':>^i»?*j '•'*%$&#■- •'• "V'v'tir'i-*^ ■■■•'.-^tfiaS^^. OBSERVATIONS ON THE NATURE AND CURE OF CALCULUS, SEA SCURVY, CONSUMPTION, CATARRH, AND FEVER: TOGETHER WITH CONJECTURES UPON SEVERAL OTHER SUBJECTS OF PHYSIOLOGY AND PATHOLOGY. \/ BY THOMAS BEDDOES, M. D. A NEW EDITION. _________________ /t+U-i\~ PHILADELPHIA: PUBLISHED BY JAMES WEBSTER. 1815. B3Tf« I? 15 * TO THE DISCOVERER OF THE VIRTUES OF VEGETABLE ALKALI, SUPERSATURATED WITH CARBONIC ACID, SIR, XT has been frequently with great con- fidence affirmed, that our acute pains are of fhort duration. A very flight ac- quaintance, however, with the tremendous catalogue of human maladies, will fatisfy us that this is the vain aphorifm of a fophifr, more anxious to place words in oppofition, than to obferve the courfe of nature. Our excruciating difeafes are, if I do not com- pute very much amifs, remarkable for length of paroxyfms, and for frequency of recur- rence; while in thofe of a different character, languor and depreffion are fcarce lefs intoler- able than the moil intenfe pain. a 2 I hope, > DEDICATION. I hope, and I believe, that this mighty mafs of evil will be gradually diminiihed, and finally difappear from the face of the earth. We are juit beginning to catch a glimpfe of the laws of animal nature; and now, when the human mind feems, in fo many countries, about to be roufed from that tor- por, by which it has been fo long benumb- ed, we may reafonably indulge the expec- tation of a rapid progrefs in this, the mofl beneficial of all the fciences. An infinitely fmall portion of genius has hitherto been exerted in attempts to diminifh the fum of our painful fenfations; and the force of fo- ciety has been exclufively at the difpofal of Defpots and Juntos, the great artificers of human evil. Should an entire change in thefe two refpedts, any where take place, every member of fociety might foon expect to experience, in his own perfon, the confe- quence of fo happy an innovation ; and mould the example be generally followed, there is no improvement in the condition of the World, for which we might not hope from the bioodlels rivaHhip of nations. From DEDICATION. v From Chemiftry, which is daily unfolding the profoundeft fecrets of nature, and, among the reft, the delicate play of living machinery, your example alone would juftify us in en- tertaining the moft fanguine expectations : fince the earlieft difcoveries in that de- partment of chemiftry, which has been fo fuccefsfully cultivated by Black, Caven- dish, Priestley, 6cheele, and Lavoi- sier, fuggefted to you a fafe and efficaci- ous remedy for one of the moft frequent, painful, and hopelefs of difeafes. Much as you have contributed, by the frank and difinterefted communication of vour difcovery, to obliterate one of the dark- eft fhades from the profpecT of life, your name is, 1 fufpect, fcarce known beyond the narrow circle of the praditioncrs of medicine, except, perhaps, to a few among thofe who are indebted to you for eafe and health. Such is the inattention of mankind to their beft benefa&ors ! and fo entirely have fatal illufions preverted our moral fenti- ments ! I cannot hope to add much to your reputation ; (1 DEDICATION. reputation; but by attempting to difTufe more widely the benefit for which mankind are originally indebted to you, I may per- haps afford you gratification. That the former part of the following pamphlet will do fome good, I am confi- dent ; though I do not believe that alkaline medicines will relieve calculous diforders under every form. Thofe diforders, befide the different feats they occupy in different perfons, appear alfo, from the analyfis of va- rious calculi, to be liable to confiderable variation in their nature. The fpeculations that follow, will, per- haps, appear to you too remote from appli- cation, and my hopes of the future improve- ment of medicine too high-flying. It is, I am fenfible, but a poor expedient, to lay one's felf out for the praife of inge- nuity by propofing projects which are in no danger of being difgraced by trial ; nor have I ever much regarded medical obfer- 4 vations, DEDICATION. vii vations, that are of