and precipitated by alkalies, it is brought to the ftate of faecula ; and if vi- negar be diftilled from it, it is reduced to the ftate of muci- lage. It is to this gluten, that wheat owes its property of ma- king a good pafte with water, and the facility with which it rifes to form bread. This gluten is fometimes deftroyed by the fermentation of flour, by whii;h change it is render- ed incapable of rifing and forming good bread. It exifts in lefs quantity in the flour of other corn, but is a conftituent part of many other plants, particularly of the fungi. Its principles appear to be carbon, hydrogen, nitro- gen, phofphorus, and oxygen. Farina, or flour, therefore is compofed of three princi- ples, the amylaceous, or ftarch, or facula, the animal or glutinous principle, and the faccharine principle. XII. Sugar is a true effential fait, of a peculiar nature, a conftituent part of vegetables; it may be extracted from a number of plants, as the maple, birch, wheat, corn, beet, parfnips, grapes, &c. by digefting in alcohol. This fluid diffolves the fugar, and leaves the extractive matter untouch- ed, which falls to the bottom. The fugar generally ufed, proceeds from the fugar-cane,- arundo faccharifera. The juice of the cane is obtained by expreffion, and boiled repeatedly with wood-afhes, and lime, to part the acid, which would prevent the fugar from coagu- lating, until it acquires a fyrupy confiftence. It is then far- 132 ther concentrated by boiling with alum and lime, and the thinner fyrup, or me lasses, or treacle, allowed to fe- parate from the fugar, which in this ftate is called clayed sugar. This fugar fuffers then a farther refinement, by boiling with lime and with bullocks blood, which latter, coagulating by heat, involves and feparates moft of the fo- reign matters it contains, thus producing its clarification when it is called refined or loaf sugar. If allowed' to cryftallize, it will form tetrahedral flattened prifms, the fmaller lateral furfaces being fometimes compofed of two joining in an obtufe angle ; the fummits dihedral, being J truncated on two fides, it is then called fugar candy. 1 It may be converted by the nitric acid into the oxalic, and by fermentation into acetic acid. The juice of the fugar maple (acer faccharinum) yields it very plentifully. The carrot, and the beta cycla altifs, yield fugar in confi- derable quantity. The water remaining after obtaining ftarch, alfo contains a large quantity of fugar.——.Profeffor Jacquin and Dr. Pefchiere. Manna, which is fugar under another form, is fecreted and exudes from feveral vegetables, from the pine, the fir, the maple, the oak, the juniper, the fig, the willow, the I olive, Sec. but the afh, the larch, and the alhagi, afford it in the largeft quantities. From the ingenious inquiries of Mr. Cruikfhank, it ap- pears that, j. fugar is a pure vegetable oxide, confifting of carbon, hydrogen, and oxygen. 2. Sugar of milk differs only in containing more oxygen, and much lefs carbon. 3. Gum differs alfo in containing lime and azote. 4. Vegeta- ble farina cannot be converted into faccharine matter, with- ■ out the joint action of oxygen and water, the firft being ab- j forbed, the latter decompofed. 5. Sugar deprived of its \ oxygen, lo.es its characterise properties, appears fomewhat j like a gum, and is no longer fufceptible of the vinous fer- j mentation. 6. Neither vegetable nor animal mucilage, in ; their pure flare., are fufceptible of this procefs.----Expe- riments on Sugar. W. Cruikfhank. XIII. Albuminous -~.^ner of vegetables is obtained by filtering the exprefled juice of creffes, white cabbage, Sec. and placing it in a phial in boiling water when it depofits it in a floculent form. This matter refembles the white of eggs ; it is foluble in cold water and coagulates with heat or fpirit of wine, the coagulum being infolubie. Alkalies diffolve it, 1 <*f 1 oa XIV. Vegetable acids have all a compound bafis. Every one have carbon and hydrogen. The variety in their habitudes and properties proceed from the different propor- tion of thefe principles, and of oxygen, in each particular acid. We can decompofe them all, but cannot compound any one.' Gren. First, Vegetable acids ready formed, and obtained by very fimple proceffes. i. The citric acid, or the acid of lemons. This is obtained in a concrete ftate, by faturating the juice of le- mons with powdered chalk ; with which it forms a difficult- ly foluble fait, citrate of lime, which is to be wafhed with warm water, and then a fufficient quantity, previoufly afcertained, of fulphuric acid, to faturate the chalk em- ployed, is to to be added, then boiled for fome minutes, with ten parts of water, and then filtered: The fulphate of lime remains on the filtre, and the fluid, by evaporation, will yield the crystallized citric acid, which may be freed from the remaining gypfum. Its cryftals are octa- hedral prifms, truncated on their folid angles. It feems to be one of the ftrongeft of the vegetable acids j it is not converted by the nitric acid into the oxalic acid. It acts on feveral metallic fubftances by the aid of water, and forms citrates with the alkalies and earths. By expofing the juice of lemons to a freezing cold, the water it contains will be frozen, and the acid remain in a liquid ftate, highly concentrated. M. Brugnatelli, obtained citric acid pure, by well ftraining it through linen cloth, then mixing it with fpirits of wine, and, after ftanding fome days, filtering it through paper; the pure citric acid pafling through, and the fli- my matter being left on the paper. ■ Ann. de Cbim. xxn. 2. The malic acid may be extracted from the juice of unripe fruits, particularly of apples, by faturating the juice with chalk, and adding a folution of acetite of lead ; the acetous acid combining with the alkali, and the lead with the malic acid, forming a Malate of lead, which is pre- cipitated. This precipitate being walhed, and diluted ful- phuric acid added to it, fulphate of lead is formed, and the malic acid left Befides various fruits, many of which yield both it and the citric acid, fugar alfo yields it, when treated with nitiic acid. Vauquelin has alfo difcovered the malate of lime in the fedum album, acre, et telephium, in many fpecies of craff'ula, 1-34 -in all the cotyledons he examined, in many of the msfemhy. .anthema, and in common parfley. He obferves, when the 1 juice of a plant furnifhes an abundant precipitate with an oxalate of ammoniac, and alfo a light flocky precipitate, with acetite of lead, which is eafily foluble in vinegar, it afluredly holds a malate of lime.-------Ann. de Chim. •C. 104-. With the alkalies it forms deliquefcent falts; with the earths it alfo forms malates, that of alumine being dif- ficultly foluble. The malate of iron does not cryftallize, but that of zinc forms in fine cryftals. It precipitates the nitrates of lead, of filver, or of gold, in the metallic ftate. It is readily deftroyed by fire, or converted into the carbonic ac'.d. The nitiic acid changes it into the oxalic acid. Vauquelin fays, perhaps, by being oxygenated by degrees, it at laft contributes, in fome plants, to form the oxalic acid. 3. The gallic acid, which is alfo yielded by many barks, roots, fruits, &c. may be thus obtained. One pound of powder of nut galls may be infuled in two pints and three-quarters of water, for four days, fhaking the mix- ture frequently, and then filtered and left in a veflel covered .merely with blotting paper. The liquid will then become covered with a thick pellicle of mouldirrefs, and a precipitate falls down in proportion as the infufion evaporates. Thefe precipitates being collected, and diflblved in boiling water, form a liquid of a brown yellow colour, which, on evapo- ration by agentleheat, depofits the acid in a precipitate like fine land and cryftals of a yellowifh grey,-it not being pof- fiblc to obtain it white. It may alfo be obtained by fublima- tion. It gives an acid aftringent tafte, effervefces with chalk, and reddens turnfole. Half an ounce of this fait is foluble in an ounce and a half of boiling water, or in twelve ounces of cold water. Boiling fpirits of wine diffolves its own weight of this acid ; but cold fpirits only one fourth. It is inflammable, it alfo melts and leaves a coal of dif- ficult incineration. By diflillption it gives out an acid phlegm, and a fublimate nearly of the fmell and tafte of acid of benzoin. Dejeux thinks its radical is fimply carbon, and that it a differs from carbonic acid only in the quantity of carbon, fl But Gren thinks that, as it is, like the acids jufl fpoken of, convertible into oxalic acid, by nitric acid, its bafis is com- j pofed of hydrogen and carbon. j X'55 Tt precipitates the feveral metals in different colours. Gold, of a brown colour ; filver, of a grey ; mercury, of an orange; copper, of a brown; lead, of a white; and iron, of a- ££»-£ colour. The bafis of ink is iron thus precipitated. Proufi con- Gders ink as a folution of gallate and tannate of iron in ful- phuric acid ;. and prefers ink made by a folution of iron itfelf in in fufion of galls. The juice of walnuts (green) prefent the fame appearances on digeftion with iron. It is only the red oxide of iron, (oxidated ad maximum) that forms the ink with the galls ; but whichever fulphate is em- ployed, when the ink is Jpread on paper it blackens, from the oxygen it abforbs. Sulphurated hydrogen gas parted through ink makes its colour difappear, but on being ufed, the oxy- gen it abforbs prefently blackens it; at firft the oxide of the fulphate is oxidated ad minimum, and then becomes oxida- ted ad maximum.----Ann. de Chim. C. 103. Boil four ounces of logwood near an hour in fix quarts, beer meafure, of water, fupplying the wafte dining boiling, and afterwards adding water to make up five quarts ; to this liquor drained whilft hot, add when cold 20 ounces cf galls coarfely bruifed, 4 ounces of fulphate-of iron calcined to whitenefs, half an ounce of acetite of copper firft moiftened and pounded into a pafte, 3 ounces of coarfe brown fugar, and 6 ounces of gum arabic or fenegal. This makes a good black ink, but for ordinary purpofes, half the quan- tity of the two latter ingredients may f'uffice.-—Deformeaux, Phil. Mag. Writing in common ink may be effaced by diluted oxy- muriatic acid, and may be again reftored by dipping the pa- per in a very weak folution of fulphur cf ammonia or of tha pruffiate of pot-afh, to which a few drops of the fulphuric acid, have been added. Old writings maybe revived by a fimilar employment of thefe fubftances. To prepare inks which will not be effaced by the oxy- muriatic acid, indigo and the oxide of manganefe may be added. Tannin, or that fubftance which acts as a tanning prin- ciple, combining with the gelatinous parts cf animals, and thereby preventing their decay,, is generally iound to ac- company the gallic acid in the bark, ligneous part, &c. of vegetables. , To obtain the tanning principle in the readieft manner, a faturated folution cf carbonate of pot-ash is.to be poured in a very ftrong infufionof galls, when the tannin is precipi- tated in whiiifh yellow flocks ; which muft be wafhed with a very fmall quantity of cold water. The quantity remaining in 136 folution may be precipitated by infpifTation. The whole precipitate being fpread thin, dries in a ftove and affumes a refinous form, of an acid bitter tafte, foluble in hot water and in alcohol, and by diflillation yields a faline liquor, in which the fmell of ammoniac is diftinguifhable. This fo- lution holds tannin, which volatilizes unchanged, and which blackens the red oxide oi iron, but does not become green with alkalies. The foregoing precipitate appears to be formed by the fait, which is added, having a greater affini- ty for the water than the tannin has; at the fame time, that the carbonate of alkali faturates the gallic acid, which has the property of holding the tannin in folution. The aque- ous folution of tannin lathers like foap water, and being poured into a folution of glue, it directly converts it into a magma, which pofleffes the elaftic properties of the gluten of wheat. As all faline fubftances will precipitate the tan- nin, and as the animal fluids contain falts; it is not to b« inferred from a precipitation on a mixture with infufion of tannin tha thefe contain glue. It is the preferving princi- ple of tanned leather. By its action on animal fubftances it renders them foft, fupple, and lalting, diminifhes their attraction for water, and prevents their becoming the food of infects.-----Prouft. Ann, de Chim. C. 103. As the gallic acid corrugates the furface, and does not feem to combine with the matter of fkin, Mr. Biggin thinks its prefence in tanning is not only ufeltfs but detrimental -----Phil. Trans. The green fulphate of iron is not altered by the tanning principle, any more than by the acid of galls. But the red fulphate is precipitated by the tanning principle, in a fome- what tarniflied blue depofition, different from that by the acid of galls. Bcfides, the gallate of iron is foluble in acids, but the tannate of iron is decompofed by thefe falts.-----Prouft. 4. The benzoic acid is obtained by boiling 4 parts of benzoic with 1 of lime, and 4 of water, ftirring them together over a gentle fire for half an hour, by which, the acid unit- ing with the lime, the benzoate of limk is formed. Af- ter fettling, the clear liquor is poured off, and the procefs twice repeated with frefh lime-water. The liquors fhould be then filtered, and muriatic acid added as long as any pre- cipitate, which is the acid of benzoin, falls. To have its cryftals, it muft be diffolved, filtered, and gently evapo- rated. It maybe a fo obtained by fublimation, in the form of flowers of Benjamin. 137 It reddens the infufion of violets, effervefces with the al- kaline carbonates, and unites with earths, alkalies, and metals, forming ben zo ate s. A fimilar acid is obtained from balfam of Tolu and fiorax. The effects produced on it by the nitric acid are not tho> roughly known. It differs, however, from the other vege- table acids, and retains an effential oil, which gives it fmell, volatility, combuftibility, and folubility, in alcohol. Diftilled with fulphuric acid, and the black oxide of man- ganefe, it is decompofed, and becomes acetic acid. 5. Acid of tartar is obtained from tartar, or the tartareous ACidUle, which is pot-afh fuperfaturated with tartareous acid, and is formed on the fides of calks during the infenfible fermentation of wine. It may be al- fo obtained from muft, or unfermented wine, and from fe- veral fruits. Expofed to heat it yields oil, phlegm, carbo- nic acid, and hydro-carbonate gas, and leaves in its afhes a confiderable quantity of vegetable alkali. Purified acidulous tartrite of potash, or cryf- tals, or cream of tartar, is obtained by folution of the above, and by fubfequent filtration and evaporation. It cryftallizes in tetrahedral prifms> cut off" flantwife, and requires for its folution 160 parts of cold, and a£ of hot water. The aciD of Tartar may be obtained, by diffolving two pounds of cryftals of tartar in water, and throwing in chalk by degrees, Until the liqu'd is faturated^ A precipi- tate forms which is a true tartrite of lime, taftelefs and crackling between the teeth. By adding 9 ounces of ful- phuric acid, and 5 ounces of water to this tartriie, and di- gefting them together for twelve hours, the tartarous acid is fet at liberty, and may be cleared from the fulphate of lime by means of cold water. This acid yields tabular and fpear-like cryftals, which become black when expofed to the fire, yielding hydro-carbonate, and carbonic acid gas, an acid phlegm and fome oil, and leaving a fpongy coal behind. Its radical therefore confifts of hydrogen and carbon, which^ with oxygen, form this acid. This acid is very fharp, but has no action on platina, gold, filver, or antimony, and fcarcely any fenfible action on copper, lead, and tin; but it diffolves their oxides. It afts on iron with a Confiderable degree of effervefcence. With the earths if alfo combines very freely. Boiled with the fulphuric acid, the tartarous is for the moft part converted into acetic acid.——Gren. By a neutralization of the acidulous tartrite by a farther addition of pot-afh, the tartrite of pot-ash, or as it 135 was improperly called, foluble tartar, a triple fait is form- ed. The addition of foda to the acidule forms the tar- trite of soda, formerly called fal rochelle, or fel dt feignette, which cryftallizes in tetrahedral, rhomboidal prifms. The tartrite of ammoniac forms cryftals of tetra- hedral prifms with obliquely truncated fummits.----Gren. The cryftals of tartar are rendered more foluble by the addition of borax. The tendency of the tartarous acid to unite with a certain portion of pot-afh, to form tartar, is fo great as to produce a feeining exception from the general laws of affinities. Even fuch acids, the acetic for inftance, as are not fo ftrong- ly attracted by pot-afh as is the tartarous, decompofe the neutral tartrite of pot-afh, and feparate from it, not the tartarous acid, but the acidulous tartrite, the confequence of the tartarous acid retaining this certain quantity of alka- li. A fimilar circumftance is obfervable alfo with the fol- lowing (the oxalic) acid, a fufficient quantity of alkali be- ing left to form the acidule.-----Gren. 6. The oxalic acid is obtained chiefly from the fait of forrel, of which we will therefore firft fpeak. Oxalic acidule, or fait of forrel, confifting of oxalic acid and oxalate of pot-afh, is obtained from the juice of the oxalis acetofella. It forms fmall white needle-like cryftals, of a penetrating auftere tafte, and as the acid unites with other bafes, without quitting its own, like the acidulous tartrite of pot-afh, it alfo forms triple falts with the alkalies, earths, and fome of the metals. The oxalic acid obtained from the oxalic acidule, by depriving it of the pot-afh it contains, has a penetrating four tafte, it effervefces in the air, is foluble in twice its weight of cold, and half its weight of hot water. It forms oxalates with the alkalies, making, With pot- eft}, the oxalic acidule, or the fait of forrel of the fhops. It combines more readily wth metallic oxides, than with. the metals themfelves. With arfenic it forms very fufible volatile cryftals ; with cobalt, a light rofe-coloured pulve- rulent fait ; with nickel, a greenifh yellow fait; with calx of bifmuth, a fait in powder; with calx of antimony, in cry- flalline grains ; with manganefe, a powder becoming black by heat; with zinc, a white pulverulent fait ; with tin, if the folution be flowly evaporated, it forms prifmatic cryftals; if quickly, a tranfparent mafs like horn ; with lead, it lorms white, with iron greenifh, and with copper light blue 139 eiyftals. An oxalated silver is obtained by adding7 this acid to the nitrate of filver in folution : it alfo diffolves the precipitate of platina, by foda ; but has fcarcely any action on the calx of gold. It combines with alumine, magnefia, and barytes. Its affinity with/;';»? is fuch that it takes it from every other fubftance, forming an almoft indecompofable oxalate of lime. It is therefore employed to difcover this earth in combination or folution. The oxalate of ammonia is pre- ferable for this purpofe. Brugnatelli fays that the oxalic acid cannot be depended on as a re-agent on lime, fince he difcovered that, in feveral inllances, the prefence of lime was afcertained by other known re-agents, when the oxalic failed. Ann. de Chim* No. 86, Vegetable acids obtained by the ufe of nitric acid. Sugar, mucilages, mild oils, flour, and even a ^reat number of animal fubftances afford, when heated with* the nitric acid, an acid perfectly fimilar to the acid laft de- fcribed. Thefe fubftances contain, therefore, the oxalic radical, to which oxygen only is wanted to be added, to convert it into oxalic acid ; this acid like other vegetable acids, being probably a compound of hydrogen, carbon, and oxygen. Berthollet obtained from wool more acid than half the weight of it. Since feveral vegetable acids, and in particular that of tartar, pafs to the ftate of oxalic by dif- tillation with weakened nitric acid, we may conclude thefe vegetable acids have the fame radical, and differ only in the proportion of oxygen. By concentrated nitric or fulphuric acid and ftronger heat, both the tartarous and the oxalic are converted into the ace- tic acid.----Gren. 7. Camphoric acid, which is obtained by means of the nitric acid, feems to differ in fome refpects from the oxalic. It yields cryftals refembling the muriate of ammo- niac, which are very fparingly foluble in water. With Pot-afh it forms cryftals in regular hexagons ; with foda,, irregular cryftals ; with ammoniac, it forms needle-formed cryftals.; with magnefia, a white pulverulent fait. It dif- folves copper, iron, bifmuth, zinc, arfenic, and cobalt; the folution of- iron yielding a yellowifh white, infolubie pow- der. With manganefe it forms cryftals whofe planes are parallel, and in fome refpectus refembling bafaltes. It burns without leaving any refidue, does not precipitate lime from lime water; nor does it produce any change in 140 the fulphuric folution of indigo. Its falts exhibit a bine flame with the blow-pipe. Bouillon la Grange. Doerffurd has proved that this pretended acid is the fame with the benzoic acid. Nor is this an educt obtained or feparated frOm the camphor by the procefs, but a product at that time generated.----Gren. Principles of Modern Cbi- miftry. 