no other ufe than to be read. But this, I can aflfure you fhall not be the cafe here; and the more I reflect, the more confident' I become, that an eafy and convenient method of offering phthifical patients a chance of recovery, which has never yet, upon any probable grounds been offered them, will fhortly be contrived. For typhus, if the light that is now dawn- ing upon phyfiology and pathology does not prefent objects to me under very illufive forms, we fhall not fail to ftrike out an al- moft infallible method of cure; and this method, 1 think it probable, will extend to the fcarlet fever alfo; which is perhaps the moft formidable among the acute difeafes of this climate. In the treament of fe- vers we have, it is true, learned to avoid fome fatal miftakes of our anceftors ; but we can boaft of little elfe. In thofe cafes in which alone there is, perhaps, occafion for the interference of art, art feems almoft im- potent : from attention to the fingle circum- fbnce of debility, I imagine, that patients are often drenched with wine and opiates, till they are ftimnlated to death. If I have imputed viif DEDICATION. imputed the debility to its real caufe, our chief aim fhould be to reftore the principle of excitability ; and ftimulants fhould in the mean time be adminiftered with a more fparing hand. Perhaps, when the proper method of reftoring this principle fhall have been devifed, extraordinary ftimulants will become unneceflary. The Materia Medica was once fuppofed to contain diftinct fpeci- fics for the difeafes of each feparate organ ; it is now regarded as little elfe than a collection of ftimuli; fothat medicine is become the art of adminiftering drams. Hence it can often only amufe or palliate, and muff fometimes injure, by forcing into motion, conftitutions already too much worn. How would our refources be multiplied, if we could give ex- citability or life, as well as ftimulants ! "But " is fo falutary a revolution in medicine ~S Introduced again under a new form, with ftg-- nalfuccefs - . - 5—y Single inconvenience of the new form - 8 Means of remedying it g Carbonic acid contributes to intoxication, note, New formula - - 10—11 Case I. 13—14 Stale beer fe ems to produce nephritic par ox - yfms - - - 15 Cyder, to prevent the generation of calcu* lus ibid. Case II. - - 15—T7 Case ill. - - 17—18 b Case IV. x C O N T E N T S. Case IV. - - - 18—20 Case V, 21—23 Eafy extemporaneous way tofupercarbonate alkali to a certain degree, note - 22 Other weak acids, either taken with alkali or not, equally calculated to prevent the bad effecJs of pure alkali - ibid. Case VI. Extreme irritability of the urinary paffages, independent of calculus, relieved by alkali - - 23—26 Letter of Mr. Jones, furgeon, in Newport, Shropjhire - - 27—34 Letter of Mr. Tonge, furgeon, in Shifnal, Shrop/hire. His experience of the good elfecls of foda pills, in cafes of biliary concretion - - 34—37 Series - - 37—39 Conjectures relative to fome other difeafes 41 D . Gritannerys Speculations borrowed part- ly from Brown, and partly perhaps from Mr, Hunter - - 43 Nature of fcurvy explained from the pneu- matic chemiftry - - 45 Various proofs, and remarks on Dr, Trotter 46—47 1. Want of oxygene in the folids - 48—49 2. Appear- CONTENTS. xl 2- Appearance about tht heart the fame as where the fupply of oxygene has been fud- denly cut off - - 50—32 3. I ejiciency of recent vegetable matter, net the exclujive caufe of f curvy - 52;—54 4. Fatls from Dr. Trotter, fee his work 54-58 5. Cafe of the Laplanders - 58—59 Oxygene loofely combined in raw frefh meat. Hence raw animal food cures the Jcurvy 59—60 6. Cafe offcurvy fom conformation in the blue boy of Dr. Sandifort 61—71 Similarity of his fymptoms to thofe of fcurvy, and thefe fy?nptoms unquef ion ably owing to too little oxygene being taken in by his lungs /.■ id. Diffcfiion—Aorta arifing partly and princi- pally from the right ventricle 71 — 76 Ehyfiological inferences - 77—78 Attempt to explain certain fenfations felt on very high mountains - 78—82 Propofal for a new foporifc, note - 80 7. Sorbutic fymptoms in M. de la Coniamine, after three weeks refidence in thefummit of PkhvicLt 82 b 2 rrrventiw Lit CONTENT S. Prevention and cure of fcurvy, deduced from the theo y - - -83 I. Air with its full proportion of oxygene ibid 2. Ufc of vegetable acids - 84 Difficulty—Why do not mineral acids cure Jcurvy P Have they, efpedaily the nitric, had a full trial? - - - 85 Nitric and fulphurh acids decompounded in the body - - 86 Query refpeBing herpes—Does it not a rife from a local want of oxygene f - 87 Black difeafe (fcorbutic leprofy) of the Cof- facks - 88—90 3. Sooins recommended—Cure effecled by them, even on /hip-board - 90—91 4. Nitre - - - 91, 5. Sweet wort no contemptible prefcrvative gi Relation between fcurvy and a fait diet 93 Concrete acid of tartar, a remedy well worth trial - - 94 Obfervations on the production of fat - 95 Chief difference between flejh and fat 95—98 fat formed in the living body by fubtraflion of a confitucnt part of flefld - 95-—98 Facts CONTENTS. xi« Facts Jihewing a tendency to form fat, where there is a deficiency of oxygene to a certain degree I. Dr Trotters negroes became regularly firfl fat, and then fcorbutic - 99 2. Acids produce emaciation - 100 3. Vegetables a cure for obefty, as well as for fcurvy - - lot 4. Perjons inhaling too little oxygene become fat - - 102 Objections - - 102—103 5. Exercife introduces oxygene - 104 Beautiful experiment of Mayow, note, ibid. Two periods of corpulence - 105 Hint refpetting longevity - 106 6. Much fleep produces corpulence - 107 Vegetable obefty - - 108—109 Of confumption.—Advantage of fpeculation in medicine - - 110—11 I No fin to fpeculate refpetting confumption ibid. Doubt refpetting the fcrophidous nature of confumption - - 1 I" pregnancy ffpeudi confumption ■ - 113 %ucry— xFv CONTEN T S. Query—Are pregnant women as much ox- ygenated as perfons in the ordinary fate of health - - 113—1*7 Phlhifical perfons hyper^oxygenaied Appearances, fuch as would take place, if the patienfs veffels were full of hyper-oxy- genated blood - - 117—124 Mr. Walker s obfervations on phthifcal blood 125 Similar obfervations of Mr, H—■----n ibid. Phihifisaggravated by oxygene air 126—127 -------• confderably relieved by air, deficient in 0 xvgene - - 128 Sailors much more expofed than others to the exciting caufes of confumption—are they proportion ablyfubjet~l to it ? 130 — I 3 £ Query—Connection between fcurvy and con- fumption? - - 132 Explanation of a. fact recorded by Dr, Lind Emaciation in phihi/is, whence? - 134 Effects of fulphurlc acid, how arc they pro- duced ? - - M(J Tzeeo hypothefes - - ibid, Experiments C O N T E N T S iv Experiments of Mr. Lavoifer and Dr. P rief ley - - 136—138 Inferences towards a cure of phthifs 1 39—141 Diet fhould conflft of meat overdone—of oils— medicines fhould be oily and alkaline ibid. Do mercurials produce phthifs, and why f 142—143 General confderation - - 144 Cafe of depreffion of the ribs in phthifs, 146 Importance of being able to modify the atmo- fpere - - 147—148 Frequency of confumption in Britain, owing to the variable nefs of our clirnate - 149 Confumption frequent alfo, according to Dr. Rufij, in Pennfyhania, where the climate is extremeley variable Theory of catarrh - 15S How to avoid catarrh - - ibid. Merits of Brown, note, - 159—161 Hoifelefs animals lefsfubjetl to catarrh, which is generally the effefi of artificial fiimmi 162—169 Girtanncr on the laws of irri I ability 171—21 o —----on the principle of irritability 2 11 Additional refections on pofitive a>;J negative flimuli - - 252 1 Caufe -u CONTENTS. Caufe and mechanifm of mufcular motion 258 Mode of action of the contagion of typhus 260—261 Intoxication produced by it - ib. note True indication of cure in that difeafe - 262 Typhus, and fome other difeafes, produced equal- ly by ordinary and extraordinary fiimuli 263 Method of curing thefeverifhnefs brought on by intoxication - - ibid, Profpett of the improvement of medicine 265 Neceffity of popular inflruflion in phyfiology and pathology in every well confiituted place of education - - 266 Conclufion - - 268 Addenda - - - 269 Paffage from the Flora Lapponica - ibid. Letter from Mr, Lefiie, on the treatment of confumption at