8. Suberic acid, obtained, as its name imports, from eork, is bitter, pungently acid, and deliquefcent, becoming brown by expofure to folar light. Its elective attraction! are fiift to baryt, then to pot afh, foda, lime, ammoniac, mag- nefia, and alumine. It differs from the gallic acid in its yellow precipitation ; from the malic in its folid form ; and from the acid of tartar, in not burning or fmoking on hot coals. It gives a green hue to a folution of the nitrate of copper, without occafioning any precipitate, and has a weaker attraction for lime than the oxalic acid. Unlike the camphoric, it turns the fulphuric folution of indigo green,. •Bouillon la Grange. To explain the action of sulphuric acid on dryttegf' table fubftances, Fourcroy obferves, that on putting aftraw* in this acid a black powder is precipitated, and the acid weakened without being decompofed. The acid, he- fup- pofes, decompofes the ftraw, by attracting fome of it's water of compofition, thus deftroying the mutual attraction of its component parts. A portion of the carbon is preci- pitated unchanged, and another of it is combined with thd hydrogen, and a part of the oxygen of the vegetable' fub- ftance, to form the acetous acid, which is found after the procefs to be combined with the fulphuric acid, while. the remaining hydrogen and oxygen form the water with which the mineral acid appears to be diluted.——Ann. de Chim. xxm. Acids obtained by the action of fire, or empy- reumatic acids. 9. Pyro-tartarous acid is yielded by dr? diflilla- tion, by the tartarous acidule. Its faline combinations are Called PYRO-TARTRITES. 10. Pyro-mucilaginous acid is obtained by dry diflillation from infipid, faccharine, gummy, or farinaceous mucilages. It renders the fkin of a red colour, and forms pyro-mucites with the earths and alkalies, with lead, copper, tin, and iron. The acid thus obtained Gren believes to be only a mixture of acetic and oxalic, and does not think it- defeives to be confidered as a peculiar acid. 141 n. Pyro-lignous acid is obtained by dry difffl- lation from wood, and particularly from beech, birch, and box. With earthy and alkaline bafes it forms pvrohg- nites. Gren fuppofes thefe acids to be produds of the operation> rot eduds which have actually exifted in the fubftance. From the experiments of Vauquelin and Fourcroy, it ap- pears that the three empyreumatic acids are merely the ace . tous acid impregnated with empyreumatic oil, of which it appears to be an actual diffolvent.——Ann. de Chim. 1800. iz. The acetous acid is the refult of what is termed the acetous fermentation, of which it will be neceffary firft to fpeak. Fermentation of vegetable substances. Fermentation takes place, accompanied by a decom- pofition, when the various parts of vegetables are diffufed in water, and the action of this fluid is favoured by the combined aid of air and heat. The firft agent of fermentation appears to be oxygen gas, which is afforded either by the atmofphere, or by the decom- pofition of the water; oxygen gas being abforbed, and calo- ric feparated during the procefs. When the faccharine principle predominates in the fubftances employed, the product is a fpirituous liquor, and the procefs is termed, the fpirituous fermentation ; but when mucilage is moft abundant, the liquor foon raanifells an acid, the procefs by which it is formed being termed the acetous fermentation; and if gluten be prevalent, ammo- niac will be difcovered in the product, and the procefs will be the putrefcent fermentation. No fubftances but thofe which confift fimply of carbon, hydrogen and oxygen are fufceptible of the vinous fermentation. It appears that ni- trogen and lime combined with the carbon, in gum, pre- vents the vinous, and confequently the acetous fermen- tation. Spirituous fermentation is employed for making wine, cider, beer, perry, Sec. Thus the muft or juice of grapes, at about 700 F. foon becomes turbid, and agitated through its whole mafs, feparating carbonic acid gas, and a frothy fubftance called yeaft. This procefs ceafing, the liquor becomes cleaV and bright, and has obtained a vinous odour an \ tafte, with certain intoxicating powers ; the lees of the wine fettling to the bottom. Even after this an im- perceptible fermentation goes on which occafions the ditter- ence between new and old wine.—During thefe feimenta- 142 tions tartar is depofited on the fides of the veffels. If the fermentation be impeded, whilft at its height, by the exclu- sion of air, as in bottling, the -,ne on the firft opportunity, Jets the impnfoned gas, formed after its feclufion frcm ttic air, efcape rapidly, as in the fparkling Champaigne wines, cider, perry, Sec. r * ' - Flour is. likewife difpoftd to fermentation, efpecially if the gram be hid malted, which is thus perfoimed : Barlev which is generally chofen for this purpofe, ,s fofiened by making ,n water, and then piled up until the grain has-eer- minatcd about 23ds of its length, the farther germination is then flopped by drying in a kiln, or airy lofts. When dried in the latter way it is called air dried malt,, and in the tormer kiln-malt. Beer is made from malt by infufine ground malt in boiling water in amafb-tub, itbeing then calied mafb, and the infufion drained off is called fiweet wort. To give it a pleafant flavour, it is then boiled witlj hops, then the decoction is fpeedily cooled to prevent the acefcent fermentation, and removed to the fermenting vat, where, by theaddition of a little recent yeaft,."fermentation is foon excited. Then, laltly, when fermentation has thus continued a proper time,, it is. preferved from the air in "Jj or bottles, and is then called cafked or bottled beer. When it derives a colour from the malt having been high dried in the kiln it is called brown beer, and when the malt has been but flightly heated, or dried in the air, it is then called pale beer. Thefe fermented liquors yield, by diflillation, an ardent and inflammable fpirir, poflefling an aromatic and refinous fmell, a penetrating and hot tafte, and an inebriating quality. Such is rhenish brandy, diftilled from wine lees; French brandy, from the hujks'and ftalks of grapes; rum, from the juice of the fugar-cane; melasses spi- rits, from the refufe of fugar ; and malt spirits, from grain. Alcohol is produced by a re-diftillation or redifi- cation. Even animal milk, from the fugar it contains, is capable of the vinous fermentation, and of affording a fpirit; fuch is the koumiss, made from mare's milk, by the Tartars. • Alcohol, or spirit of wine, appears to be formed by an intimate union of much hydrogen with carboiu Mr. Lavoifier obtained eighteen ounces of water by burning one pound of alcohol. Alcohol may be freed from its redundant water, not onlv by diftiilation, but by the addition of fixed alkali, which 143 attracts-the Water, in which it becomes diffolved, thealcohol fwimming at the top, anfl containing a fmall portion of the alkali. The mixture of a portion of water and of alcohol has been obferved to fill a lefs fpace, than would be filled by the Aim of their feveral volumes. It diffolves fugar, but in lefs quantity than water, and as it coagulates mucilaginous matters, it ferves to clear the faccharlne matter from mucilaginous particles. It diffolves the refins, effential oils, and foap, but does not diffolve fat oils, animal fat, fulphur, pruffian blue or phof- phorus. Ether, or naphtha, is formed by diftilling equal parts of fulph-ui iejfcid and alcohol, the oxygen of the acid combining with th^iydrogen and carbon of the alcohol. If the diftil- latiu^r oe continued beyond the production of the ether, a yejrowoil, called sweet oil of wine, is produced, which M heavier and lefs volatile than the ether. Ether is exceedingly light and volatile, and of a peculiar fmell; is fparingly foluble in water, and burns with a bright flame. Fourcroy and Vauquelin attribute the formation of ether to the attraction of the fulphuric acid for the water of the alcohol. Van Mons fays, that a muriatic ether may be compofed by one operation, if you diftil, at a boiling heat, a mixture of alcohol and oxy-muriate of pot-afh in the proportion of 1,00 to 0,25. By limply mixing the fulphuric and muriatic ethers, inftantaneous evaporation takes place, and the abforption of caloric is fo rapid as immediately to congeal quickfilver. Hoffman's anodyne liquor is a folution of ether in alcohol, and is made by uniting two ounces of fpirit of wine with two ounces of ether and twelve drops of fweet oil of wine. Meffrs. Bondt, Dieman, Van Trootfwyk, and Lawren- berg, have difcovered that by the diftiilation of ether, or of a mixture of fulphuric acid with alcohol or ether, or by caufing the vapours of alcohol and ether to pafs through a tube of clay ignited, or through the component parts (alu- mine and filex) of fuch a tube, a gas is obtained, which they have called the carbonated oily hydrogenous gas: which on being mixed with oxygenated muriatic acid gas, manifefts the extraordinary property of forming an oil. But if the diftiilation be made through a glafs tube, or if this gas be made to pafs through a glafs tube, the property of 144 forming oil is loft, carbon being depofited.—-—Ann. de Chim. xxi. Two parts of muriate of foda, one of manganefian oxide, three of alcohol, and one of fulphuric acid, being diftilled with a gentle heat, a dulcified oxy-muriatic acid firft rifes, and at laft a little oily fluid of a pleafant odour and aromatic tafte, and which finks in water, comes over. This has been called oil of fait; perhaps it refembles the oil juft fpukenef in its mode of production.----Gren. Acetous fermentation appears to'depend, as has been juft remarked, on the mucilaginous principle. Vegeta- t bles or their juices containing this principle, being expofed to the air, become heated, and the liquid parts turbid; a lively fmell is emitted, and much air is abforb|d. After fome time, a confiderable quantity of lees fettle^deaving above them a clear acid liquor. If wine be allowed to continue too long fermenting, Or if expofed to too great a heat, it runs into the acetous ferment tation and forms wine vinegar. Beer, in the fame manner,^ produces common vinegar, or alegar. The growing four of milk is a true acetous fermentation, and both the oxalic and tartareous acids, may, without addition, be changed to the acetic acid, by fermentation. Vinegar may be concentrated by diftiilation, or by freezing, when it forms the acetous acid, which united with pot-afh, forms the acetite of pot-ash, alfo called improperly, terra foliata tartari; with foda, the ace- tite of soda ; and with ammoniac, the ammoniacal acetite, generally known by the name of Mindererns'% fpirit. i Acetic acid, alfo called radical vinegar, has been 1 fuppofed to be "formed by introducing a ftill larger quantity of oxygen, than it in general contains, into the acetous j acid. To do this, the acetous acid is combined with fome of the metallic oxides, and expofed to diftiilation, when the * higher acid is obtained. Or half its weight of fulphuric j acid may be mixed with acetite of foda and diftilled. It is j moft probable that the difference arifes only from the pro- portion of water the acids contain. Acetic acid, as it is termed, is very acrid and volatile, emitting, when heated, an inflammable vapour, and form- ing with alkalies and earths, falts different from thofe formed by common vinegar, and which are diftinguifhed by the term acetates. It will alfo form ether with j alcohol. 145 The formation of vinegar appears to be the refult of the combination of oxygen with carbon and hydrogen, Four- croy and Vauquelin obferve that, the greater part of the pro- ducts of vegetable life, and among thofe of animal life, the animal jelly, cheefy matter, and uree, the peculiar matter of urine, are fufceptible of acetification. The converfion into the acetous acid appears to depend on four circumftances. lit. The decompofing action of fire by diftiilation, by which the conftituent parts of the fubftance are fo combined as to form the acetous acid, water and carbonic acid gas being alfo formed at the fame time, with charcoal, which is pecipitated. 2dly. The action of ftrong mineral acids, by which water and carbonic acid alfo are formed, and charcoal depofited. This acetification appears to be the laft ftep of vegetable acidification ; fince if employ- ed to the acetous acid, it deftroys its acid nature and reduces it to carbonic acid and water, as is the cafe with every vege- table decompofition pufhed to its maximum. 3dly. The acetous fermentation, in which there is neither precipitation of charcoal, nor difengagement of carbonic acid. In this procefs the oxygen of the atmofphere is abforbed, and the pre-exiftence of a vinous ftate is fuppofed. 4thly. A fpecies of fermentation not requiring the prefence of wine, and has fome connexion w th the putrid decompofition. It takes place in animal fluids, particularly in urine.——Ann. de Chim. Call. 104. Scheele has formed vinegar by decompofing the nitric acid on fugar and mucilage. In the making of bread, the vinous and acetous fermenta- tion take place ; the former foon yielding to the latter, the flour kneaded into dough with water, having acquired this (late, is called leaven, and if added to more dough it haftens its fermentation. But if baked before fournefs is dfcover- able good bread is formed. Yeaft is alfo ufed to promote the rifing of dough. Cit. Chautran has obtained an acid from the mildew of corn. This acid differs from phofphoric acid, forming an infolubie fait with lime and ammonia, and cryftallized fait with pot-afh. The mildew itfelf, he thinks, is of an animal nature.-----Soc. Philom. 1800. XIV. Alkalies exift in plants, combined with oils, acids, &c. and fometimes very (lightly engaged. They are generally obtained, by deftroying all the other princi- ples of the plant by fire. The alkali, in general, obta ned 14 G from vegetables, is pot-afh. Marine plants yield foda. Plants alfo are found to contain ammoniac. Such are onions, muftard-feed, tobacco, the fungi, Sec. Plants alfo yield neutral falts formed by the combination of the acids with the alkalies. Whilft confidering the alkalies thus difcovered in plants, we are however not to omit to reckon on the confiderable •effects attributable to the combinations which erifue, in confequence of combuftion. The atmofpheric air, during this procefs, will unite with fome of the vegetable prin- ciples, and produce certain refults : and perhaps the nitrogen may, by its union with certain principles, form alkalies, or at leaft augment or actuate thofe which exifted in .the plant. The alkali thus obta'ned is, in fact, a neutral fait, con- taining carbonic acid ; and which, as is the cafe with the boracic acid, in borax, is chemically, not merely mechani- •canically, fuper-faturated with its alkaline bafis.----CrelVt Journal, 1800. XV. The colouring principle is found in vege- tables in four ftates of combination :— i. with the extractive principle, as in logwood, co- chineal, &c. •2. ' i ' refinous principle, 3. . faecula, as archil, indigo, &c. 4.. , gummy principle. The art of dying, confifts in transferring the colour- ing principle of one body to another, fothat it fhall be dura- bly fixed. Colours are all formed in the folar light; the various tinges of colours refulting from the abforption of fome of the rays of Jight, and the reflection of others. By the art cf dying, a fubftance poflefling the property of reflecting particular coloured rays, is transferred to the furface of another body. The pigments or colouring matters employed in dying are, according to Dr. Bancroft, either fubflantive, fuch as are taken up by ftuffsnot previoufly prepared ; or adjedive, which are not abforbed by the fluff unlefs it has been mace- rated in fome fubftance called a mordant^ which either by imparting oxygen or otherways, alters its fubftance, and becomes a bond of union between the colouring matter and the Ituff; or acting on the colouring principle gives to it the .defir.ed tint, or, by coagulating it, renders it fixed, fince 1*47 being no longer foluble in water, it is not removable ly wafhing. When the colouring principle is held in a fubftance of the nature of extracts, water diffolves the whole of it as in log- wood, madder, &c. Into an infufion of this colouring fub- ftance the fluff to be dyed is therefore plunged, being firft, if neceffary, fteeped in its mordant. Some refinous colouring matters are only foluble in fpirit of wine, and are therefore only ufed in the fmaller articles, fuch as ribbons, &c. Other colouring matters are combined with fecula, which water alone does not diffolve, fuch are archil, indigo, Sec. The colouring matters of this clafs are, however, all foluble in alkali, or lime j thefe fubftances are therefore ufed to diffolve them in water, that tlfey may be precipitated upon fluffs.- This- may be done by the addition of an acid. Acids may be ufed inftead of alkalies, in fixing fome of thefe colours upon fluffs, thus may indiga be diffolved in the acid of vitriol, inftead of in lime. Some colouring principles are fixed by a refin-;- but which, by the afliftance of extradive matter, may be fufpended by water. Stuffs being boiled in this folution, the refinous part applies itfelf and adheres, fo as not to be liable to be again carried off by water. The chief fub- ftances of this kind are fumach, fanial, the huffs of wal- nuts, Sec. The colouring matter of fome vegetables are only extracted by oils, fuch is the alkanet root. The mordants are chiefly of an acid mature, fuch as the fulphate of alumine,, acidulous tartrite of pot-afh, folution of tin in nitro-muriatic and oxy-muriatic acid, gallic acid, fulphate of copper,, of iron, and of zinc, acetite of copper, arfenic, Sec. Blue, red, and yellow, are the fundamental colours, by combining thefe, on the fluffs, rarely in the bath, the various hues are obtained. The fluff, preparatory to the application of the colouring matter, muft be cleared of all glutinous matter which belongs to it in its natural ftate; it muft alfo be'bleached and impregnated, when that is neceffary, with the mor- dant. The removal of the glutinous matter from the fibres of the fluff, which would prevent the reception of the colour, is accomplifhed by wafhing in a folution of foap, of alkali, and particularly of foda. .The operation of bleaching, or whitening, which will much contribute to the brilliancy of the fubfequent colour, .depends on the action of oxygen, which combines with tlie colouring principle which ftains 148 the cloth, and deftroys it. The moft common mode is that of boiling the pieces in an alkaline lixivium, and expofing them afterwards to the air, to render the whitenefs more per- fect' But the oxygenated muriatic acid produces the effect with fo much facility, that all former proceffes muft yield to it. J The oxy-muriate of pot-afh is alfo employed for this pur- pofe. Mr. Higgins recommends alternate immerfions in a folution of this fait, and in a folution of the fulphuret of lime thus made. Sulphur 4 pounds, flaked lime 24 pounds, and water 16 gallons boiled half an hour in an iron veffel, the liquor itrainedoff and 16 gallons more of water poured on the dregs and alfo drained off; the two folutions being mixed together and poured into 33 gallons more water, makes a liquor of a proper ftandard in which cloth may be deeped in the procefs of bleaching, the fulphuret ferving as a fubfti- tute for pot-afh for condenfing the oxy-muriatic gas____ Effay on Bleaching, fife. Wm. Higgins. The piece being prepared fo far by thefe proceffes, it is then impregnated with the mordant or principle which is to ^C1Vri 1 COlrUf' and rendeiit incapable of extraaion. I he fulphate of alumine and the muriate of tin are the two falts which are moft efficacious for thefe purpofes. The fluff thus impiegnated, is then paffed, through the colour- ing liquid, and by the decompofition or change of princi- ples between the mordant and the principle which holds the colour, in folution, the colour is precipitated on the bafe of the mordant, and adheres to ir. Some vegetable fubftances are likewife difpofed to take fome colouis by being animalifed. In this way, cow's dung and bullock's blood are ufed in dying cotton. Turiifol has been difcovered to be made by finely pow- dered lichen, archil, or even the greater mofs of the oaks, firft mixed with an alkali, and kept moift with human urine ; it becoming red and then blue, when it is mixed with one-third of pot-afh, by remaining with which it acquires a dark blue colour. It is then made into cakes, by a mix- ture with chalk, to increafe the profit_____Journal dt Commerce. The juice of aloes produces a lively violet, highly proper for works in miniature, and which may ferve either cold or warm, for dying filk, from thelighteft to the darkeft fhade. ■'■■ —Fabroni. Ann. de Chim. xxv. Indigo is a tascula obtained from the indi>o plant by fteeping it in water and allowing its fermentation, the co- 149 loured faecula falling in a blue flocculent fediment. Woad affords a fimilar faecula. The leaves are bruifed and formed into roundifh lumps, in which form they are fold by the name of woad. The leaves in this ftate undergo a flight fermentation, by which the colouring matter is in a great meafure fet free. In indigo, befides carbon and hydrogen, with fome nitro- gen and oxygen, there is,, according to Berthollet, i-3otft part of iron. Arnatto is prepared from the pulp of the feed capfules of a tree growing in Guiana. Sap colours are either infpiffated juices of plants, or extracts from.them. Lake colours are formed by precipitating alumine with the colouring matter, by adding fixed alkalies to a decoction of the plant, or its parts in alum and water- Brugnatelli obtained, by diftilling the nitric acid from indigo, a peculiar refin, of a deep yellow colour, and of half the quantity of indigo employed.