Liege Academy 270—1 Conjecture on the ufe of manure - 272—8 a AN / ACCOUNT OF A SIMPLER METHOD of TREATING Certain Calculous Complaints, OOKS and tradition never fail to offer a multitude of medicines for difeafes that are frequent and incurable; many of thefe medicines are the fuggef- tion of the moft fantaflic analogies, and the greater part are incapable of even pal- liating for a moment the fufferings of the patient; yet a lift, at firft fight fo unpro- mifing, is not abfolutely without its ufe. The phyhcian ftalks about with an air of greater dignity when he feels a full quiver at his fhoulders, however blunt may be the arrows it contains; and it firpplies a ftafF, b however. ■z METHOD OF TREATING however feeble, on which the wearied fpin'o of the patient may reft, and defers a little that feafon of fettled gloom when Futurity has nothing to promife to Hope. There exifts, probably, no human ma- lady, not even the jaundice, confumption, ague, cancer, or dropfy excepted, for which fo many whimfical and nugatory means of relief have been propofed, as for the ftone and gravel. Befides an in- finity of inefficacious fimples, the whole feries of remedies, from the warm goat's blood of Alexander Trallianus, the pounded glafs of Baricellus a Sanclo Marco, § the effence of pigeon's dung of Johannes Poppius, the quint a effentia urina bumana of Fabri, thefpiritus microcofmi e fiercore hu- mano of another chemical or alchemical § Incredibile nee forte, unquam tentatum remedium, fays Dr. Siebold. Yet the powder occafionaily found within the cavity of ftones is ftill ufed as a remedy for calculous complaints in our chalk counties ; I met with an inftance of this kind within thefe few days. It was probably conceived, in both cafes, that one kind of grit would draw or drive the other out of the body. doctor, CALCULOUS COMPLAINTS. 3 doctor, down to the bearberry of De Haen, at once afford a proof of the ineflicacy of each particular medicine, and of the pre- valence of a diforder which could enforce fo much attention, and fuggeft fo many ex- travagant projects. ( From the teftimonies that have fallen under my obfervation, I can collect, that during the former part of the prefent cen- tury fome approaches had been making towards a remedy, which, whatever may be its mode of operation, or precife degree of efficacy, is undoubtedly capable both of relieving that pain, which renders the dif- order fo formidable, and of fufpending the progrefs of the difeafe itfelf. As early as the year 1721, Robinfon propofed fait of tartar, among other things, as a folvent for the ftone *. In diforders of the urinary organs, whether arifing from concretions or not, Hoffman praifes the efficacy of the hot alkaline fprings of Germany, as * Treatife of the Stone and Gravel, 1721. B 2 well 4 METHOD OF TREATING well as of the fait obtained from the waters of Carlfbad. At a later period, alkaline, fubftances enriched the Engl if h empirics, and obtained the commendation of Hart- ley, Whytt, Kirkpatrick, De Haen, and other phyiieians of great celebrity. It ap- peared, indeed, that the concretions were not really eiiffolved, even in the more fa- vourable cafes ; yet the pain was perma- nently relieved. Every phyfician is ac- quainted wTith the very curious facts on this fubject related by Whytt, and more efpecially by De Haen *. Yet, notwith- standing fome partial fucccfs, thefe cau- ftic materials were afterwards geaerally * See thee firft volumes of De Haen's Ratio Me- dendi. The cafe of that patient who had fwallowed eight hundred quarts of lime-water in half a year, and who continued free from pain for three years, though he had ftill a ftone in his bladder, is very remarkable. The ninth cafe, related in the " Account of the Effi- cacy," &c. affords • another fuch in ft an ce of palliation. The patient appears to have been kept more than tole- rably eafy by the fuperfaturated folution for two years and ah half: yet, from the concluding expreilion of his letter, " 1 am feldom troubled with any pain,'1'' I in- fer that the difeafe full cxifted in the bladder. laid CALCULOUS COMPLAINTS. 