----Ann. de Chim. LXXXVII. Guyton fuppofes the red colour of fruits to be owing to the re-action of their own acid on the colouring matter : and that tin, in reftoring the colour of violets, attracts from it the acid which had turned it red : lead, bifmuth, zinc, antimony, and particularly iron, doing the fame. The metallic oxides are not equally powerful ; but the oxide of tungften, he thinks, is fuperior to all others, in forming cakes for painters.----La Decade Philof. 179,8. XVI. Pollen, or the fecundating powder of the ftamina of vegetables, is generally of a refinous nature, foluble in alkalies and alcohol. Like refin it is inflammable, the aura round certain vegetables, may, it is-faid, at the time of fe- cundation, be fet on fire. XVII. Wax of bees is merely the pollen very little altered. There appears to exift in the very texture of fome parts of various vegetables, a matter analogous to wax. It appears that wax and the pollen have for their bafis, a fat oil, which paffes to the ftate of refin by its combina- tion with oxygen. If the nitric or muriatic acid be digefted on fixed oil for feveral months, it paffes to a ftate refem- bling wax. Wax, by repeated diftillations, affords an oil poffeffing all the properties of volatile oils. It is reduced into water and carbonic acid by combuftion. N * 150 Alkalies diffolve wax, and render it foluble in water. It is this faponaceous folution which forms the punic wax, which may be ufed as the bafis of feveral colours, and may be made into an excellent pafte for wafhing the hands. It is likewife ufed with a brufh, as a varnifh, on feveral bodies .- but it would be highly advantageous if it could be deprived of its folvent, which conftantly acts, and is the caufe why it cannot be applied to feveral ufes, in which otherwife it might be found advantageous. Ammoniac likewife diffolves it ; and as this folvent is evaporable, it ought to be preferred when it is propofed to ufethe wax as a varnifh. Chaptal. XVIII. Honey, or the nectar of flowers, is contained chiefly in the piitil or female organs. It appears to be a fo- lution of fugar in the mucilage. XIX. The ligneous part of the vegetable, forms the vegetable fibre ; and not only conftitutes the bafis of the vegetable, but alfo the hufk of feeds, lanuginous coverings, &c. Its character is infolubility in water, and almoft every .other menftruum ; even the concurrence of air and water alters it veuy difficultly, and it fo abfolutely refifts every kind of fermentation, as to be almoft indeftructible, but by \ infects. It contains the greater! quantity of carbon of any vegetable fubftance. XX. Aroma, theodorant principle in vegetables, which from its finenefs, invifibility, &c. has been faid to be of the nature of gas, perhaps fhould only be confidered as the odour of the volatile oil. XXI. Charcoal is an oxide of carbon, obtained from wood by the procefs termed charring, which is burning it, whiift the air is excluded as far as poftible, and yet to allow the combuftion to proceed. It is a folid, black, friable and infufible fubftance, ftill exhibiting the fibrous ftructure of the vegetable from which it has been produced. Its habitudes with other fubftances have been defcribed when fpeaking of carbon, and its combinations. Charcoal poffeffes the property of clarifying various turbid fluids, which, according to Mr. Lowitz, it appears to do by chemically combining with, and thereby feparating the difcolouring particles.——-Crell's Journal, 1800. Befides thofe already mentioned, various other principles have been found in the vegetable kingdom. Sulphur, in fubftance, is fiiid to be found in the dried fcum which rifes from the herb patience, whilft boiling in water. Iron, manganefe, and even gold, have been found in the afhes of 151 plants. Lime, alumine, magnefia, and filica, are alfo found in plants. Flint has been found within the joints of the bamboo. Bonnet cane and all cane of this kind, when brifkly rub- bed together, produce fparks of white light; and when vio- lently ftruck together, fparks, nearly as vivid as thofe from a gun-lock, are perceived, and a ftrong fmell at the fame time produced. Similar effects follow when the cane is fharply ftruck by fteel or any filiceous ftone. Thefe pheno- mena appear to proceed from the epidermis of the cane con- taining filex ; 22 grains of epidermis yielding about 9 grains of lilex. From 240 grains of the internal part of the cane, about 2 grains, apparently filex, were obtained. Other canes yielded much lefs filex ; but it was found in the Englifh reeds and graffes, in wheat, oats, barley, &c. Poflefling alfo carbonate of pot-afh with the filex, they yield glafs by the blow-pipe, a ftraw being thus converted into a fine pellucid globule of glafs.——Mr. H. Davy. Nicbolfon's Journal, May, 1799. The epidermis of the equifetum hyemale, or Dutch rufh, appears to be almoft wholly compofed of filex. Mr. Not- cutt obtained a globule of glafs from it by the blow-pipe.— Phil. Journal. Vegetables being expofed to the joint action of heat and air, the oxygen combines with the inflammable principles of the plant, and combuftion takes place with the production of fmoke, and the difengagement of heat and light. The fmoke is a mixture of water, oil, volatile falts, and all the gafeous products which refult from the combination of calo- ric and hydrogen with oxygen and the feveral principles of the vegetable, and hence carbonic acid and carbonated hy- drogen gafes, are alfo formed, and the empyreumatic acids. With the fmoke arifes foot, partly compofed of the carbon of fubftances imperfectly burned, having efcaped the action of the oxygen. Hence the foot may be again burned; and hence it is, that where, as in the lamps of Argand, and in violent furnaces, where the combuftion is more perfect, there is no perceptible fmoke. Soot, by analyfis, yields an oil, a refin foluble in alcohol, an acid formed by the decom- pofition of mucilage, alfo volatile falts, fuch as carbonate of ammoniac, and other neutral falts. The fixed principles remaining after the combuftion, form the afhes, containing falts, earths, and metals already treated of. By this procefs are obtained the fixed alkalies already fpoken of. Sul- phate of pot-afh is alfo fometimes found in thefe afhes. The fulphuric acid, here, in the opinion of Gren, is deri- 152 ved from the fulphur, which he confiders as one of the con- ftituent parts of wood, combining with oxygen, during combuftion. Distillation occafions a feparation of the principles of vegetables; all vegetables yielding nearly the fame, viz*. an oil, an acid water, a concrete fait, carbonic acid, and carbonated hydrogen gafes, and charcoal. The putrid fermentation takes place when vege- tables are heaped together, and f'oftened with the humidity with which they are impregnated, and by their own effufed juices. Their colours change, the mafs becomes of a dark brown, fwells, and becomes heated, and.as it is reduced to a magma, a gas is difengaged, which is a mixture of nitro* gen, hydrogen, and carbonic acid; ammoniacal gas is alfo. emitted. The whole is at laft refolved into a brown mafs, which for the moft part forms vegetable mould, being a mixture of all the primitive earths, and of the metals which' are found in vegetables as well as the oil, falts, &c. This refidue of vegetable decompofition may be confidered as the great agent and mean* by which nature repairs the con- tinual loffes the mineral kingdom undergoes, diamonds, quartz, cryftals, fpars, bog-ores, &c. being formed in this matrix. If this decompofition is accomplifhed in a clofe place, a foul mufty fmell is perceived from the feparation of the hydrogen. When, as in marines, a portion of animal matter is at the fame time decompofed, ignes fatui, and fuch luminous ap- pearances may accompany the dilengagement of hydrogen, and of phofphorus. Peat, or quick moss, appears to be vegetable matter deprived of its hydrogen ; during the procefs a black carbo- naceous matter, called peat earth, feparates, and this com- bining with oxygen, an acid is generated refembling the fu- beric acid. The peat in this ftate appears to be what Lord Dundonald calls oxygenated peat.——Jamefon's Minerals gy of the Shetland lftes. Agriculture cannot but be improved by an atten- tion to the daily difcoveries in chemiftry, thefe have taught us the food of plants, and the art of correcting the vices of a foil fo as to render it moft fit for vegetation. The fubftan- ces by which this is accomplifhed, are termed MANURES, and which are, of courfe, varied, according to the nature oi the foil on which they are employed. 153 For clayey foils the beft manure is marl, that which is moft calcareous is, with limeftone-gravel moft ufeful. Marl and dung is ftill more advantageous. Where thefe cannot be had, coarfe fand, lime, coals, afhes, chips of wood, burned clay, brick duft, gravel, or even pebbles are ufeful, for all thefe improve the texture, and fome of them fupply carbon. For chalky foils the beft manure is clayey or fandy loam, they wanting the argillaceous and fandy ingredients. For fandy foils the beft manure is calcareous marl, and next to this clayey marl, and then clay mixed with lime, or calca- reous or clayey loams. For gravelly loams, marls, whether argillaceous or cal- careous, are proper ; and if the gravel be calcareous, clay may be employed. For ferruginous loam or till, and vi- triolic foils, the calcareous ingredient is required to neu- tralife the acid. Boggy foils generally are helped with limeftone gravel, or lime mixed with coarfe fand or gravel, efpecially when of a clayey nature; but if more fandy, lime or calcareous marl will anfwer well ; in general they fhould firft be burn- ed, to liberate the carbonaceous principle. Heathy foils fhould, for the fame reafon, be burned, and limeftone gravel fhould be added when the foil is clayey, and lime when it is gravelly. By paring and burning the old fickly roots are defray- ed and coal is formed, by which the carbonaceous prin- ciple is reftored, which has been exhaufted by too many crops. Gypfum from its accelerating putrefaction is a moft ex- cellent manure, efpecially for clayey lands, and fuch as are dry and naturally fuit clover. It fhould be ftrewed on the furface in February, when it converts the old grafs into coal, and nourifhes the young growth. Befides the manures already mentioned, charcoal itfelf, and foap-boiler's vuafle have been fuccefsfully ufed. Lime has been found to be very ferviceable as a manure, but Mr. Tennant difcovered that lime procured from magne- fian limeftone was injurious to vegetation. The fertilizing powers of dung proceed from its refolu- tion into foil or animal earth, and from its yielding car- bon and hydrogen. Dr. Ingenhouz recommends as ma- nures thofe fubftances yielding moft carbon, which taking up by the oxygen and caloric of the atmofphere would form carbonic acid gas, the food of plants. Inftead of fal- lowing he therefore recommends impregnating the earth 154 with fulphuric acid, as this, with the calcareous earth,, would form gypfum, and with the magnefia, Epfom falt^ from both which would carbonic acid gas be developed. The oxygenated muriatic acid, mixed in the proportion of half a cubic inch of acid and three cubic inches of water, made into a pafte with the-black oxide of manganefe, and feeds, produced the germination of feeds, which no efforts before could caufe to vegetate. The application of oxygen, in a mode fomewhat fimilar to the roots of plants, appears alfo to promote vegetation.----Humboldt. Journal de Phy- fique, 1798. Von Humboldt, who, we obferved,- when fpeaking of the earths in general, attributes to them the power of abforbing oxygen from the air, efpecially when aided by. heat and moifture, obferves that the fame property is poffeffed by every fort of clays, and fresh mould. Sauffure, junior, having made numerous experiment!), denies that pure earth, either filica, li.Tie, or alumine thus abforbs oxygen. In this he is confirmed by the experiments of Berthollet, and others. He afferts, however, that it is abforbed by mould formed of decompofed and decompofing organic fubftances.——Ann. de Chim. 1800. From this property, which the mould poffeffes, of abforbing oxygen, refults much of the advantage proceed- ing from tillage, fince by frequently changing the fur- face of the earth, the procefs muft neceffarily be accelerated. The tilled earth thus abforbing oxygen from the air, leaves the air at the furface in poffeflion of more than its common proportion of nitrogen.—Hence, on the Alps the atmofpheric air contains more oxygen than that of the warmer plains, the fnow preventing: the contaft of the air widi the earth, and of courfe this abforption of •xygen. OF ANIMAL SUBSTANCES. THE conftituent parts of* animal bod'es confiftof but a fmall number of radical principles; the'r various natures chiefly refulting from the different proportion in which thefe are combined. Thefe radicals appear to be nitrogen, carbon, hydrogen, phofphorus, oxygen, and lime. 155 •i. The Blood is that red fluid which circulates in the animal body, by means of the arteries and veins j and fup- ports life, by fupplying all the organs with the peculiar juices they demand. It varies in the fame individual, not only with regard to the ftate of health, but as to the part it occupies. The blood, whilft circulating through the veins, differs in intenfity of colour and degree of confiftence, from that which is pafling through the arteries. It putrifies by a gentle heat, and when llowly dried, effervefces with acids j if expofed to the air, it extracts humidity, and at the end of feveral months, yields a faline efflorefcence afcertained by Rouelle to be foda. The blood, when at reft, coagulates^ and then feparates into a yellow liquid, called serum, and a clot or coagu- lum. It may alfo be coagulated by alcohol and the acids, but alkalies render it more fluid. The serum has a greenifh yellow colour, is of a flight- ly faline tafte, turns fyrup of violets green, and hardens in a moderate heat, which is the character of lymph : it eafily putrifies, and then affords much carbonate of ammoniac. Diftilled on a water bath, it yields an infipid phkgm, neither acid nor alkaline, but very readily putrifying ; the refidue being tranfparent like horn, and no longer foluble in water, but yielding, by farther diftiilation, an alkaline phlegm, carbonate of ammoniac, and afetid blackifti oil, more or lefs thick : the remaining coal is very voluminous and diffi- cult to incinerate. The afhes afford muriate and carbonate of foda, and phofphate of lime. Being poured into boiling water, it directly coagulates, a part communicates a milky colour to the water, and poffeffes, according to Bucquet, all the properties of milk. The coagulable lymph, befides being the principle conftituent of the ferum of the blood, forms the cheefe in milk, and makes up the greateft part of the white of eggs* It coagulates at about 1500 Farenh. It has but little tafte, is diffolved by alkalies, is infolubie in water, oils, or ardent fpirits ; the latter as well as acids, and metallic folutions promoting its coagulation. When confiderably diluted with water it no longer coagulates with heat. It gives oxa- lic acid when treated with the nitric acid, and appears to contain carbon, hydrogen, nitrogen, oxygen, phofphorus, and lime. Gren. The coagulum of the blood, likewife contains much lymph, which may be carried off by wafhing. The colour- ing part, which contains much iron, may be carried off by the fame procefs. When the coagulum has been thus wafh- 156 ed, a white fibrous fubftance is left called fibrin, or the j fibrous part of the blood. It is void of fmell, and being dif- | tilled in a water bath it yields an infipid phlegm, eafily fuf- ceptible of putrefaction. The refiduum foon becomes dry, by a gentle heat; and if expofed to a confiderable heat, it fhrinks up like parchment; if diftilled, it affords the fame j refults as the coagulable lymph, but the coal is lefs volumi- 1 rousand lighter than that of lymph. The alkalies diffolve it, if aided by a boiling heat, and the acids combine with < "' . . ! The blood contains much iron. The colouring matter of ; the blood being burned, and the coal lixiviated, an oxide of iron is left, of a fine red colour, faid to be obedient to the magnet. ' The colour of the blood appears certainly to depend on the iron it contains ; but on confidering the changes which • take place during refpiration, and the different colour of ar- terial and venal blood, it feems that the colour is produced by the oxidation of the iron, during the paffage of the blood through the lungs—The blood which has juft circulated through every part of the animal, and has been brought -i back by the veins to the heart, is propelled into the lungs of •' a dark red colour, and impregnated with hydrogen and car- • bon. By infpiration the lungs are diftended with air, th« i oxygen of which combines with the carbon, forming carbo- nic acid ; and with the hydrogen, forming water; another part of the oxygen unites with the blood which returns from the lungs, and paffes into the arteries of a bright red. Gren, in a letter to Van Mons, fays, that the oxygen does not unite with the arterial blood, and that all the water in refpired air is newly formed, and not feparated from the blood. The oxygen is abforbed and forms water and car- bonic acid, and no part is left to unite with the blood ; the change in the venous blood depending therefore on the feparation of carbon and hydrogen.-------Ann. de Chim. ' XXIII. The whole of the blood, which by an3tomifts is divided into ferum, red globules, and coagulating lymph, is found, when chemically examined, to confift of albumen, gelatin, and fibre. The ferum which remains liquid after the coa- '\ gulation of the blood, is compofed of albumen, gelatin, fome faline matter and much water. The clot of ciaflamen- \ turn alfo affords, by repeated wafhing, a large portion of al- ; bumen and gelatin : after which a fubftance remains, in ap- | pearance, very analogous to animal fibre, excepting that it is in a more attenuated ftate. This fubftance (fibrin) may \ 157" be regarded as that part of the blood which has undergone the moft complete animalization ; and from which the muf- cular fibre and other organs of the body are formed.---- Mr. Hatchett. Phil. Trans. 1800. II. The gastric juice is fecreted in the ftomach of animals, and produces the digeftion of their food, which may be confidered almoft as a chemical procefs. The gaftric juice varies in different animals, according to the na- ture of their aliments: this difference extending to its chemical properties, and hence a variety in the analy- fis of the gaftric juice of different animals. It however, in general, yields water, animal gelatin, and phof- phates. III. The pancreatic juice is next added to the in- gefta, this liquid appears to be refolvable into the fame prin- ciples as thofe of the gaftric juice. IV. Milk is fecreted in thebreafts of the females of cer- tain animals, therefore called lactiferous animals ; but the following obfervations will chiefly refer to that of cows. It is the leaft animalized of all the fecreted fluids, partaking of the nature of the chyle, and even of the qualities of the aliments. When expofed to the air, cream rifes on its fur- face, the remaining fkimmed milk becoming four, in a longer or fhortertime, according to the temperature of the atmof- phere, in fummer acquiring its greateft acidity in three or four days, and feparating into a coagulum or curd, and a ferum or whey. Milk appears to contain a fat oil, and a particular glu- ten, formed into a kind of animal emulfion, by means of a faccharine fubftance. Milk is very remarkable for the phofphate of lime it con- tains, and which feems to be deftined to favour the firft pe- riod of oflification.——Foam-qy. Tabl. Synop. 1800. Lactic acid, or the acid of milk, is thus obtained. Sour milk being evaporated to one eighth, the cheefy mat- ter feparated by the filter, and lime-water poured on the refidue, an earth is precipitated, and the lime combines with the acid of the milk. The lime may then be difplaced, by adding the oxalic acid, which forms with it an infolubie oxalate and is precipitated, the acid of milk remaining dif- engaged. The fluid is then evaporated to the confiftence of honey, and upon this very pure alcohol is poured, which takes up the acid, all the other principles remaining undif- folved. The mafs being now filtered, the lactic acid may be feparated from its folvent by diftiilation. 153 The lactic acid forms deliquefcent lactates with the alkalies, baryt, lime, alumine, magnefia, Sec. It diflolves iron and zinc, and produces hydrogen gas. With copper it affumes firft a blue colour, then a green, and afterwards an obfcurebrown. It alfo diffolves lead, the folution depofit- ing a white fediment, confidered by Scheele .as a fulphate of lead, and as evincing the prefence of a fmall portion of ful- phuric in this acid. Sugar of milk is obtained from whey, or milk, depri- red of its cream and of its curd, and evaporated to the con- fidence of honey. This is formed into cakes, which are dri- ed in the fun, then diffolved, clarified, and fet to cryftal- lize ; it then yielding white cryftals, in tetrahedral prifms, with tetrahedral fummits. It has a flight earthy faccharine tafte, is foluble in three or four pints of hot water, and ex- hibits the fame appearances as fugar, either by diftiilation, or on tire fire. By diftilling the nitrous acid from twelve ounces of fugar of milk, Scheele obtained five drams of oxalic acid in long cryftals, and feven drams and a half of the acid of sugar of milk, in a white powder. The saccho-lactic acid is combuftible, and does not leave any afhes behind ; it is fourifti to the tafte, and reddens litmus. It yields, by deftructive diftiilation, a brown acid fait, fmelling like the flowers of Benjamin, or acid of amber. It is eafily foluble in fpirit, but not in wa- ter, and burns in the fire with a flame. It forms saccho- lactates with the alkalies and earths; thofe with the earths being infolubie, and that with ammoniac having a fourifh tafte. On the metals it does not act, but with their ealces it forms falts ot very difficult folubility. The ferum of milk may, by feveral proceffes, be made to pafs into the vinous fermentations. Six fpoonsful of alco- hol, with three pints of milk, expofed in clofed veffels for a month, giving vent occafionally to the gas, will be con- verted into good acetous acid. A fpirituous liquor is alfa made from mares milk. Milk is turned, or its various conftituent part.s are feparated fpontaneoufly, or by the ad- dition of rennet, and feveral other fubftances, fuch as neu- tral falts, acids, and even certain vegetables. The folid mafs thus feparated from the whey, contains two fubftances, cheefe and butter. Milk may be curdled by pafling through it the electric fluid, and then reftored to its fluid ftate by fixed alkali.----■ Bouillon le Grange's Manual, 1800. Cheese is formed by the curd undergoing a commence- ment of the putrid fermentation, by which it acquires con- 159 fiftency, tafte, and colour; and is then preffed and dried for ufe. No fubftance has a ftronger refemblance to cheefe than boiled white of egg, both being foluble in diluted acid, in cauftic alkali, and in lime water. The earth of cheefe, according to Scheele is a phofphate of lime. Ammoniac dif- folves cheefe more effectually than fixed alkalies, andnitric «nVdifengages nitrogen from it. Butter is procured from the cream which floats on the top of milk, by agitation, the remaining milk being termed butter-milk. Butter, unlefs falted, foon changes, be- coming rancid like oils ; the acid, thus developed, maybe wafhed off by water, or by the fpirit of wine. With fixed alkali, butter forms a foap. By diftiilation it yields water, a coloured concrete oil, and a ftrong pungent acid, the febacic acid. At Conftantinople the butter is obtained from the Crimea and the Cuban, they do not fell it, but melt it over a flow fire, and fcum off what rifes ; it will then preferve fweet a long time, if it was irefh when melted.-----Eaton's Survey of the Turkifh Empire. V. Fat is a condenfedin flammable animal juice, con- tained in its proper membrane. Its colour is ufually white, but fometimes yellow ; its tafte infipid, and its confiftence varying in different animals. It is obtained in a ftate of purity, by boiling in water, after being finely fhred; it being thus feparated from the membranes, fibres, Sec. It differs with the individual and the part of the body which produces it, thus we have tallow, mixed with offal parts; lard, from the hog; and train oil and fpermaceti from fifh. Fat much refembles oils ; like them it is not mifcible with wa- ter, is liable to rancidity, forms f.,ap with alkalies, and burns by the contact of an ignited fubftance. Beef-fuet diftilled on the water bath, affords oil and phlegm ; the phlegm is reddifh, has an acid tafte, effervefces with alkalies, and turns the fyrup of violets brown. Mar- row yields the fame produ&s, and a fubftance of the con- fiftence of butter. Sebacic acid, or acid of fat, thus obtained-, has been concentrated by various proceffes by Mr. Crell. Alka- lies, it is known, form a foap with animal fat; by heating this foap with a folution of alum, he feparated the oil and obtained the sebate of pot-ash, by evaporation. The fulphuric acid, afterwards diftilled from this fait, decompo- fed it, and the febacic acid was feparated. This.acid exifts ready formed in the fat, fince earths and alkalies difengage it, 160 Mr. Crell alfo obtained it by diftiilation from the butter of cocoa, and from fpermaceti. It feems to approach to the nature of the muriatic acid, in fome refpects, but not in others. Mr. Crell thinks its place fhould be between the mineral and vegetable acids. It lorms a cryftallizable fait with the oxide of gold, as it doe* likewife with that of platina. It unites with mercury and with filver, yielding the latter to the muriatic acid, but not the former; it takes both from the fulphuric. It alfo takes lead from the nitric and acetous acids, and tin from the ni- tro-muriatic. It attacks neither bismuth, cobalt, nor nickel,. nor decompofes the fulphates of copper, of iron, or of zinc, nor the nitrates of arfenic, manganefe, zinc, Sec. but redu- ces the oxide of arfenic. It unites with the carbonates of lime and alkali, with effervefcence, and forms falts very fimilar to the acetites cf the fame bafis. Crell formed with it a sebacic ether. The febacic acid treated with the nitric acid, may be con- verted into the oxalic, and acetic acid. From the foregoing analyfis, it appears that fat is a kind of oil or butter, rendered concrete by an acid, being, in fact, an acid foap. By ftill nicer analyfes, it has been efti- mated, that fix parts of fat confifts. of nearly five of carbon, and one of hydrogen, with fome febacic acid : and not yield- ing fo much oxygen and nitrogen as the flefny parts. Dr. Gren remarks, that though efteemed as a peculiar acid; yet after being purified and concentrated, it mani- fefts the fame properties as the acetic acid. Dr. Beddoes appears to think that fat is produced in the animal fyftem, in proportion to die diminution of oxy- gen. Oxygenated lard is formed by melting one part of nitric acid with fixteen parts of axungia, ftirring it with a glafs rod, and leaving it over the fire till it throws up bubbles. The nitric acid is decompofed, the nitrogen is difengaged, and the oxygen combines with the fat, without giving it acidity. -i Alyon. Spermaceti is a concrete oil, extracted from a fpecies of the whale, the cacbolot. It burns with a very white flame, and rifes totally if diftilled on a naked fire, affuming a reddifh tinge, and lofing its natural confiftence by repeated diftillations-. The fulphuric, acid diflolves it. The nitric and muriatic have no action on it. Alcohol diffolves it by the afliftance of heat, but lets it fall as it cools. It is alfo diffolved by eihtr* and by the fixed and volatile tilt. 161 VI. The bile is a fluid fecreted by the liver, depofited in the gall-bladder, and thence conveyed into the duodenum. It is glutinous, of the fluidity of oil; of a very bitter tafte, a green colour, inclining to yellow; and froths by agita- tion like a folution of foap. Diftilled on a water bath, it yields a phlegm which is neither acid nor alkaline, but foon putrifies; this phlegm, and the bile itfelf, fometimes, it is faid, emits a fmell like that of mufk. The refidue of this diftiilation is a dry extract, which attracts the humidity of the atmofphere, and is tena- cious, pitchy, and foluble in water. By more violent heat it yields ammonia, an empyreumatic animal oil, con- crete alkali, and hydrogen.—The coal is not difficult of in- cineration, and contains iron, carbonate of foda, and phof- phate of lime. Bile is decompofed by acids, by which a coagulum is feparated, which is foluble in excefs of acid, and which forms, with the muriatic acid, a red folution; an oily fubftance, analogous to refin, alio rifes, and falts are formed which have foda for their bafis. Bile is foluble in alcohol, by which the albuminous principle, which renders bile coagulable, and haftens its putrefaction, is alfo fepara- ted. The bile appears therefore to be a combination of foda with a matter of the nature of refins, and a lymphatic fub- ftance, which renders it fufceptible of prutrefaction and co- agulation. It unites with oils, and cleans fluffs in the fame manner as foap ; but does not appear to mix with oily fub- ftances in the fame manner as foap. When the bile becomes thick in the gall-bladder, it forms the concretions called biliary calculi:; concreted, it is fup pofed, by the abforption of oxygen. Thefe are foluble in general, in ardent fpirit; and when the folution is left to itfelf for a certain time, brilliant and light particles are feen in it,,which appear to have an analogy with the fait of ben- zoin, and with thofe which are found in the human calculi. There appear to be two forts of biliary calculi, the one opake, confifting of the condenfed bile, with a fubftance fimi- lar to wax or fpermaceti, and formed in concentric ftrata; the other compofed of cryftalline plates, fimilar to mica or talc, formed by the cryftals juft defcribed. Vfl. The soft and white parts of animals. The tendons, cartilages, ligaments, and fkin of animals, contain a mucous fubftance, very foluble in water, but not in alco- hol ; known by the name of GELATIN or animal jelly. It is obtained merely by boiling any of the foregoing fubftan- ces in water : it has in general no fmell, and is infipid to the tafte. By diftiilation this jelly yields an infipid and in- O z 162 odorous phlegm, which eafily putrifies; by a ftronger heat it fwells, becomes black, and emits a ftrong odour, with white acrid fumes •• an alkaline phlegm, an empyreumatic oil, and a little carbonate of ammoniac paffes over; and a fpongy coal remains, difficult of incineration, and which contains muriate of foda and phofphate of lime. As it putrifies, a large quantity of nitrogen, hydrogen, and carbonic acid gas, is emitted. It is diffolved by acids, but more readily by alkalies i and with nitric acid, nitrogen gas is difengaged. It feems to differ from the vegetable jelly, chiefly in the lymph it contains, which is evidently much more animalized than the other conftituent parts of the jelly. If concentrated to fuch a degree as to give it the form of a cake, its difpofition to putrefaftion is flopped; on this principle dry or portable foups are formed. By a fimi- lar concentration of the jelly made from the parings of lea- ther, the fkins of animals, with the ears of oxen, calves, fheep, &c. are the ftrongeft glues made. With the clippings of gloves and of parchment is made^z*, ufed by plaflerers, &c. Gilders' fize is made by boiling eel-fkin with a fmall quantity of lime in water, to which fome whites of egg are jfdded : that which is employed to fortify paper, and repair its defects, is made of wheat flour diffufed in boiling water. From the mucilaginous parts, chiefly the air bladders, of a large fifh, in the Ruffian feas, is formed fifh-glue or ifinglafs, which poffeffes very ftrong agglutinating power, and is ufe- ful in ftiffening, and giving a luftre to gauzes, Sec. Ifin- glafs forms a ftrong glue, by folution in either water or alco- hol. Gelatin, Mr. Hatchett obferves, may exift in the dif- ferent degrees of tenacity and vifcidity which charaaerizi mucilage, fize, and glue, the different forms in which it ap- pears. This difference is evidently an inherent quality, and not caufed by mere infpifTation, the glue made from certain parts of animals, fuch as the fkin, being of a better quality than that which is made from the finew, and the beft and ftrongeft glue is always made from the more aged animals. Gelatin when completely dried is affeaed by water, according to its original degree of vifcidity, cold water diffolving dried mucilage in a fhort time, but only oc- cafioning a cake of glue, after fteeping three or four days to fwell much, without being diffolved. Gelatin is folu- ble in acids ; thus dry mucilage, dry fize, and dry glue, are progreflively diffolved in nitiic acid, according to the degree of vifcidity by which they are diftinguifhed. 163 There is every reafon to conclude that the fubftance which in very young animals was at firft mucilage, becomes pro- greflively more vifcid and affumes the character of gelatin, which as animals increafc in age becomes more and more vifcid. Skins of animals yield gelatin proportioned to the degree of flexibility they poffefs. Thus the fkin of the eel and the fliark yields a larg? proportion. The flcins of the hare, rabbit, calf, ox, and rhinoceros, yield fimilar refults; that of the rhinoceros yielding the ftrongeft and moft vifcid gelatin. The true fkin or cutis is completely foluble by long boiling, and feems to be effentially formed of gelatin; but the cuticle isfoftened, but not diffolved, and appears to contain gelatin only in a fmall proportion ; it is however neceffary to its flexibility, fince it becomes quite brittle when deprived of it. The cartilages of the articulations are alfo completely fo- luble when long boiled with water ; but this by no means happens when other cartilages are thus treated. Hair imparts a fmall portion of gelatin to water, lofing thereby its elafticity and flexibility, thefofteft and moft flex- ible hair yield'ng moft. Feather, quill, human nail, ox's hoof, tortoife fbell, and the fcale of a fcorpion, /hewed no trace of gelatin by the teft of the tanning principle, and but a faint white cloud with nitro-muriate of tin. Horns, fuch as thofe of the ox, ram, goat, and chamois, yield fmall quantities of gelatin, and in proportion to their flexibility. But flag's or buck's horn differ from thefe, both in compofition and conftruction ; containing, like bone, much phofphate of lime, and like bone, a large quantity of gelatin t phofphate of lime generally being ac- companied by gelatin as in flag's horn, bone, ivory, &c. but when carbonate of lime is the hardening fubftance, as in fhells, madrepores, and millepores, no gelatin can be difcovered. Scales of fifh, and the fpicula of the fharVs fkin, appear to be true boney fubftances, containing much phofphate of lime, with a greater proportion of the membranaceous part than in common bone. Horny fcales of the mantis, of lizards, ferpents, Sec. yield but very flight traces of gelatin, feeming to confift of the membranaceous fubftance merely, appearing to be devoid of phofphate of lime, as an oflifying matter. Gelatin is evidently the principal caufe of flexibility and 164 elafticity, and.the putrefcibility of various parts. ■ Philof. Tranf. 1800. The skins of animals, after wafhing, flefhing, and cleaning from the hair, are impregnated wifch the tanning principle, with which they form a compound infolubie in water, and poflefling other ufeful qualities ; this fubftance is termed leather. To render leather impenetrable by water, Mr. Hilde- brandt recommends it to be foaked in oil in which minium is diffolved and boiled to a deep brown.----Ann. de Chi. de Crell. 1799. VIII. The muscular or fleshy parts afford, by diftiilation, water, alkaline phlegm, empyreumatic oil, nitrogen gas, carbonate of ammoniac, and a coal which yields a fmall quantity of fixed alkali and febrifuge fait. Thouvenel found, in flefh, a mucous extradive fubftance, foluble in water and in alcohol; and when concentrated, poffeffing an acrid and bitter tafte. On hot coals it fwells, liquifies, and emits a fmell like that of burnt fugar: all its characters, indeed, fhow a refemblance between it and the faccharine matter of vegetables. Thouvenel alfo obtained, by a flow evaporation of the decoction of flefh, fait, in the form of down, and in cryftals of an indeterminable figure : this fait appeared to him to be a phofphate of pot-afh, in frugivorous, and a muriate of pot-afh in carnivorous, ani- mals. Fourcroy thinks thefe falts may be phofphates of fo- da, or ammoniac, mixed with the phofphate of lime. The moft abundant part of mufcles, and that which conftitutes their predominating character, is the fibrous matter. This is diftinguifhed by its infolubility in water, and by its yield;ng more nitrogen gas, by the nitric acid, than other animal fubftances. It alfo yields the oxalic and the malic acid. It putrifies readily, when moiftened ; and affords much concrete ammoniac by diftiilation. Of the other mat- ters contained in flefh, the lyrrtph, and fat part, have been already fpoken of; and the albumen has been lately the fubject of fome ingenious experiments of Mr. Hatchett. Albumen, that tenacious fluid contained in the blood, and compofing the chief part of the white of eggs, which, when dry, is femitranlparent, like horn ; is according to Mr. Hatchett, the predominant and effential part in the tiffue or web of membrane, cartilage, fponge, the horny ftems of gorgonia, horn, hair, feather, quill, hoof, nail, horny fcale, cruft, and tortoife fhell, and although of fimi- lar chemical properties, yet it varies in confiftency, from a tender jelly-like fubftance, to a completely formed mem- 105 brane, or to an elaftic, brittle and hard body, like tortoiie- fhell, manifefting a ftratified arrangement. Moreover the chemical properties of thefe fubftances refemble thofe of pure albumen, in every refpect; fo that it evidently ap- pears to be the original fubftance from which tortoife-fhell, hair, horn, mufcular fibre, Sec. have been derived and formed. Mr. Hatchett thinks there is alfo much reafbn to believe that gelatin, although it appears fo different from albumen in many refpects, is yet formed from it, and that albumen, or the coagulating lymph, is the primary animal fubftance from which the others are derived. Pure albumen which has not been fubjected to the effects of organization, appears to contain a confiderable portion of faline matter, and very little of any earthy fubftance ; but in fuch bodies, which (although derived from albumen) have fuffered various changes by the aftion of the vital principle, the quantity of faline fubftances appears to be diminifhed, while that of the earthy matter is increafed; and as lime, in the ftates of phofphate and carbonate, is fo much more abundant in the mufcle of beef than in that of veal, we may infer, that the earthy matter is more abundant in the coarfe and rigid fibre of adult and aged animals, than in the tender fibre of thofe which are young. There appears much reafon, Mr. Hatchett fays, to be- lieve that the gelatinous fubftances and mufcular fibre, dif- fer from fimple and unorganized albumen, by a diminution of the carbonic principle in the one, and by an excefs of it in the other, the mufcular fibre containing by much the great- eft quantity : refembling, in that refpect, the vegetable fibre. In refpect to economical purpofes, Mr. Hatchett ob- ferves, that all animal fubftances whatever (exclufive of carbonate and phofphate of lime) may be converted into two fubftances of much.utility, glue and foap ; the gelatin yielding the one and the albumen the other.-----Phil. Tranf. 1800. Fourcroy found the mufcular parts of bodies, which had been interred in the Cemeterie des Innocens, converted into a fubftance refembling f'permaceti.-----Annales de Chi- mie. v. Lord Bacon, in his Sylva Sylvarum, ftates, that fuch a change may be effected, by putting pieces of flefh into a glafs covered with parchment, and allowing the g'afs to ftand fix or feven hours in boiling water.. 166 Thomas Sneyd, efq. of Staffordfhiie, found in the mud, at the head of a fifh pool, the body of a duck or young goofe, converted into a hard fatty matter refembling fper- maceti ; having apparently fuffered a fimilar change with that of the human bodies, obferved by M. Fourcroy, in the Cemeterie des Innocens.-----Phil. Tranf. 1792. Mr. G. Smith Gibbes, having placed the leaned part of a. rump of beef in a box with holes, fo as to float on the fide of a river, found, at the end of a month, it was converted to a mafs of fatty matter. He alfo found a piece of lean mutton en which nitrous acid had been poured, three days before, to be exactly the fame with fome which he had before got from the water, and which, though changed, was not fo much fo as the beef.-----Phil. Tranf. 1794. Mr. Gibbes further remarked, that the fatty matter form- ed from the flefh of quadrupeds, does not crydallize, whilft that from the human fubjeft affumed a very regular and beautiful cryftalline appearance. To purify this matter he expofed it to the fun and air, for a confiderable time, reduced it to powder, and poured on it diluted nitrous acid, this remaining on it an hour ; he then wafhed it repeatedly, and finally melted it with hot water, and, on allowing it to concrete, it was of a beautiful ftraw colour, and had the agreeable fmell of the beft fpermaceti.-----Phil. Tranf. '795- Dr. Crawford, by his ingenious experiments, difcovered, that cancerous matter renders fyrup of violets green, and" that, with oil of vitriol, effervefcence takes place, and the mixture becomes of a dark brown, a gas being difengaged, which has many of the properties of hepatic air, and which the doftor called, animal hepatic air. This he found to be mixed, in the matter, with volatile alkali, forming an hepa- tifed ammonia, which may occafion the black depofition from the folution of fublimate, when employed to wafhve- neieal ulcers in the throat; on faturnine poultices appliedto ill-conditioned ulcers; and on filver probes introduced into finous ulcers. The animal fibres undergoing, in cancer- ous and other malignant ulcers, nearly the fame changes which are produced by putrefaction, or deftruftive dif- tiilation. Lean animal fubftances yield, by heat, alkaline air, carbonic acid, and animal hepatic air, from which fome- times is depofited an oily empyreumatic /ubftance, a dimi- nution of the volume of the gas, at the fame time, taking place. It feeming probable,, the doftor thought, that thefe 167 three aerial fluids combining together, formed the oily em- pyreumatic fubftance. The aerial fluids extricated from the mufcular fibres of animals by putrefaftion, confift of carbonic acid and ani- mal hepatic gas, mixed with a very fmall proportion of phlogifticated air. From the green leaves of a cabbage, I obtained, the doftor fays, an aerial fluid, which, in moft of its properties, refembled animal hepatic air. Phil. Tranf. 