5 laid afide. They were, however, laid afide with regret, fince this inference feemed to be warranted by the whole fum of facts that much benefit might be derived from them, provided their collateral bad effects could be obviated. This conclufion appears evidently to have refted upon the mind of Profeflbr Bergman, who, as far as this diforder is concerned, may be quoted as an authority in medicine : in a paper publifhed in 1776 he has thefe words—" hoc umtm addo, calculi analyfin chemicam medico arti hand pa rum utilitatis polliceri, calcis viva aquam et lixivium caufHcum alkalinum calcuh mederi experientid confiilit. Idem verofi igno- tum haclenus fuiffet ex ipla calculi mixtions nunc inventa et detect a intelligeretur. It was referved for a refpectable mem- ber of the medical profeflion, ftill living, to engage the modern chemiftry in the fer- vice of medicine, and realize a project which now feemed to be reiinquifhed in defpair. This gentleman's reflections were quickened by his own feelings, and in 177S, METHOD OF TREATING 1778, after having been for eighteen years fubject to fevere nephritic paroxyfms, he began to take a folution of fixed vegetable alkali, fuperfaturated with carbonic acid, or fixed air. This medicine very foon re- lieved liis calculous fymptoms, and, as it appears from the account of his cafe, has kept him free fiom pain for ten years, one flight attack excepted, which is afcribed to the difcontinuance of the medicine for fe- veral weeks. Perhaps it might be fervice- able to mankind, if medical practitioners, attentive to the progrefs of fcience, and capable of combining ideas, were from time to time to be feized by thofe difeafes for which remedies are ftill wanting. The narrative of this cafe, with that of upwards of twenty others, is contained in a pam- phlet, now well known under the title of " An account of the Efficacy of Aqua Mephi- tica Alkalina, &c. in Calculous Difiordcrs." Experience has fince amply confirmed the virtues of a medicine, which, I apprehend, may be freely taken without danger, and even without inconvenience, except in a few rare CALCULOUS COMPLAINTS. 7 rare inftances, and which feems to have de- ferred the lingular praife of equalling the expectations raifed by the perfon who firft propofed it. The method of preparing this medicine is a follows: Diflblve two ounces and a half (troy weight) of dry, fait of tar- tar in five quarts (wine meafure) of foft water ; after ftirring the water, and then fuffering it to ftand long enough for the fub- ftances generally precipitated from water by fixed alkali, and the refiduum of the fait of tartar itfelf to fubfide, pour off the clear folution, and place it in the middle veffel of Parker's apparatus for impregnat- ing liquids with fixed air, and expofe it for forty-eight hours to a ftream of that elaftic fluid. Of the liquor, from twelve to twenty- four ounces have been taken every day by different perfons afflicted with various calcu- lous complaints, and always, except in one inffance, with the defired effect, after it has been continued fome time. One might perhaps, be difpofed to wifh that this remedy could be prepared with Ids 8 METHOD OF TREATING lefs trouble and attention ; but the great de- fideratum is a cheap, fafe, and efficacious formula, adapted to the poor, who are by no means exempted from calculous diforders ; for when the high price and brittknefs of the apparatus is confidered, and when we likewife take into the account the neceffity ofconflantly continuing the medicine, in order to prevent the return of the difeafe it will appear piobable, that the poor are not often likely to reap the full benefit of the difcovery. In the year 1786 or 1787, a perfon be- longing to the medical profelfion, and much afflicted with the gravel, complained to me that he was unable to perfevere in the ufe of aqua mephitica alkalina, on account of the great dizzinefs it always occasioned *. I was * LMzzinefs with a degree of intoxication, is a very common effecT: of liquors containing carbonic acid. Pyrmont water, which contains of carbonic acid air confiderably more than a quantity equal to the bulk of the water itfelf, occafionsa glow, exhilaration, and con- 2 fufion CALCULOUS COMPLAINTS. 