1790. Vauquelin found that ammonia was produced by the action of fulphuric acid on animal fubftances. Mr. Jamefon found that the mufcular fibre of fifh, treated with pure alkali, yielded ammonia, efpecially with long boiling and the addi- tion of tallow; a carbonaceous matter fubfiding, not afted upon by alkalies. Thus the mufcular fibre appears to be completely decompofed, its hydrogen and nitrogen forming ammonia, and the carbonaceous matter being left behind.— Jamefon s Experiments. IX. Urine is an excrementitious fluid, fecreted by the kidneys; in its natural ftate, it is tranfparent, of a peculiar fmell, a citron yellow colour, and a faline tafte. Bcfides the differences proceeding from peculiarity of habit, there are other differences in the urine, arifing from other cir- oumftances. That which is voided foon after copious drink- ing, is aqueous; having hardly colour or fmell, and is called crude urine, or urina potus: whereas that which is made after the fanguification, fucceeding to a full meal, poffeffes all the characters of urine, and may be called the faces fanguinis. By the fpontaneous decompofition of urine, it foon lofes its original fmell, and acquires that of ammonia; which being alfo diffipated, the fmell becomes very fetid and offenfive, and the colour brownifh : in this ftate it mani- fefts much lefs acid than when frefh (Halle). The crude urine prefents very different phenomena, becoming foon covered with mouldinefs, like the expreffed juice of vegetables. By diftiilation, the urine yields a phlegm which foon pu- trifies, and which affords ammonia by its putrefaction. At the fame time, a fubftance is precipitated of an earthy ap- pearance, but which is, in reality, a peculiar faline fubftance. This fait forms the fediment of urine, which feparates by the cold, or by evaporation, even in the urine of perfons in perfect health. By evaporating urine to the confiftence of a fyrup, and allowing it to ftand in a cool place, cryftals are formed. 168 This precipitate of cryftals has been called fufible fait, na- tive fait, and microcofmic fait. It is chiefly compofed of the phofphate of foda and of ammoniac, and is ufed as a flux to the earths. From accurate experiments it appears that thirty-fix ounces of urine yields a refiduum from an ounce to an ounce and a half, which confifts of the following ingredients in nearly thefe selative proportions. Drams. Grains. Muriatic falts................i 0 Phofphoric falts...............3 jo Lithic or Uric acid and phofphate of lime, l with excefs of acid.......• • 3 ° Z* Animal extractive matter......... . 3 40 The falts are the muriates of pot-afh and of foda; the phofphates of foda, of lime, and of ammonia, with the lithic and phofphoric acids.----Cruikfhank. Urine, when firft voided, contains an excefs of phofpho- ric acid, and thereby holds in folution more or lefs of phof- phate of lime. It foon runs into the putrefactive ftate, ac- companied with the extrication of much ammonia. The ammonia is difengaged from urine, likewife, by the fixed alkalies and lime, which decompofe the phofphate of am- moniac ; and acids diminifh its fmell by combining with and fixing the ammonia, which is the principal caufe of its odour. The urine of animals which feed on vegetables does not appear to contain phofphoric acid, but an acid of a vegetable nature, which feems to refemble the benzoic— Rouelle and Fourcroy. Recent human urine contains ten conftant ingredients; muriate of foda, muriate of ammoniac, acid phofphate of lime, phofphate of magnefia, phofphate of foda, phofphate of ammonia, uric acid, benzoic acid, jelly, albumine, and the fpecific matter of urine, called uree, to which matter the urine owes its odour, colour, and favour, its alterability into ammonia, carbonic and acetic acids, Sec. with the property of becoming by putrefcent fermentation, a fluid fo different from what it is when firft voided, as to contain nine new ingredients. Thefe are, 1. Ammonia in excefs. 2. Phofphoric acid faturated by this alkali. 3. Phofphate of magnefia, converted into ammoniaco-magnefian phof- phate. 4. Urate of ammonia. 5. Acetous acid, united to ammonia. 6. Benzoic acid with ammonia. 7. Muriate of foda, changed in its cryftallization from the cube to the oftaedron. 8. Muriate of ammoniac, changed from the octaedron to the cube. 9. Carbonate of ammoniac. 169 The uree is obtained by diftiilation from a brown liquor Formed, by adding at different times, four times their weight of alcohol, on the cryftals yielded by infpiffated urine.---- Ann. de Chim. 93. According to Fourcroy, the analyfis of urine difcovers that it contains the phofphoric, uric, and benzoic acids, in a free ftate, the phofphates of lime, of foda, of magnefia, and ef ammoniac, and a peculiar cryftalline matter in the form of an extract, which is the moft abundant of all the matters it contains ; and which poffeffes the very fingular property of changing to carbonate of ammoniac by the aftion of fire, and alfo of changing the cubic cryftals of the muriate of" foda into oftahedra, and the oftahedra of the muriate of ammoniac into cubes. This animal matter, named uree, is an excrementitious fubftance furcharged with nitrogen, and it is by it that the body rids itfelf of the fuperfluous part of this animalizing principle. The urine fuffers a fpontaneous decompofition, thereby undergoing very con- fiderable alterations, its falts being changed and multiplied, and the acetous and carbonic acids, with ammoniac formed. Befides the ammoniaco-magnefia phofphate, and the phof- phate of ammonia, the carbonate of ammoniac is produced in a confiderable quantity, and is eafily obtained by diftiila- tion.——Tab. Syn. de Fourcroy, 1800. Phosphorus is thus obtained from URINE. Ten pounds of urine evaporated to the confiftence of honey, the muriate of lead, remaining after th,e diftiilation of four pounds of minium, two of muriate of ammoniac, and half a pound of charcoal, are to be mixed together, and dried in an iron pot, until reduced to a black powder, which is to be deprived of its volatile alkali, fetid oil, and muriate of ammoniac, by diftiilation ; the refidue containing the phof- phorus, which it will yield, by diftiilation in a good earth- en retort. In this procefs the muriate of lead is employed, to decompofe the phofphate of foda, which is not decompo- fable by charcoal, and to form the phofphate of lead, which affords the phofphorus.——Margraaf. Phofphorus is of a flefh colour, of the confiftence of wax, and at firft tranfparent, but becoming white, and, in the fun, yellow. In the air it emits a white fume, and is lumi- nous in the dark. It is foluble in oils, more efpecially in volatile oils, which then become luminous : the oil of cloves is ufed for this purpofe, and every time the bottle is opened a phofphoric flafh is feen. A phofphoric gas may be extract- ed from phofphorus, which takes fire by the mere contaft of air. Thus the nitric acid being digefted on phofphorus, a P 170 igasefcapes, whicfh takes fire in the receiver, affording the appearance of flafhesof lightning ftriking through the cavity of the veffels. Avery thin flice of phofphorus being placed on an anvil with a gros of the cryftals of nitrate of filver, and fmartfy ftruek with a hammer, a moft terrible detonation was pro- duced, the edge of the hammer was turned up, and the anvil fhaken and marked with ftreaks of'filver. The lapis infernalis and all the metallic nitrates being thus treated, violent detonations were produced. The experiment alfo fucceeded with the common nitrate of pot-afh, but the ham- mer was required to be heated.----Bmgnatelli. Van Mons repeated thefe experiments with'fuccefs, and found-the oxides of gold, filver, and mercury, by fire, to occupy the firft rank among fulminating fubftances. He .alfo difcovered that two grains and a half of oxygenated muriate of ammoniac, with four grains of phofphorus, be- ing gently crufhed on the anvil, a moft terrible detonation ensued, which alarmed the houfe ; and the concuffion was fo violent as to force the hammer out of his hand.____Ann. deChim. 1797. Phofphorus precipitates fome metallic oxides from their folutions, in a metallic ftate, and the phofphoric acid is formed; the oxygen quitting the metal to unite with the phofphorus. Phofphorus is not luminous in pure nitrogen gas, as was maintained by Prof. Go'e'tiling ; the prefence of cxygen ap- pearing to be neceffary to produce this effeft. Jacques, Hei- di brand, Van Mons. At about ioo° of Fahrenheit, it takes fire with decrepi- tation, burns with a very bright flame, and emits a very abundant white fume, which is luminous in the dark. The refidue of the combuftion is a red cauftic fubftance, which, attrafting the humidity Of the air, is diffolved into a liquor. Brugnatelli remarks, that phofphorus diffolves wirhont light in oxygen gas, which becomes luminous by adding any mephitic gas. It diffolves alfo in hydrogen, and is then feparated by oxygen. It feparates the oxygen from the oxy-muriatic acid, and becomes itfelf an acid, fjut does not diffolve in pure carbonic acid. When the temperature is a little raifed, and fome pure air is added, it fhines better than in atmofpheric air. Water fufpends little atoms of phof- phorus only. Atmofpheric air diffolves it at the moment of burning, and becomes phofphorefcent.——Ann. de Chim. •xxjii. 171 Gren fays, thaV phofphorus not fhining in pure oxygen air, but requiring a little portion of nitrogen, is owing to the fame realbn that other fubftances, fuch as fulphur, re- quire the medium of fome other fubftance, to enable them to attraft oxygen. Girtanner conjeftures phofphorus to be hydrogen in its pureft ftate. The p-HOSPHoRic Aero is formed by the combination of oxygen with the phofphorus during combuftion. This acid thus obtained is, however, imperfect, not being fatu- rated with oxygen ; but the phofphorus is more completely decompofed by the flower combuftion, or combination with oxygen, which takes place at the common temperature of the atmofphere ; fluid acid of phofphorus is thus obtained^ ftill however retaining a fmall quantity of undecompofed phofphorus, of which it may be cleared by digefting alcohol upon it. By digeftng nitric acid upon phofphorus,. nitrous gas is feparated and the oxygen unites to the phofphorus, forming phofphoric acid. If the acid be highly concentrated, the phofphorus burns at the furface. The water in which phofphorus is kept, contrafts acidity in time, the water yielding its oxygen to the phofphorus. This acid, when pure, is clear, inodorous, and not corrofive; it may be concentrated to drynefs, when its fpecific gravity, compared with water, is as 3. 1. It is very fixed, If after concen- tration it is put in a crucible, on hot coals, it boils, a green flame appears, and the mafs is converted into,a white tranf- parent fubftance foluble in water. The phospha.tf. of pot-ash forms a very foluble, farr> in tetrahedral cryftals, terminating in tetrahedral pyramids ; is acid, fwells on hot coals, is difficult of fufion, and.de- compofable by lime water. Phosphate of soda forms in rhomboidal cryftals which efflorefce in the air. This like the-former phofpha'e melts into a glafs when ignited. It has been introduced into medicine by Dr. Pearfon, as a ufeful and almoft taft«»- lefs cathartic. Phosphate of ammonia.formsrin tetrahedral cryftals, readily foluble in water. It is alfo fufible, when it parts- with its ammoniac Phosphate of magnesia, is difficult of folution, but becomes more eafily foluble, cryftallizable, and fufible, the more it contains of phofphoric ac d. Phosphate of baryt is taftelefs and infolubie^, and convertible by fire into a glafs„ 112 Phosphate of strontia is foluble, when the acid is in excefs, and forms tabular cryftals. In fire it fufes into a mafs like porcelain. Phosphate of lime is white, friable, infipid, opake, and infolubie in water. Phofphate of lime, apatite orphofphorite, has been found in an amorphous ftate in Hungary, and forming entire mountains in Spain. It is alfo found in truncated hexhe- dral, longitudinally ftriated prifms, laminated in their tranfverfe fracture, and generally with tin and fluor. Klap- roth found it to contain acid 45, lime 55. The chryfolite is alfo confidered as a faline combination of this fpecies. Phosphate of alumine forms in thin flattened needle-like cryftals, obliquely truncated at both ends. It deliquefces in the air, and, in a melting heat, fufes into glafs. X. The calculus of the bladder is chiefly formed of a peculiar concrete acid, which is flighily foluble in boiling water, and is depofited in cryftals, as the folution tools. The uric acid, or acid of calculi, formerly called the lithic acid, is concrete, fparingly foluble in water, and is decompofed, and partly fublimed by diftiilation : it decomi pcfes the nitric acid, unites with earths, alkalies and metal- lic oxides, and yields its bafes to the weakeft vegetable acidt, not excepting the carbonic. Mr. Lane afcertained by careful experiments that there ■ exifts a great difference in different calculi, fome being dif- folved in the lixivium faponarium, and others beingfcarcely altered ; fome retaining their form, whilft others were near- ly evaporated by a red heat. Different parts of the fame cal- culus varying confiderably in thefe refpefts.——Phil. Tranf. J791- 11 has been afcertained that the calculus, jft. Is diffolved by the fulphuric acid, with heat. 2. Is not afted on by the muriatic acid. 3. Is diffolved by the nitric acid, with effer- vefcence and the difengagement of the nitrous gas and car- bonic acid : the folution is red, contains a difengaged acid, tinges the (kin of a red colour, and is not precipitated by the muriate of barytes, nor rendered turbid by the oxalic acid. 4. Is not acted on by the carbonate of pot-afh, but is dif- folved by the cauflic alkali, as well as the volatile alkali. 5. is diffolved in lime-water in the quantity of 5,37 in 1000 grains, and may be precipitated by acids. 6. Contains a fmall quantity of ammoniac. 7. The coally refiduum of combuftion indicates an animal fubftance of the nature of jelly.-----Scheele. This iliuftrious chemift has alfo proved that all urine, even that ot infants, holds a fmall quantity of" the matter of calculus in folution, and that the brick coloured depo* fition from the uri ne in fevers j is of the nature of calculi, but he did not find that it contained a particle of calcareous earth. By pouring the fulphuric acid'into the nitrous folu- tion of the calculus, a true fulphate of lime was obtained ; although the lime did not exceed the200th part of the entire weight.- This chemift alfo detected a white fpongy fubftance, not foluble in water, fpirit of wine, acids, or alkalies, nor in the nitric acid, even in the ftate of afhes ;*but the quantity was too fmall to be thoroughly examined. The matter obtained from calculi, by folution in lye of cauftic fixed alkali, and-precipitation by acids, has been fuppofed to be an acid fimilar to that obtained by fublima- tion, and which has been termed lithic ach>; Dr. Pearfon obtained this precipitate, in the proportion of at leaft one half of the matter of the calculi; and afferts that this precipitate does not belong to the genus of acids ; that it is not the fame thing as the fublimate of Scheele, nor is to be referred to th-i animal mucilages ; but that it belongs to the genus of animal oxides. Its peculiar and fpecific dif- tin^utfhing properties being imputrefcibility, facility of cryftallizationv infolubility in cold water, and that mod .remarkable property of all others,,of producing a pink cr red matter, on evaporation of its folution in nitric acid. Of 300 grains of calculus 175- were this peculiar animal oxide, 96 were-pbofpfrate of lime, 29 were ammoniac and probably united with it, phofphoric acid, water, and comr man mucilage, of urine. The term lithic, being,- the doctor fays, a grofs fole- cifm, be propofes, as more appropriate, the term ouric or uric. This oxide he would therefore term the uric OXIDE. From 100 grains of an urinary concretion he obtained only 1 8 grains of the acid fublimate of Scheele, and doubts whether the lithic acid of Scheele exifts as a conftituent of urinary concretions, or is compounded, in confequence of a new arrangement of the elementary matters of the concre- tion, by the agency of fire. The doftor did not find the uric oxide in the urinary concretions of any phytivorous animal. , ■ •Phil. Tranf. 17 9 7 • 174 Fourcroy afferts that Scheele did not give the name of lithic acid to the fublimate of the calculus, as Dr. Pear- fon afferts, and that the peculiar animal oxide of Dr. Pearfon is really Scheele''s acid (the lithic acid). Fourcroy approves of the adoption of the name ouric acid, efpecially as Dr. Pearfon has found the fame acid in athritic concre- tions, and it has not yet been found, but in man. Ann. de Chim. xxvn. Although the caufes of difeafe, thefe concretions are the natural produfts of urine, which generally contains almoft all the materials of which they are compofed. Thefe may be formed by i. Uric acid, which cryftallizes in ftriated layers, is in- folubie in cold water, and but flightly foluble in hot, it weakly reddens turnfole, is infipid, inodorous, foluble in cauftic alkali; when pure, of a fawn colour, and becoming of a pink red by the addition of nitric acid. 2. Phofphate^ of lime, this will be found to concrete in earthy layers refembling chalk, to be foluble, without ef- fervefcence, in nitric acid ; precipitable by all the alkalies; by the fulphuric acid in a fulphate of lime, and by the oxa- lic acid is an oxalate of lime. 3. Ammoniaco-magnefian phofphate, forms in femitranf- parent, fpathofe, hard layers, fufceptible of polifh, or in cryftals, very foluble in all the acids, yielding an ammonia- cal vapour by the addition of fixed alkalies, which deprive it of the phofphoric acids. It is often mixed with the phof- phate of lime, and frequently covers a kernel of uric acid or oxalate of lime. 4. Oxalate of lime forms the harder, mulberry form, calculi, which are very denfe and capable of receiving a fine polifh, are externally of a footy brown colour, inter- nally of a dirty grey, having numerous tubercles on their furface, are infolubie in water, very difficultly foluble in the nitric acid, and not affefted by alkalies, leaving, after the aftion of the fire, which burns the animal matter, a refi- due of quick-lime. Befides thefe four fubftances, which are united to a gela- tinous or albuminous animal matter, filica is fometimes, but very rarely, found in the human urinary calculi.------■ Tabl. Synopt. de Fourcroy. 1800. Dr. Pearfon found the uric acid in arthritic concretions : Mr Tennant difcovered in them a combination of that acid and foda. Fourcroy and Vauquelin confirm this analyfis, finding them to confift of urate of foda, with a confiderable quantity of animal matter. 175 XI. The prussic acid, or colouring matter of pruffian blue, is produced by expofing the horns, hoofs, or dried blood of animals, with an equal quantity of fixed alkali, to a red heat. The alkali united with the acid thus formed, yields a fait in tetrahedral plates, or prifms, with tetrahe- dral fummits, which is called prussiate of pot-ash, or of soda, according to which alkali has been employed. Thefe prufliates of alkali precipitate all metals from their folution ; the alkali uniting with the acid which held the metal in folution, whilft the pruffic acid unites with the metallic oxide, and communicates to it a peculiar colour. Thus gold is precipitated of a yellow; lead of a white; copper of a brownifh red; and iron of a dark blue, being a prusssiate of iron, or the fubftance called pruffian- blue. The pruffic acid may be again feparated from pruffiate of iron, by digeftion with pure alkali, the pruffiate of alkali, being again formed, and the iron left in a brown oxide. Thus may a tully faturated pruffiate of pot afh be obtained ; but ftill this is not a pure pruffiate, but contains fome iron or rather pruffian blue, which it depofits on the addition of an acid, and therefore it is not an accurate teftof the quantity of iron contained in any folution. In thefe prufliates, in confequence of the volatility of the acid, a part of the alkali exifts in a crude ftate, unneu- tral zed ; hence the precipitate of iron has a greenifh caft from the yellow precipitate thrown down by this unfaturated alkali. This laft precipitate is foluble by an acid and the other is not; therefore the addition of an acid to it gives it its full blue colour, and on the fame principle the pruffiate may be previoufly faturated with dilute fulphuric acid. Sulphate of alumine is profitably employed in the precipi- tation of pruffian blue, its earth increafing the quantity : it may be deprived of this by digefting it with muriatic acid. The pruffic acid is obtained in a pure ftate, by fuperfatu- rating the pruffiate of alkali with fulphuric acid, and by fubfequent diflillation. It may alfo be obtained by diftiila- tion of blood with nitric acid. It has an acid tafte and fuf- focating fmell; but except its capacity of combining with alkalies and metals, it manifefts no confpicuous acid pro- perties. By digeftion of pruffiate of iron with ammonia, the prus- siate of ammonia is obtained, and, in the fame manner, is prussiate of lime obtained with lime water. This acid is found alfo in the mineral kingdom, combined with ITS iron ; it alfo exifts in vegetables. The pruffic colouring principle has been obtained by pafling ammoniacal gai through charcoal.-----Cloutt. 5 Prouft defcribes pruffian blue-to be an oxide, whofe bafis- contains 4S-100. of oxygen. Berthollet believes its bafis to be compofed of hydrogen, nitrogen, and carbon ; but its conftituent parts are not yet known. r3uIIi-i7!he B0MBIC ACID is f°und to exift in all the ftates of the filk worm, in all its ftagea of exiftence, even in the eggs ; but in the egg and in the worm, it is combined with a gummy glutinous fubftance.—Chauffer. _ XIII. Hartshorn gives name to feveral products ufed in medicine, which though the preference is given to this horn, may be yielded by any other. By diflillation an alkaline phlegm is firft procured, which is called the vola- tile fpirit of hartfhom.; a reddifh oil next comes over, more or lefs empyreumatic, this rectified, is the animal oil ofDip - pie; then rifes a confiderable quantity of the carbonate of ammonia, coloured by the oil, but from which it may be purified to a beautiful decree of whitenefs. Thecoally re- fiduum contains foda, with fulphate and phofphate of lime, from the latter of which phofphorus may be obtained. Burnt entirely to an afh, it is the calcined hartfhornof the fhops. XIV. Bones confift chiefly of jelly, fat,,and an earthy neutral fait. By diftiilation they yield hydrogen and carbo- nic acid gas, a volatile alkaline liquid, an-empyreumaticoil and dry mild ammoniac, the refiduum is a coal, which, when obtained with certain precautions, is ufed in the arts, and is called ivory black By open combuftion this coal is reduced to afhes, which, unlike the afhes of vegetables,: manifefts no marks of fixed>alkali. The earth of calcined bones was difcovered in 1769, to confift of lime united with the acid of urine (Gahn.) It was then difcovered, that by decompofing this fait of bones by the nitric and fulphuric acids, evaporating the refidue, which contains the phofphoric acid in a difengaged ftate, and diftilling the extract, with powder of charcoal, phofphorus was obtained.-----Scheele. Pulverized burnt bones are to be mixed with half their weight of fulphuric acid, and after digefting two or three days, water muft be added and the mixture digefted ftill farther on the fire. The water of the lixivium, aa well as the water with which the refiduum is wafhed, to deprive it of its falts, is then to be evaporated in veffels of ftone ware, until it affords an extract, which muft then be diffolved in 177 the leaft poffible quantity of water, and filtered, that the ful- phate of lime may be feparated. This extraft may be then put in a large crucible, and the fire urged; when it fwells up, but at laft fettles, and at that inftant, a white glafs, of a milky hue is formed*, which mixed with an equal quanti- ty of charcoal, and diftilled in a porcelain well coated retort, yields the phofphorus by diftiilation. The theory of this operation may be thus explained. During the combuftion of the bones, oxygen combining with the proper radical, forms phosphoric acid, which with the lime generates phosphate of lime. Carbonate as well as pruffiate of lime being alfo formed in the fame man- ner, and at the fame time. The phofphoric acid here is confidered by Gren as a produd of combuftion and not real- ly an edud. But to return to the explanation of the procefs —the phofphoric acid is then difplaced from the phofphate, by the fulphuric acid, which forms with the lime, fulphate of lime. By the fucceeding operations, the fulphate is fepa- rated, and the acid is concentrated. By the diftiilation with charcoal, the phofphoric acid is decompofed; its oxygen unites with the coal, and affords carbonic acid, while the PHOSPHORUS itfelf is difengaged. The phofphorus may be purified, by being immerfed in a veffel of boiling water; as the phofphorus melts, and may be paffed through a niece of chamois leather like mercury. The lower orifice of a funnel being flopped, phofphorus with wa- ter is to be put in it, and the funnel plunged in boiling wa- ter ; as the heat is communicated the phofphorus melts, runs into the neck of the funnel, and takes that form ; when cold it is to be thruft out of its mould, and kept under wa- ter : it leaves, according to Prouft, a reddifh phofphuret of carbon on the leather. Ann. de Chim. C. 103. XV. The enamel of teeth, according to the very in- terefting experiments of Mr. Hatchett, diffolved without heat in muriatic acid, depofits felenite by the addition of fulphuric acid ; after which the remaining fluid is render- ed thick and vifcid by evaporation. This when diluted with water, precipitates lime from lime water, in the ftate of phofphate. Acetite of lead alfo precipitates a white matter, which produces a light and fmell, on burning charcoal, like phofphorus, and is foluble in nitrous acid; whereby it is • Becher, who was acquainted with this glafs of bones, fays, " homo vitrum eft, et in -vitrum redigi pot eft. A fkeleton of nineteen pounds, yields five pounds of phofphoric glafs. ITS diftinguifhed from muriate or fulphate of lead. Enamel be- ing alfo diffolved in nitric acid, and the folution faturated with carbonate of ammonia, a precipitate is formed, com- pofed of lime combined with a portion of phofphoric acid : phofphoric acid is alfo precipitated from the remaining fluid, by folution of acetite of lead. The enamel is therefore not a carbonate, but a phofphateof lime. Lime and phofphoric acid appearing to be the effentially condituent principles of tnamel; the enamel appearing to differ from tooth or bone, by being deftitute of cartilage, and by being principally rormed of phofphate of lime, cemented by gluten. XVI. Shells, according to the fame celebrated chemid, as- to the fubdance of which they are compofed, are porcellane- ous, with an enamelled furface, and when broken, often of fibrous texture ;. or are compofed of nacre or mother of pearl. It appears that the porcellaneous fhells are compofed of car- bonate of lime, cemented by a very fmall portion of gluten ; and that mother of pearl and pearl do not differ from thefe, ex- cept by a fmaller portion of carbonate of lime ; which in- ftead of being fimply cemented by animal gluten, is inter- mixed with, and ferves to harden, a membranaceous or car- tilaginous fubdance; and this fubdance even when deprived ef the carbonate of lime, dill retains the figure of the fhell. Thefe fhells appear to be formed of various membranes ap- plied flratum fuper flratum, each membrane having a cor- refponding coat, or crud of carbonate of lime. The inhabi- tants of thefe ftratified fhells increafe their habitation by new ftrata, each flratum exceeding in extent thofe which were previously formed, the fhell becoming ftronger in propor- tion as it is enlarged, and its number of ftrata denoting its age. Tooth and bone being fteeped in acids, the oflifying fubftance* are diffolved ; the enamel of the tooth is com- pletely taken up by the acid, while the cartilage of the boney part of the tooth is left, as is the cafe with other bones, re- taming the fhape of the tooth, and a cartilage or membrane of the figure of the bone remains. Thefe effefts, as well as thofe from expofure to fire, fhow a fimilarity between enamel and the porcellaneous fhells, as well. a3 between the fub- ftance of tooth and bone, and" fhells compofed of mother of pearl. Thus poicellaneous fliells refemble enamel, in fuf- iei ing a complete diffolution in acids, and not leaving any pulpy or cartilaginous matter; whilft fliells of nacre, like bone, and the fubftance of tooth, part with their oflifying fubftances in certain acids, and their bafes remain in the ftate of membrane or cartilage. The bafis, varying, in different fliells, and in different bones, in its degrees of infpifTation,, 179 from a very attenuated gluten to a tough jelly, and from this to a perfeftly organized membrane compofed of fibres, arranged according to the configuration of the fhell or bone. The cuttle bone of the fhops, appears in compofition exaftly to refemble fhell, it confiding of various membranes, hardened by carbonate of lime, without the fmalled mixture of phofphate. The crust of the echinus approaches moil nearly to the fhells of the eggs of birds, confifting of carbonate, with a fmall proportion of phofphate of lime, cemented by glu- ten. The asterias rubens manifefts a portion of carbonate of lime, without any mixture of phofphate, but in the as- terias papposa a fmall quantity ofif phofphate, of lime is difcovered. In the cruftaceous covering of marine animals, fuch as the crab, lobfler, prawn and cray-fifh, carbonate and phofphate of lime, but the former in the largeft proportion, are found. Phofphate of lime mingled with the carbonate, appearing to be the chemical charafteriftic which diftin- guifhes the cruftaceous from the teftaceous fubftances. The prefence of phofphate of lime evinces an approximation to the nature of bone, which confifts principally, as far as the oflifying fubftance is concerned, of phofphate of lime. By thefe ingenious inveftigations of Mr. Hatchet, carbonate of lime was alfo difcovered to enter into the compofition of bones ; but as the carbonate exceeds in quantity the phof- phate of lime, in egg-fhells and cruftaceous animals, fo in bones it is the reverie. It is poflible that, fhells containing only carbonate of lime, and bones containing only phofphate of lime, will form the two extemities of the chain. Bones of fifh appear to contain moreof the cartilaginous fubftance, and lefs of the phofphate of lime, then is commonly found in the bones of quadrupeds. XVII. Cartilage, and fuch horns as are diftinftly feparate from bone, as are thofe of the ox, the ram, chamois, alfo tortoife-fhell, contain phofphate of lime, but in two fmall a quantity to be confidered as one of their conftituent princi- ples. 500 grains of the horns of an ox yielding only 1,50 grains of refiduum, lefs than half of which is phofphate of lime. Buck's or flag's horn, has every chemical character of bone, with fome excefs of cartilage. By experiment 011 dry hog's bladder, it appears that phofphate of lime is not an effential ingredient of membrane. The bones of the Gibraltar rock confift principally of phofphate of lime; and the cavities have been partly filled 180 by the carbonate of l,me, which cements them together. Jolhl bones refemble bones which by combuftion have been deprived of their cartilaginous part, retaining the figure of the original bone, without being bone in reality, as one of the moft effential parts have been taken away. The deftruftion or decompofition of the cartilaginous parti ot teeth and bones in a foflil date, mud have been the work of a very long period of time, unlefs accelerated by the ac tion of fome mineral principle; for after deeping in muriatic acid, the os humeri of a man, brought from Hythe, in Kent and laid to be taken from a Saxon tomb, the remaining car- tilage was found nearly as complete as that of a recent bone Mr. H. quedions, if bodies confiding of phofphate of lime" like bones, have concurred materially to form drataof lime- ltones or chalk ; for it appears to be improbable that phof- phate is converted into carbonate of lime, after thefe bodies have become extraneous foffils. Gloffbpetrx alfo yielded phofphate and carbonate of lime, the latter appearing to be derived from the calcareous drata which had inclofed them and which had taken the place of the decompofed cartilage ----Mr. Hatchett, Phil. Trans. 1799. 5 • XV£n' Madrepore and millepores, like the va- rious fliells, appear from the experiments of the fame gen- tleman, to be formed of a gelatinous or membranaceous lubftance hardened by carbonate of lime ; the only differ- ence being in the mode according to which thefe materials have been employed. So completely the fame is the nature of thefe bodies, that all the changes or gradations obferva- ble in fhells are difcoverable in thefe. Tubipora mufica re- fembles the foregoing. Fluflra foliacea, and Corallina opuntia, contain alfo a fmall portion of phofphate of lime • their membranaceous part refembling that of certain madre- pores and millepores. Ifis ochracea, and Ifis Hippuris, are formed of regularly organifed membranaceous, cartilaginous, and horny fubdances, hardened in the latter, merely by car- bonate of lime, and in the former, by the addition of a very fmall portion of phofphate of lime. Gorgonia nobilis holds alfo a fmall portion of phofphate, but its membranaceous part is in two dates, the interior being gelatinous, and the external a membrane completely formed. Gorgonia cera- tophyta, flabellum, fiberofa, pedinata, andfetofa, confid of two parts, the horny dems and the cortical fubdance. The horny fubdance of the dems is found to contain a quantity of phofphate of lime, but fcarcely any trace of carbonate, and by maceration in diluted nitric acid, this fubdance be- comes foft and tranfparent, refembling a cartilagnous body-; 181 the cortical part, on the contrary, conftfts principally of carbonate of lime, with little or none of the phofphate, and is depofited on a foft, flexible membranaceous fubftance, which feems much to approach to the nature of cuticle. Gorgonia antipathes was found to be entirely formed of a fibrous membiane ; and the black, fhininggorgonia, afford- ed by maceration a beautiful fpecimen of membranes concen- trically arranged. A Gorgonia refembling the antipathes^ and fimilar to it in the membranaceous part, held fo large a portion of phofphate of lime, as to approach to the nature of ftag's or buck's horn. Sponges appear to be complete- ly formed, by a membranaceous fubftance, refembling that of the horny ftems of the gorgoniae, varying in conftruftion rather than in compofition. Alcyonium afbeftinum, ficus, and arboreum are found to be compofed of a membranaceous part, fimilar to the cortical part of fome of the gorgonia, and, in like manner, flightly hardened by carbonate, with a fmall portion of phofphate of lime. It appears, therefore, that the varieties of bone, fhell, coral, and the numerous tribe of zoophytes, only differ in compofition by the nature and quantity of the hardening or oflifying principle, and by the ftate of the fubftance with which it is mixed or connected. For the gluten or jelly which cements the particles cf carbonate or phofphate of lime, and the membrane, cartilage, or horhy fubftance, which ferves as a bafis, in and upon which the oflifying matter is fecreted and depofited, feem to be only modifica- tions of the fame fubftance, which progreflively graduates from a vifcid liquid or gluten, into that gelatinous fubftance which has fo often been noticed, and which again, by in- creafed infpiffation, and by the various and more or lefs perfeft degrees of organic arrangement, forms the varieties of membrane, cartilage, and horn. The membranaceous part of all thefe fubftances, fliells, madrepores, fluflra, Sec. was diffolved in lixivium of cauftij pot-afh, and formed animal foap,——Philof. Tranf. 1800. XIX. Synovia appears to contain lymph, muriate of foda, carbonate of foda, and phofphate of lime ; the latter, Mr. Hatchett found, but in a fmall quantity, 480 grains not yielding more than one grain. It can therefore be hard- ly confidered as one of its conftituent principles. XX. Tears are fecreted by the lachrymal glands, and are chiefly compofed of a peculiar kind of mucilage, com- mon fait, phofphate of lime, phofphate of foda, and foda, in a free and apparently cauftic ftate.----Jacquin. 182 H.XI. Mucus of the Schneiderian membrane. At its firft fecretion is analogous to the tears, but changes by ie- maining in the nofe, probably from the oxygen it i mbibes from theinfpii-ed air, and the carbonic acid of the expired air, faturating the free foda. XXII. Saliva is fecreted by its appropriate glands in the neighbourhood of the mouth ; it does not appear to differ in its conftituent parts from mucus, except in contain- ing a greater quantity of water; and fome phofphate from which concretions are fometimes foimed in the dufts or glands, and perhaps the tartar on the teeth, both being of a boney nature.----Fourcroy. XXIII. Pus is fecreted from veffels which are under the influence of .fame morbid change. It appears by its analyfis .to differ very little in its conftituent parts from mucus : it is however, faid to undergo the acid fermentation, while the former becomes putrid (Salmutb.) Mixed with an equal quantity of a faturated folution of carbonated pot-afh, pus, it is faid, will difengage a tranfparent tenacious jelly, but mucus will not. XXIV. Semen, its conftituent parts appear to be water, animal mucilage, phofphate and muriate of foda, cauftic foda, and phofphate of lime -. the latter cryftallizes during evaporation in the air, and the foda attracting carbonic acid will he rendered a carbonate of foda. It has a peculiar fmell, and acrid tafte, and changes violets green. When frefh, it is quite infolubie in water, but afterwards com- bines eafily with it. After its d-fcharge it becomes more opaque and confifteiit, but in a few hours it becomes even more clear and fluid than before, and in a few days depofits rhomboidal and foliated cryftals of phofphate of lime. XXV. Sweat. Its fmell and tafte varies much in dif- ferent fubjefts ; in general, it changes blue vegetable juices red i this property is faid to be chiefly poffeffed by the fweat of gouty perfons, and to be occafioned by the prefence of phofphoric acid. XXV*. Liquor of the amnios. This by the analyfis of Buniva and Vauquelin appears to differ confiderably in women and in cows. In the former albuminous matter, foda, muriate of foda, and phofphate of lime, is contained in the proportion of 0,012 only, in water. It depofits on the body of the foetus a cheefe-like matter, which is not afted on by oils, or by alcohol ; appearing to be a mixture ©f animal mucibge and fat, formed, in their opinion, by a degeneration of the albuminous matter which affumes the 183 character of fat, in the fame manner as happens to fcetufTes detained in the uterus beyond the natural period. This liquor in cows differs from that of women in its tafte, co- lour, fpecific gravity, and greater degree of vifcofity. It contains a peculiar animal matter, foluble in water, and in- folubie in alcohol ; not convertible into jelly like animal mucilage, nor combining with tannin, ammoniac, pruffic acid, and empyreumatic oil, like the vegetable mucilage. They alfo afcertained that it contained an acid of a particu-- lar nature, which they term the amniotic acid. Un- like the faccholadic it yields ammoniac by diftiilation, and unlike the uric it is foluble in boiling alcohol, and cryftal- lizes in long, whitej. and fhining needles.—Ann. de Chim. No. 99. XXVII. The zoo mc actd is a new acid difcovered by Berthollet. The fluid obtained by diftiilation from animal fubftances, has been hitherto thought to contain no olfur principle than carbonate of ammoniac and an oil. Bertho!1- kt has afcerta'ned that it contains an acid, which he names zoonic acid. He has obtained it from bones, woollen rags, Sec. alfo from the gluten of wheat, and the yeaft of beer. To obtain it, after feparating the oil from the liquor yielded by the deftruftive diftiilation, he adds lime to this liquor, then feparates the carbonate of ammoniac by a boiling heat, and adds more lime; thus obtaining the zoonate of LIME. By diddling a mixture of phofphoric acid with the zoonate of lime, he obtains the pure zoonic acid. The zoonic acid fmells like meat which has been roafted ; a procefs, in which indeed it is formed. It is of an auftere tafte, reddens turnfole, and effervefces with alkaline car- bonates. It has a ftronger attraftion to the oxides of mer- cury and lead, refpeftively, than the acetous and nitric acids. The zoonate of pot-ash calcined does not form a pruffiate of iron, with a folution of that metal. Ann. de Chim. xxvi. Tromfdorff thinks this acid of Berthollet, which he ima- gined to partake of both an animal and vegetable nature, is- analogous to the febacic acid. XXVIII. The formic acid, or the acid of ants, exifts in fo difengaged a date, that the tranfpiration of thefe ani- mals, and their fimple contaft proves its exidence. The large red ant furniflies the greated quantity, and feems to be mod replete with it in the months of June and July, when its merely pafling over blue paper, is fufficient to turn it red. This acid may be obtained by fimple diflillation, only mixed with a fmall quantity of empyreumatic oil, from 184 which it may be feparated by a funnel. Its fpecific gravity being to that of water, as 1,0075 to 1,0000 ; when exceed- ingly pure, it is as 1,0453 to 1. It may alfo be obtained by lixivatio'n, wafhing the ants firft in cold, and then in boiling water, until all the acid is procured. It may like- wife be obtained in a formiate of pot-ash, or of soda, by placing linen cloths impregnated with an alkali in an ant-hill. It affefts the nofe and eyes in a peculiar, but not difagreeable manner. When pure, its tafte is burning and penetrating ; but agreeable, when diluted with water. It poffeffes all the characters of ac ds. When boihd with fulphuric acid the mixture blackens, white penetrating va- pours arife, and a gas is difengaged, which unites difficult- ly with diftilled water, or lime water; the formic acid is hereby decompofed, for it is obtained in lefs quantity. The nitric acid diftilled from it deftroys it completely ; a gas rifing which renders lime-water turbid, and is difficultly :»od fparingly foluble in water. The muriatic only mixes with it, but the oxy-muriatic acid decompofes it. It unites perfectly with fpirit of wine, but difficultly, even with heat, with the fixed or volatile oils. The 1 rder of its af- finities feems to be barytes, pot-afh, foda, lime, magnefia, amnion! ic, zinc, manganefe, iron, lead, tin, cobalt, cop- per, nickel, bifmuth, fiher, alumine, effential oils, water. (Ardvidfon and Oeihn). An acid may likewife be obtain- ed from the millepedes. (Lifier). From the find rejected by the great forked tail caterpillar of the willow (Ben- net.) From grafshoppers, the may-bug, the lampyris, and filkvoorm. The acid is extrafted ly digefting the fubjeft of experiment in alcohol, which diffolves the acid, and precipi- tates the foreign animal matters. XXIX. The eggs of birds confift of an offeous cover- ing called the fhell, a membrane, the albumen or the white, and the yolk. The /hell, like bones, contains a gelatinous principle, with the carbonate and the phofphate of lime. The white is of the fame nature as the ferum of blood: heat coagulates it, fo do acids and alcohol. By diftiilation it affords a phlegm, which eafily putrifies, then carbonate of ammpniac and empyreumatic oil came over, a coal remain- ing in the retort which yields foda and phofphate of lime. Sulphur has. alfo been faid to have been obtained from it by fubl;mation (Deyeur.) The yolk' of eggs alfo contains a lymphatic fubftance, mixed with a certain quantity of mild oil which, on account of this mixture^ is foluble inwa- ter. 185 i ¥'c hair, wool, and bristles of animals dif- fer both from the bones and white animal foft parts, con- taining lefs jelly, fat, and lymph. XXXI. Feathers appear to differ chiefly, chemically confidered, from the foregoing fubftances in containing a ftill fmaller proportion of fat and jelly. The quills, how- ever, approach more to the nature of horn. XXXII. Silk, and the web of other caterpillars, much refemble wool in their chemical properties. Welter treated filk with the nitric acidr to obtain oxalic acid : when ob- tained he returned it with fome water and the contents of the receiver into the retort, and by feveral diftillations pro- cured afilkyfalt of a golden yellow colour, which afted as gunpowder on the contact of an ignited body. Its cryftals are oftahedrous and of a bitter tafte. He alfo found, in ani- mal fubftances, another peculiar kind of matter, colourlefs, foluble in concentrated nitric acid and precipitable by water. Phil. Journal, Sept. 1799. XXXIII. Concretions, fuch as are found in the pi- neal gland, are in general boney, with an excefs of phofphate of lime. Inteftinal calculi are, generally, in man, oily concretions, formed of the fat waxy matter of the bile ; in brutes, they are commonly formed of ammoniaco-magnefian phofphate, and fometimes of the phofphate of lime. XXXIV. Cantharidfs are infefts which applied, in fine powder, to the epidermis, caufe blillers and excite heat in the urine, with ftrangury. They produce the fame- ef- fect s on the urinary paffage, taken internally in fmall do- fes. Water extracts from them a reddifh bitter extraft, and a yellowifh oily matter; and either takes up a green, very acrid oil, in which the virtues of the cantharides moft eminently refide. To form a tincture, which unites all the properties of the cantharides, equal parts of alcohol and water muft be employed r if fpirit of wine alone be ufed, it takes up only the cauftic part. XXXV. Millepedes, afelli, porcelli, woodlice. Thefe yield, by diftiilation, an infipid or alkaline phlegm, the refidue affording an extraftive mattery an oily waxy fub- ftance, foluble in fpirit of wine only, and a muriate, with an earthy and an alkaline bafe. XXXVI. Cochineal. Thefe infefts are more efpecially ufed in dying; their colour takes readily, upon wool: the moft fuitable mordant is the muriate of tin. Florence lake,, is formed by precipitation by fixed alkalies, of the colour- 186 ing matter, and of alumine from a decoction of cochineal in fulphate of alumine. XXXVII. Ambergris, is a light afh-coloured body,. chiefly tound on the fea-fhores in the Eaft-Indies. It yields a grateful fmell, foftens with heat, and affords, by diftiila- tion, an acid and an oil, very fimilar to that of am- ber. Ambergris has been found in the inteftines of a whale, and has been alfo expelled by the fundament. It is found moft commonly in fickly fifh, and is fuppofed to be the caufe or effect of difeafe.*----Phil. Tranf. 1791. XXXVIII. Lac, or gum lac, is a kind of wax col- lected by red-winged ants from flowers in the Eaft In- dies, which they tranfport to the fmall branches of the tree where they make their nefts, The Hindoos have fix names for lac; but they generally call it Lacfha, from the multitude of fmall infects, which, as they believe, dif- charge it from their ftomachs on the tree, on which they form their colonies. The Lacfha, or Lac infeft, is a genus in the clafs of Hemiptera. The chermes lacca is always found on the branches of the mimofa glauca, or mimofa ci- nera, or on a new fpecies called by the Gentoos conda corin- da_____Dr. W. Roxburgh, PbiL Tranf. 1790. OF ANIMAL PUTREFACTION. Every animal body, when deprived of life, fuffers a gradual decompofition or refolution, which is effefted chiefly by the aeeefs of air, aided by a due degree of moifture and of heat. Its colour firft becomes pale ; its confiftence di- miniflies, its texture is relaxed, and, a faint and difagreeable fmell is emitted. The colour at this time changes to blue and green, the parts become more and more foftened, the fmell becomes; fetid, and the colour of an obfenre brown. The fibres now yield, the texture is more refolved, the pu- trid and naufeeus fmell is mixed with a fmell of a more penetrating kind, arifing .from the difengagement of am- moniacal gas; after this the mafs becomes of ftill lefs and defiv confiftence, the fmell more faint and naufeous, and the effluvia exceedingly active and injurious, arifing, it has been faid, frbnvthe feparation of phofphorated and carbonated hy- dro 'en gas ; a feparation of phofphoric light taking place at the "fame time. When it has continued in this ftate fome time, the mafs again fwells up, and carbonic acid gas is feparated • this part of the procefs is protrafted for fome time, when it chanees into a foft putrid mafs. 187 A great part of the hydrogen, and the remaining carbon, with the other fixed radicals, now gradually form a dark, brown, foft, earthy matter. This refult forms foil, which, mixed with mould, the remains of vegetable putrefaftion, forms the common receptacle for the roots, and germinating feeds of vegetables. When this refolution takes place at the fame time with vegetable matter, as in marfhes, fome portion of the hy- drogen and phofphorus produce the ignes fatui, and fuch luminous appearances. If this refolution is accompli flied in a confined place a foul mufty fmell is difcoverable. Heat, moifture, and the accefs of air fhould be avoided if it be intended to prevent this procefs from taking place. In one or other of thefe modes the various antifeptic proceffes aft, fuch as covering with refins and balfams, drying, fak- ing, and fmoking, immerfion in fpirits, freezing water, &c. TABLE OF PRECIPITATIONS, APPARENTLY BY SINGLE ELECTIVE ATTRACTIONS, FROM BERGMAN; WITH ALTERATIONS AND ADDITIONS, By GEORGE PEARSON, M. D. F. R. S. Caloric. In Water. Oxygen ./Ether Alcohol Ammonia Water Vol. Oils Glafs Q-, Silver Bafes of all Gafes. OxVGIK. In Water. Bafis of Mu- riatic, and various other Acids. Carbon Phofphorus Sulphur Light. Zinc Copper Lead Iron Silver Platina Q^ Silver Gold. Nitrous Gas P4uria. Acid Nitrous A. Sulphuric A Manganefe Ox-white Hydrogen Vol. Oils Alcohol Water /■; Fire. Carbon Zinc Iron Hydrogen Metal-Mang Cobalt Nickel Lead Tin Phofphorus Copper Bifmuth Antimony Q^ Silver at 6oo° Arfenic Sugar Sulphur Caloric Gold Silver Platina Q^ Silver, at above iooo0 Manganefe Ox-white Sulphur. In Water. Oxygen Molybd. Ox. and Acid Ox. of Lead ----Tin ----Silver ----O^Silv. ----Arfenic —— Antim. Iron Fixed Alkal. Barytes Strontia Lime Magnefia Phofphorus Fat Oil Vol. Alkali. ^ther Hydrog. G. i In Fire. Fixed Alkal. Oxygen Iron Copper Tin Lead Silver Cobalt ? Nickel ? Bifmuth Antimony Q;, Silver Arfenic Uranite ? Molybdena Sylvanite Sal. Sul- phurits. In Water. Oxvgen Ox. of Gold Silver Q^Silv. Arfenic Antimony Bifmuth Copper Tin Lead Ox. of Nikel Cobalt Mangan. Iron Other Oxides Carbon Water Alcohol zither.' In Fire. Manganefe Iron Copper Tin Lead Silver Gold? Antimony Cobalt Nickel Bifmuth Q^ Silver c Arfenic ? Carbon Silica. In Water. f luor A. Fixed Alkali Barytes ? Strontia ? AtUMINK In Water. Sulphuric Nitric Muriatic Fluoric Arfenic Oxalic Suberic Tartarous Phofphoric Acetous and:' other Acids* 190 Alkalies Barytes ? Strontia ? In Fir Pruffic AcidslFat Oil Fix. Alkali? Sulphur Lime ? Water Phofphoric Boracic Arfenic Sulphuric Nitric Muriatic Fluoric Sebauc Succinic Formic Lactic Benzoic Aceto. Acids p Fixed Alkali' Sulphur Ox. of Lead Fat Oil Sulphur In Fire. Phofphoric Boracic Arfenic Sulphuric Succinic Fluoric Nitric Muriadc Sebacic ormic Lactic Benzoic Aceto. Acids Barytes. In Water. Sulphuric Oxalic Fixed Alkali Sulphur Ox. of Lead Succinic Fluoric Phofphoric Lacteo-Sac. Molybdic Mi trie Muriatic Suberic Sebacic Citric Tartarous Arfenic Aci Strontia In Water. Sulphuric Oxalic Tartarous In Fire. Not afcertai. 9- LrME. In Water. Oxalic Sulphuric Tarta Fluor Succinic Phofphoric Lacteo-fach, Nitric Muriatic Suberic Sebacic Fluoric Arfenic Formic Lactic Citric Benzoic Acetous Boracic Sulphureous Nitrous Carbonic Pruffic Acid Suberic Sebacic Formic Lactic Benzoic Aceto. Acids Fixed Alkal Sulphur Ox. of Lead (Formic Lactic Benzoic Aceto. Acids Fixed Alkali Sulphur Ox. of Lead 10. Magnesia In Water, Barytes r Water Oxalic Formic Laftic Benzoic Acetous Boracic Phofphoric Acetous Arfenic Boracic Fat Oil Sulphur Phofoh^wis Phofphoric Sulphuric Fluoric Sebacic Arfenic Lacteo-fac- charine Succinic Nitrous Muriatic Suberic Tartaric Citric ? Formic Lactic Benzoic Acetous Boracic Sulphureous Carbonic ruffic Acids Sulphur n. 12. 13* Veg. Fos. AND Vo-L- Alkalies. In Water. Sulphuric Nitric Sebacic Muriatic Suberic Flu Phofphoric Oxalic Tartaric Arfenic Succinic Citric Formic Lactic Benzoic Acetous and Lacteo-fac- char. Acidi Boracic Sulphurous Nitro. Acid* In Fire. In Fire. Carbonic A. Pruffic A. Water Carbonic Other Acids? Sulphureous F.lk. Nitrous Carbonic Water Phofphoric Boracic Arfenic Sulphuric Succinic Fluoric Nitric Muriatic Phofphoric Boracic Arfenic Sulphuric Succinic Fluoric Nitric Muriatic Sebacic Fat Oil Sulphur Met. Oxides In Fire. Phofphoric Boracic Arfenic Sulphuric 191 Succinic Fluoric Nitric Muriatic Sebacic Formic Lactic Benzoic Aceto. Acids Barytes Lime Magnefia Alumine Silica Sulphur „ J5 sulphuric Acid. In Water. Magnefia Ammonia Alumine Barytes Jargonia Strontia Pot-Aih Met. Oxide Water Alcohol Sod j Lime Magnefia Ammonia Jargonia i 14. Water- Pot-Afh Soda Ammonia Alcohol Carbonate of Ammonia Alumine Metallic Ox- ides, 20 fpecies ►Order in which pre- cipitated 17. 18. 19. 20. 21. Nitrous, Nitric, Muriatic, Oxy-muri- atic, Ni- tro-M-uri- ATIC Acids. In Water. Water Alcohol jEthe Sulphuric A Sulphate of Pot-Afh Sulohate of Alumine Sulphate of Iron Oxy Muriate of'QaSilver Other com- In Fire. Pot-Afh Soda Baiytes Strontia Lime Magnefia Jargonia Met. Oxides Pot-Aih Soda 24. Fl uoric Acid. In Water. Li lme Barytes Strontia Magnefia Pot-Aih Sods Ammonia Alumine Met. Oxides Silica Water Alcohol In Fire. Barytes Strontia Lime Magnefia Ammoniac Alumine Lime Baryt Strontia Magnefia Pot-Afh Soda Met. Oxides Met. Oxides Water Alcohol Ammonia Alumine 16. Sulphure- poundsnot ous Acid, decompof by Sulphu ric Acid Silica Barytes In Water. Strontia Lime Pot-Aih Soda In Fire. Water Alcohol In Fir Lime Baryt Strontia Magnefia Pot-Afh Soda Met. Oxides Ammoniac Alumine 24. 25. OxALTC and Tar- tareovs Acids. In Water. Lime Barytes Strontia Magnefia Pot-Afh Soda Ammonia Ammonia Alumine Alumine 23. Boracic Acid. In Water. Met. Oxides Water Alcohol Barytes Strontia Pot-Aih Soda Magnefia Met. Oxides Lime Ammonia Soda Barytes Strontia Magnefia Pot-Aih 26. Citric Acid. In Water. Lime Barytes Strontia Alumine Ammonia jAlumine ■Met. Oxides Magnefia Pot-Aih Soda Ammonia 192 Alumine (Water Met. Oxides Akoho1 Water Alcohol 27. Benzoic Acid. In Water. In Fire. Barytes Strontia Lime Magnefia Pot-Afh Soda Met. Oxides 30. 31. 32. tWater Acetous, (Alcohol Lactic, andFoRMic Acids. In Water. Barytes Pot-Aih Soda W. Oxide o Arfenic Pot-aih Soda Ammonia Barytes Lime Magnefia Alumine Trcmfdorf ? Ammonia Strontia Alumine In Fire. Lime Barytes Strontia Magnefia Pot-Afh Soda Mxt. Oxides Ammonia Alumine 2S. Succinic Acid. Baiytes Lime Magnefia Pot-Aih Soda Ammonia Alumine Met. Oxides Lime 29. Lacteo Saccha- rin e acid In Water. Magnefia Lime Barytes Magnefia Met. Oxides Water Alcohol Pot-Afh Soda Ammonia Alumine Met. Oxides Water Alcohol In Fire. Lime Barytes Strontia Magnefia Pot-Afh Soda Met. Oxides Lime Barytes Strontia Magnefia Pot-Aih Soda Met. Oxides Ammonia Alumine Alum.ne In Fire. Barytes Strontia Pot-Afh Soda Lime Magnefia Met. Oxides Ammonia Alumine 33- 34- Sebacic AND phosphoric Acids. In Water. Lime Barytes Strontia Magnefia In Fire. Strontia Magnefia Pot-Afh Soda Ammonia Alumine Met. Oxide* Water Alcohol Ammonia 35- Prussic Acid. In Water. Aikalies Barytes Strontia Lime Henry In Fir Lime Barytes Strontia Magnefia Pot-Aih Soda Met. Oxides Ammonia Alumine 3*. Carbonic Acid. In Water. Barytes Strontia Lime Fix. Alkalies Magnefia Ammonia Alumine Met. Oxides Water Alcohol 3«. Chromic Acid. In Water. Fixed Aikali Ox. of Lead do. of Copper 39- Molybde- nic Acid. Sulphur Fix. Alkalies Abf. Earths Met. Oxidei 40. TUNGSTE- nic Acid. Met. Oxides'Barytei Lime Barytes Magnefia Alkalies Alumine Elluyarts 193 4*- Oxide of Arsenic In Water. Muria. Acid Oxalic Sulphuric Nitric Sebacic Tartaric Phofphoric Fluoric Lacteo-fac- charine Succinic Citric Formic Arfenic Lactic Acetcus Pruffic Acids Ammonia Fat Oil Water Sulphuric Nitro-Muri. Muriatic Nitric Phofphoric Acetous Gallic Pruffic Carbo. Acids Sulphur W^ter Arsenic In Fire. Nickel Cobalt Copper Iron Silver Tin Lead Gold Platina Zinc Antimony Sulphuret of Alkali Sulphur 42. Oxide of Titanite In Water. Sulphuric Nitrous and Muri. Acids Pruffic A. Oxy-Muria Nitro-Muri, Titanite In Fire. 43- Oxide of U R A N I T E . Nitrous Sulphuric Muriatic Sebacic Arfenic Acetous Other Acids Urakiti, In Fire. 44. Oxide of sylvan1te In Water. Nitrous Nitro-Mur Sulphu. Acid Sulphur Alkalies O^Silver Water Oxide of Manga- nese In Water. Acetous Arfenic Lactic Acids Arfenic Boracic Pruffic Carbonic Vol. Alkali Nickel. In Fire. Manga- nese. In Fire. Copper Iron Gold Silver Tin Sulphuret of Alkali Cobalt Arfenic Copper Gold Tin Antimony Platina Bifmuth Lead Silver Zinc Sulphuret of Alkali Sulphur 46. Oxide of Nickel. In Water. Oxalic Acid sylvanite In Fire. Q^Silv Sulphur Muriatic Sulphuric Tartarous Nitric Sebacic Phofphoric Fluoric Lacteo-fac- charine Succinic Citric Formic Iron 47- Oxide of Cobalt. In Water. Oxalic Acid Muriatic A. Sulphuric A, Tartarous Nitric Sebacic Phofphoric Fluoric La-fleo-fac- charine Succinic Citric Formic Lactic Acetous Arfenic Boracic Pruffic Carbonic Vol. Alka'i C O 11 A L T, In Fire. Iron Nickel Arfenic Copper Gold Platina Tin Antimony- Zinc Sulphuret of Alkali Sulphur Oxide of Bismuth. Oxalic A. Arfenic Tartaric Phofphori* Sulphuric Sebacic Muriatic Nitric Fluoric Lacteo-fac- charine Succinic Citric F ?rmic Acetous Prussic Carbonic Vol. Alkali Bismuth. In Fire. Lead Silver Gold 194 Q. "Silver Antimony Tin Copper Platina Nickel Iron Zinc Alkaline Sul jjhuret jSulphu Sulphur Zinc [Gold Platina _ Silver Arfenic [Cobalt Jkaline Sulphuret Bifmuth Lead Nickel llron Oxide of Iron. In Water. I Alkaline I ?3« Sulphuret | Oxide or Lead. ISulphur 1 I" Water. 52. Oxide of Tin. In 'Water Pyromuc. Sulphuric Sebacic Pyromuc. A Sebacic ZZ. (Sulphuric jPyromuc. Muriatic Sach. Laaic|Sebacic Gallic Camphoric lphuric Lacteo-fac- charine Muriatic Pyromuc. Nitric Sulphuric Pyromuc. Nitric Tartaric Lacteo-fac- charine Phofphoric -Citric Succinic Fluoric Arfenic Formic Lactic Acetous Boracic Pruffic Carbo. Acids Sulphur ltnc Sebacic Tartarous Phofphoric Citric Succinic Fluoric Arfenic Formic Lactic Phofphoric Arfenic iFlttoric Succinic Citric Formic Lactic Acetous Boracic Pruffic Carbo. Acids Lacteo-fac- charine Oxalic Arfenic Tartaric Phofphoric Muriatic Molybdic Suberic , Zoonic |Nitric Pyromuc Fluor Citric Formic Acetou* Lactic Boracic Pruffic Carbo. Acidi Tartarous Muriatic Sulphuric Oxalic Arfenic Phofphoric Nitric Succinic Fluoric Sachlactic Citric |Formic Lactic Acetous Boracic Pruffic AcidB '■ Fixed Alkali\ Vol. Alkali 'Fixed Alkali Fat Oil Tin. •=:__ In Fire. Lead" In Fire. Iron Copper Tin Lead Nickel Silver Bifmuth Zinc In Fire. Copper Antimony Tin Q^ Silver Silver Gold Cobalt Arfenic Platina ..... Cobalt Arfenic Manganefe Copper Gold Silver Tin Antimony Platina Bifmuth Lead Q^ Silver Zinc Q^Silver Antimony Copper Gold Silver Lead Iron Manganefe Nickel Arfenic Platina Bifmuth Cobalt Alkaline Sulphurets Sulphur Gold Silver Copper Q^ Silver Bifmuth Tin Antimony Platina Arfenic Zinc Nickel Iron Alkaline Sulphuret Sulphur 195 ^ 54* Oxide of Copper. In Water. Pyromuc. Oxalic Tartaric Muriatic Sulphuric Sach. Lactic Nitric Sebacic Arfenic Phofphoric Succinic Fluoric Citric Formic Acetous Lactic Boracic Pruffic Carbo. Acids Fixed Alkal Vol. Alkali Double Salts Eat Oil Copper. In Fire. Oxide of Q^Silver In Water. Sebac Muriatic Oxalic Succinic Phofphoric Arfenic Sulphuric Lacteo fac- harine Tai tar Citric Nitric Fluor Acetous Boracic Pruffic Carbo. Acids Nitric Arfenic Fluoric Tartaric Citric Formic Acetous Lactic Succinic Pruffic Carbo. Acids Vol. Alkali Q^SlL VER. In Fire. Gold Platina Lead Gold Silver Arfenic Iron Manganefe Zinc Antimony Platina Tin Lead Nickel Bifmuth Cobalt iTin Zinc Bifmuth Copper Antimony Arfenic Q^ Silver Alkaline Sulphuret Sulphur Iron Sulphuret of Alkali Sulphur 56. Oxide of Silver. In Water. Sebacic Oxalic Sulphuric Lacteo-fac- charine Phofphoric Silver. In Fire. Lead Copper Q^ Silver Bifmuth Tin Gold Antimony Iton Manganefe Zinc Arfenic Nickel Platina Sulphuret of Alkali 57- Oxide of Platina. In Water. /Ether Muriatic Muriatic Nitric Sulphuric Arfenic Fluor Tartaric Phofphoric Sebacic Oxalic Citric Formic Acetous Lactic Succi. Acids Platina. In Fire. Arfenic Gold Copper Tin Bifmuth Zinc Antimony Nickel Cobalt Manganefe Iron Lead Silver C^, Silver Sulphuret of Alkali S8. Oxide of Gold. In Water. /Ether Vol. Alkalies Gold. In Fire. Q± Silver. Copper Silver Lead- Bifmuth Tin Antimony Iron Platina Zinc Nickel Arfeni* Cobalt Manganefe Sulphuret of Alkali 59- Alcohol. Ws /Ether Volatile Oil* Vol. Alkali Fixed Alkali Sulphuret of Alkali Sulphur Muriates Phofohoric A Muriatic Nitro-Muri Nitric Sulphuric Arfenic Fluoric Tartaric Phofphoric Sebacic Pruffic Acids Fix. Alkalies 60. JF. T H E P. . Alcohol VolaiileOils Water Suiphur Phofphorus Caoutchouc 196 6i. Vola tile Oil. /Ether Alcohol Fixed Oil Fixed Alkali Sulphur Phofphorus 62. Fixed Oil Barytes Strontia Lime Met. Oxides! Sulphur Alumine IPhofphorus Volatile Oil I Fixed Alkali Vola. Alkali A judicious critique has lately appeared in a periodical publication on the foregoing table. The differences between Dr. Pearjon and the Reviewer, proceed partly from difcoveries made Rnce the publication of the table, partly from the affinities being affumed from the expe- riments of different chemifts, and partly from difference of judgment hi matters of opinion. Thofe alterations which fubfequent difcoveries fcem to have rendered neceffary, the liberty has been taken of intro- ducing in the table. The other, remarks are here fubjo'mcd, as an in- rerefting and ufeful adjuncl to the table. remarks on Da. PEARSON'S TABLE of AFFINITIES. Column 1. Caloric—Why is ammonia put after alcohol ? Its •afeous ftate is permanent, at a much lower temperature than al- cohol vapour —Why does glafs precede mercury ? furely it does not boil fo foon. This column appears to us improper, and calculated to miiier.d. The only poffible method of juJgihg of the affinities of different bodies for caloric, is to afcertain the temperature at which they change their ftate, and to rank them inverfely at that temperature. According to that rule, alcohol ought to follow thg three gafes, oxygen, hydrogen, and azot. Column 2. Oxygen.—Iron decompofes water, even at the tempe- rature of the atmofphere, and ought therefore to precede hydrogen 5 but lead, and moft other metals do not, hydrogen is, therefore, by far too low in the fcale. Why is. fulphuric acid inferted ? No dif- tinction is made between metals and their firft oxides; yet their af- finities for oxygen are veiy different. Iron, for inftance, decompo- fes water, but the green oxide of iron does not. Column 15. Sulphuric acids.—The ord r in which they precipi- tate each other is not that of the affinities of metallic oxides for acids. This Prouft has fufficiently demonftrated. The reafon is. evident, every fuch precipitation is an inftance of the action of compound affinity. In columns 17, 18, 19, we would wifh to know, why barytes is placed below the alkalies. Columns 20, 21.—Oxymuriatic and nitromuriatic acids. The affi- nities of thefe acids, according to Lavoifier, are very different from what they are here reprefented to be. Column 22, 23.—According to Lavoifier, alumina ought to be placed after the metallic oxides. Column 26. Citric acid.—Lavoifier places alumina after the oxides. Column 28. Succinic acid.—Guyton places magnefia after the al- kalies. 197 Column 33. Sebacic acid.—Guyton places the affinities of this column as follows. Barytes, pot-afh, foda, lime, magnefia, am- monia, alumina, jargonia. Column 36. Carbonic acid—Dr. Hope places lime before ftrontian. Column 53. Oxide of lead.—The order of phofphoric and muri- atic acids affigned here, holds only above the temperature of 245°} below that temperature muriatic acid has the ftrongeft affinity.. Column 62. Fixed oils.—Berthollet has arranged the affinities of this column as follows. Lime, barytes, fixed alkalies-, magnefia, ammonia, oxides of mercury, other oxides, alumina. The Author of the article Chemiftry, in the Supplement to the Encyclopaedia Britannica, has added^the following table, which, however, is un- connected with the firft. Nitric acid, muriatic, fulphureous, ful- phuric, acetous, fulphur, phofphorus. A column might have been added for pyromucout acid, the affini- ties of bodies for which are, according to Guyton, as follows— Potafs, foda, barytes, lime, magnefia, ammonia, alumina, jar- gonia, oxides of metals. The affinities of pyrolignous acid are, according to the fame philofopher, as follows. Lime, barytes, potafs, foda, magnefia, ammonia, metallic oxides, alumina. A column, too, might have been added for jargonia. The affinities are vegetable acids, fulphuric acid, muriatic, nitric. TABLE Of the quantity of real & civ taken up by mere alkalizs and earths Mr. KIRWAN. 100 parts. Sulphuric. Nitrous. Muriatic. Carbonic Acid. Pot-afh 82,48 84,96 56,3 105, almuil Soda 127,68 135*71 73,41 66,8 Ammonia 383,8 247,82 171, Variable Baryt 5°» 56, 31,8 282, Strontia 72,41 85,56 46, 43>* Lime 143, 179,5 84,488 81,81 Magnefia 172,64 210, i">35 200, Fourcroy Alumine 150,9 335, nearly Bergman TABLE Of the quantity o/"alkalies and earths taken up by 100 parts of real Sulphuric, Nitrous, Muriatic, and Carbonic acids, faturated. Mr. KIRWAN. 100 parts Pot-afh. Soda. 78,32 73,43 136,2 149,6 Ammonia. Baryt. Stront. Lime. Mag. Sulphuric Nitrous Muriatic Carbonic 121,48 "7,7 177,6 95,i 26,05 4°,35 58,48 200, 178,12 314,46 354,5 138, 116,86 216,21 231,+ 7°, 55,7 n8,3 122, 57,92 47,64 898, 5°, Vide p. 15. R 2 APPENDIX. vN ^ J ! ^ K ■a: REFERENCES TO Dr. WOODHOUSE's ECONOMICAL APPARATUS. Fig. i. A is a ftand, made of tin, eleven inches high, confiding of a flat bottom, from which proceed* three upright pieces, of the fame metal, one inch broad, which are foldered to the top, in which there is a round aperture, three inches in diameter, to receive the bottom of a retort, or oil flafk. B is a hydroftatic lamp, with Argand's apparatus. C a retort, luted to a leceiver D, which is fupported by a frame of wood E. Fig. 2.< A is a cylindrical veffel of tin, eleven inches high, and twenty-one in circumference, open at a, fo as to admit the hydroftatic lamp, with a round aperture in the top, three inches in diameter, and feveral fmall holes ooo furrounding it. B is a circular cafe, fix inches high, formed of two pieces of the fame metal, which include alining of charcoal, in fine powder, one inch thick, at the top and on the fides. The lower part has an open- ing five inches in diameter, and in the middle of the upper part, there is an aperture, to receive the neck of an oil flafk. C is a flafk, from which proceeds the tube D, which enters the bottle E. In ufing this apparatus, the flafk, containing the fubjedl of the operation, muft be placed on the cylindri- cal body A. The cafe B, is then to be put over the flafk, and the tube D, which enters a perforated cork, joined to it with a ftrip of paper, covered with a paftc, made of flour and water. 202 The charcoal, with which the cafe B is lined, is a bad conductor of heat, hence, it is accumulated round the flafk, and thus prevented from flying oft", into the air. Fig. 3. A is a feparate fecYion of the cafe lined with coal, and the oil flafk, on the neck of which, the head of an alem- bic B, made of tin or copper, four and a half inches high, is placed. C the netk*of this veffel, nine inches long, enters an oil flafk D. To ufe this apparatus, the flafk muft be put on the top of the cylindrical body A fig. 2. The vefTel lined with coal, is then to be placed over the flafk, and the head of the alembic fixed to its neck. E the part ever the top of the head of the alembic, may be filled with cold water. This economical apparatus may be ufed j Firft. In obtaining the gafes from certain fubftances, which require the application of heat; as oxigenous air, from manganefe or red lead and the fulphuric acid ; or ammoniacal gas, from lime and fal ammoniac; or oxigenated muriatic gas from manganefe and the ma- rine acid, Sec. Secondly. In making ammoniac, and the liquid and concrete carbonate of ammoniac;, in uniting fulphur with pot afh, foda and lime ; to compofe fulphur of pot-afh, foda and lime; to form fulminating mercury, and the prufliates of lime, pot-afh, &c. Thirdly. In procuring feveral of the acids, as the ni- tric, muriatic, ox-muriatic, oxalic, fluoric, acetic, &c. Fourthly. In diftilling water, fpirits, and alcohol, &c. and uniting the fulphuric acid and alcohol, to form ether, &c. Fifthly. In the drying of powders, and in evaporating water, and fome of the acids, from faline folutions. A tin, copper, glafs, or queens-ware faucer, may be placed on the top of theftands, Fig. 1 or 2, for this purpofe. Sixthly. In making experiments upon all kinds of dyeing drugs, and Seventhly. In analyfing earths and the ores of metals,. in the humid way. ti(J5 This apparatus is preferable to that of Guyton, in many refpecls. Firft. It is lefs expenfive. The lamp of Guyton, is one of the worft of the kind, for a Chemical Laboratory. There is no occafion for a number of fcrews, to elevate or deprefs the retort or lamp, for a great or low heat may be made, merely by railing or lowering the wick. Secondly. It would be no very eafy matter, to place an oil flafk on the ring of Guyton's apparatus, fo as to conneft a long tube with it, to obtain oxigenated muri- atic acid gas, ammoniacal gas, Sec. And in the winter feafon, the cold air, a&ing on the belly of the veffel placed there, would deprive it of a portion of heat, and if the ore of a metal was boiled with an acid, in an oil flafk, it would keep jumping from the ring. When the cafe lined with coal is placed over a flafk, the heat is accumulated round it, and the veffel is kept fteady in one pofition. Retorts are alfo procured with difficulty, at this time, even in the great cities of the United States. It is of great confequence then to pro- cure a fubftitute for them. The head of the copper or tin alembic, fig. 3, fixed on an oil flafk, and its neck communicating with another, form a diftilling appara- tus, which may be ufed, in a great many chemical operations. Thefe obfervations are the refult of experience. For the method of procuring the gafes, acids, &c. vide, the common elementary treatifes on Chemiftry. An Account of the principal Objections to the Antiphlogistic System of Chemis- try: By James Woodhouse, M. D. Professor of Chemistry in the Universi- ty of Pennsylvania, &c* IN the year 1796, the celebrated 'Dr. Joseph Priestley published a pamphlet, entitled, Con- siderations on the Doctrine of Phlogiston, and the Decomposition of Water, in which he brought forward various objections to the Antiphlogistic System of Chemistry, which was at that time, al- most universally adopted. Monsieur Adet, then Minister Plenipotentiary from the Republic of France, to the United States, and Dr. John Maclean, Professor of Mathema- tics and Natural Philosophy, in Princeton College, New Jersey, wrote Answers to this work. These Gentlemen respectively proved themselves, to be accurately acquainted with the reigning opinions of the times; and the latter displayed great acute- ness of remark in his performance. Professor Mitchill, of New York, made an ingenious attempt, to reconcile the contending par- ties.* * Medical Repository, vol. i. p. 54. first edition. 206 I also had the honor of replying to Dr. Priest- ley, in an Experimental Essay, printed in the fourth volume,' of the American Philosophical Transactions, and in Three Letters, published in that truly valuable work, the Medical Repository, of New York. ^ After these various publications, the Doctor, ha- ving seen no reason to abandon any of his opinions, wrote another Pamphlet, which "he called, The Doctrine of Phlogiston established, and that of the Composition of Water refuted. Having been for several years, considering this subject, I have been obliged to give up certain parts of the new theory, and it is my intention to relate some striking objections to it, to which no satis- factory answer, has as yet, been made. SECTION I. Of the Airs produced, by transmitting the steam • of water over charcoal, exposed to a red heat. If pure charcoal, broken into moderately small parts, is exposed to a red heat, in a copper, glass, or earthen tube, and the steam of water is passed over it, carbonated hydrogenous, and carbonic acid gas will be obtained. Lavoisier particularly mentions this experi- ment, and considers it as one of die principal proofs of the decomposition of water, which is supposed to be formed, of eighty-iive parts, by weight, of 207 oxygen, and fifteen of hydrogen.f It is said, thac the oxygen of the water unites to part of the coal, and makes the carbonic acid, while its hydrogen escapes, dissolves another part of the coal, and give* rise to the carbonated hydrogen gas. Dr. Priestley has objected to this explanation, and has clearly proved, that if the coal receive but a small portion of water at a time, inflammable air, without any mixture of fixed air, will be produced. The Doctor calls to his assistance, the aid of Mr. Watt, who says, " it has been observed by Dr. " Priestley, and confirmed by my experience, " that when much water passes in the form of " steam, over hot coal, there is much fixed air •'formed; but little or none, when the water is " admitted so sparingly, that no steam reaches the " refrigeratory." The Doctor supposes, that the reason why more fixed air is produced when the supply of water is co- pious,is because more water is necessary to the con- stitution of fixed air, than to that of inflammable air. In order to acquire accurate information, con- cerning the proportion of the inflammable and fixed air in this process, the steam of water was trans- mitted by means of an Eolipile over one ounce of red hot coal, in a copper tube. Portions of the gases having been examined, for the space of two hours, by throwing a measure of the airs up over lime-water, in an eudiometer, it was found, that the fixed air was generally thirty in every hundred parts, of the airs obtained. f Lavoisier's Elements of Chemistry, p. 135* 20$ Four ounces of charcoal, taken promiscuously from a heap, were then exposed to a red heat, in an earthen retort, when six hundred and twenty-two ounce measures of inflammable and fixed air were generated. The ist zd 3d 4th 5th 6th 7th io ox. measures, was the atmospheric air of the veffel. 4 contained 30 4 . ..........20 4...........*$ 360 ........... 10 70........... 2 170...........o 622 The same coal, taken from the retort, wetted with water, and committed to it again, gave eighty one ounce measures of inflammable and fixed air. The ist 10 oz. measures, was the air of the vessel. 2d 12...... .contained 30' 3d 4°............25 4th 6............20 5'h 13............ ° 81 The same coal, wetted a third time with water* yielded one hundred and eighty-one ounce measures. of inflammable and fixed air. The ist 10 oz. measures, the air of the vessel. 2d 4.......contained 30" 3d 44.......... 4th 37.......... 5th 62.......... 6th 12.......... 7th 4.......... 8th 4.......... 30' 70 26 2? tr> 74 75 20 r °< 80 8 1 -1 92 99 o. 100, ^ 3 1S1 209 According to these experiments, Lavoisier must have possessed very inaccurate information, concern- ing the gases produced by exposing moistened char- coal to heat, and the inference of Dr. Priestley is just. As water is composed of eighty-five parts of oxy- gen and fifteen of hydrogen, the eighty-five parts of the former, ought constantly to unite with the coal, and form fixed air, and the proportions of the inflammable and fixed air should invariably be the same; or where two parts in bulk of the inflamma- ble air are found, there should be one part of oxy- gen, united to the coal, in the form of fixed air; but this is not the case, for when the airs are made from coal, the first portions are generally seventy inflammable, and thirty fixed; and the last are all inflammable, without any mixture of fixed air, pro- vided the heat is kept up, a sufficient length of time. SECTION II. Of the Gases obtained by exposing metallic Cal- ces and coal to a red heat. According to the new Theory of Chemistry, a metal is a simple body, and it is converted into a calx, by an union with oxygen, the base of vital air. Coal is also considered as a simple substance, and it is said, when it is added to a metallic calx, and S2 210 exposed to a sufficient degree of heat, that the me- tal will be revived, by the coal uniting with the oxygen of the calx, and thus producing fixed air. This theory is generally adopted, although it is not warranted by experiment, for upon exposing metallic calces and coal to heat, carbonic acid gas is not produced, but carbonated inflammable air, mixed with fixed air, the proportion of which di- minishes to the end of the process. Dr. Priestley exposed the scales of iron, which he calls finery cinder, previously made red hot, to a high degree of heat, with coal which contained no water. Carbonated inflammable and fixed air were generated, and the iron was revived. According to the Antiphlogistic theory, the agents in this process, were iron, oxygen and coal, and nothing but carbonic acid gas, should have been produced. Supposing that water had been concerned in this experiment, I made an attempt to exclude it from each of the substances, previous to their mixture, in the following manner. One ounce of the scales of iron, and the same quantity of charcoal were reduced to a very fine powder, and exposed separately, in covered cruci- bles, in an air furnace, well supplied with fuel, for five hours. They were then taken out of the fire, and mixed while red hot, in a red hot iron mortar, were triturated with a red hot iron pestle, formed of an iron ramrod, were poured upon a red hot sheet of iron, and instantly put into a red hot gun barrel, which was fixed in one of Lewis's black lead furnaces, and which communicated with the 211 worm of a refrigeratory, a part of an hydropneu- matic apparatus. Immediately after luting one end of the gun barrel to the worm, one hundred and forty-two ounce measures of carbonated inflamma- ble air, came over in torrents, every portion of which was mixed with carbonic acid gas. The. iron was revived. Here the effects of water were seen, as much as if it had been added to the coal, or had been trans- mitted over it, in the form of steam-. As the coal had ceased to yield air, before it was mixed with the finery cinder, and as no air can be obtained from this substance without water, a con- clusion was drawn, that this fluid existed in the scales of iron, and could not be driven off from them, by means of heat. An hypothesis was formed, that the finery cinder supplied the coal with water, which was decompo- sed ; its oxygen was supposed to unite with the coal and generate the fixed air, while its hydrogen esca- ped, dissolved part of the coal, and made the car- bonated inflammable air. This explanation appeared to be very plausible* but it has been overturned, by subsequent experi- ments, which are related in the first section. Inflammable and fixed air are also procured, by mixing coal, with the calces of zinc, iron, copper, lead, manganese, tin, and bismuth, as will be shewn by the following experiments. Half an ounce of the oxide of zinc, precipitated from a solution of white vitriol by caustic pot-ash, was washed in water, until it would not give a milky colour to muriated barytes, and was exposed 212 to a red heat half an hour, and then mixed with two drachms of coal, which had ceased to yield air, in an earthen retort, when it gave eighty-six ounce measures of carbonated inflammable and fixed air The ist 10 oz. measures, was the atmospheric air of the vessel. # 2d 4......contained 75 \ 25 3d 4...........4c J m 60 4*4...........15 IS 85 1 3 5* 4...........io>£ 90>3 6th 4........... 2 i z- 98 7th 56........... o J * 100 86 The same result happened, from using the flowers of zinc and coal, The metal in both experiments, was completely revived, and was found adhering to the neck of the retort, which was broken to obtain it. Very frequently, upon exposing the flowers of zinc and coal to heat, inflammable air, without any mixture of fixed air, will be obtained. Two drachms of the oxide of iron, made from a solution of green vitriol, by caustic pot-ash, and which had been half an hour exposed to a red heat, and one drachm of coal, gave two hundred and six- ty-nine ounce measures of inflammable and fixed air. The metal was revived. The ist 4 oz. measures, was the atmospheric air of the vessel. 2d 4......contained 65' 3d 4...........60 4* 4...........42 5* 4........... 30 y ^ 7° } 3 6th 5...........25 7th 200...........20 8th _44...........15. 269 .- 351 ) Et> 40 p n 5« > u 70 1 w ™ 75 ' 80 J *5S 213 Half an ounce of the oxide of copper, from blue vitriol by caustic pot-ash, which was exposed half an hour to a red heat, and one drachm of coal, yielded one hundred and six ounce measures of in- flammable and fixed air. The ist 4 oz. measures, was the air of the vessel. 2d 36 ..... . contained 100\ o\ g. 3d 10........... 741 » 26l g1 4th 10........... 20 T % 80! 3 cth 8........... i*f S* 88( g 6th 20........... io\ ?' 9°\ £ 7th 18........... $) 95 J • 106 Half an ounce of minium, and one drachm of coal, gave twenty-six ounce measures of inflamma- ble and fixed air. The ist 4 oz. measures was the air of the vessel. 2d 10......contained 1007 >? o 3d 8............45 4th \_............15 26 Half an ounce of white lead, and one drachm of coal, afforded fifty-three ounce measures of inflam- mable and fixed air. The ist 40Z. measures, was the air of the vessel. 2d 4 ..... • contained 8o\ zo\ -♦ 3d 18...........95/ £> 5/| 4th 4. .----,----8SU isl* 5th 9............ 7of*, 3<>f| 6th 8........... 2o\^ 8o\rf 7th _6........... "V 9V * 53 the vessel. 214 Half an ounce of the black oxide of manganese, and one drachm of coal, gave fifty-five ounce mea- sures of inflammable and fixed air. The ist 4 oz. measures was the atmospheric air of the vessel. 2d 4......contained 8o"\ 20") £• 3d 2°~...........95 / g 5 / ? 5* 10...........30 I S. ?0 I | 6th J...........25J* 75J? 55 Half an ounce of the white oxide of tin, and one drachm of coal gave seventy-four ounce measures of inflammable and fixed air. The ist 4 oz. measures was the air of the vessel. 2d 12......contained col a* 3d 10.......... 4th 26.......... 5th 22.......... 74 Half an ounce of the white oxide of bismuth, precipitated from a solution of bismuth, in the ni- tric acid by water, and one drachm of coal, gave thirty-eight ounce measures of inflammable and fix- ed air. The ist 4 oz. measures, was the air of the vessel. 2d 10......contained 30"! »> 70 T 3" 3d 9...........15 IS. 4th 10........... .8 5* 5........... 5 38 215 • All these calces, except bismuth and zinc, afford more fixed air than can be procured from coal and water, which is a proof, that they contain oxygen. Water appears to be a principal agent in producing part of the inflammable and fixed air, for these ga- ses are procured, in proportion to the quantity of this fluid, in the calces. If oxygen was the sole $ agent, no inflammable air could be obtained. The flowers or white oxide of zinc, frequently affording inflammable and no fixed air, when sub- jected to heat with coal, cannot be accounted for by the new doctrine. Mr. W. Cruikshank of Woolwich, Great Britain, having attentively perused the pamphlet of Dr. Priestley, was struck with the nature and quantity of the gases, procured from the scales of iron and charcoal. He repeated many of the ex- periments here detailed, and met with similar re- sults. He supposes that the oxygen of the metallic calces exists in the carbonated inflammable air, which he calls the gaseous oxide of carbon, and thinks it bears the same relation to carbonic acid gas, as nitrous air does to nitric acid. He thinks that none of the hydro-carbonates at present known, are similar in their properties to the gaseous oxides of carbon, being much lighter, and yielding a far less proportion of carbonic acid, when eombined with oxygen. § § Nicholson's O&omical Journal, for April 1801. £Dr. WoodAoude* ftecturcs on Cfjemifttg, Commence on the first Tuesday in November, of every Year, in the City of Philadelphia, and Old, on the last Day of February. HE possesses a complete Chemical Appa- ratus ; and during the Course, several thousand brilliant Experiments are exhibited. Specimens of the various Earths, Salts, Ores of Metals, &c. are shewn to the Class. i Uetbrr^ 9-70 wmm imm ■.ViUl^'C te'M m fi& I • • 1 isSS'tiifju;