9 I was led by this intimation to reflect upon the fubjeft, and after fome time fell upon what indeed was abundantly obvious; a for- mula of which I think myfelf fully war- ranted in afferting, that it is extremely be- neficial in calculous complaints, and that it may, without injury, be taken in very large quantities, and continued for a great length of time. Its fimplicity and its cheap- nefs are its great recommendations. I can- not determine, for want of comparative ob- fufion of ideas fimilar to that which follows the ufe or abufe of fpirituous liquors. This effect is fo com- mon as to have given rife to a particular term, brunnen raufch. A fpring of the fame quality, which the Tartars, on this account, call the well of drunkennefs, is men- tioned by one of the late travellers into Siberia. Some bottled liquors, I fuppofe, in part, owe their intoxicating power, and more efpecially the fuddennefs of their effect, to carbonic acid. This acid is produced in the bottles by a flow continuance of the vinous fermentation^ and therefore thefe liquors will contain more alcohol when phey are ripe, than at the time of bottling ; but I do not imagine this difference v/ill account fatisfactorily for the prodigious difference of their effecl: upon the head. Sparkling Champagne probably owes its exhilarating power to the fame caufe. c fervations, to METHOD OF TREATING fervations, whether it is inferior to the more operofe preparation in efficacy ; and how much inferior ; there can be no reafon to fuppofe that it is fuperior : and were both equally eafy to procure by all patients, I fhould not think it worthy of public no- tice. The formula I have employed for two or three years paft is as follows : take na- tron or fal fodse in cryftals, pound it coarfely, and expofe it to a warm dry air, till it en- tirely crumbles into a white powder ; make this powder into pills with foap or any other cement; aromatics, extract of bark, &c. may be added ; but I have never found any addition neceffary ; a quantity of foap, rather more than equal to the weight of the calcined alkali, is neceffary to make it into pills. * In * I now fee that Dr. Donald Monro (Materia Me- dica, article Alkali, 1788), had an idea of giving foffil alkali in pills, in calculous cafes," It may," fays he, and this is all he fays, " be made into pills or boluffes, " mixed CALCULOUS COMPLAINTS. In order to expedite the expulfion of the water of cryftallization, the alkali may be fpread out before a fire, or the veffel con- taining it may be placed in boiling water, and the pounded cryftals ftirred till they have loft rather more than half their weight: the recent cryftals contain indeed fixty-four parts of water in an hundred; but unlefs kept clofe, they lofe part of this water, and it is prudent not to carry the calcination too far, if artificial heat be applied ; nor fhould the heat exceed that of boiling wa- ter, left any of the volatile acid fhould be expelled; of this powTder, from one to two fcruples taken every day has generally af- " mixed with fome powder of liquorice root, by means " of gum arabic mucilage, or conferve." From fe- veral articles of that work I had., perhaps haftily, con- cluded that it fell fhort both of modern chemical, and medical knowledge, and this paffage had efcaped me. I fuppofe the author, as he gives no intimation of the contrary, means to propofe the cryftallized alkali for pills. I have often found the pills apt to fall to pieces, when the water of cryftallization is not fufficiently ex- pelled ; I fhould think this would happen ftill more, v/V:r. cone is expelled. C 2 forded It METHOD OF TREATING forded relief in lefs than three weeks ; and in no cafe but one, out of more than twenty that have fallen under my own obfervation, have they failed to perform every thing which could be defired from medicine, ex- cept eradicating the tendency to form cal- culous concretions, to which no known re- medy has the fmalleft pretenfions. I might perhaps fafely truft to the above- mentioned pamphlet, as bearing abundant teftimony to the efficacy of alkaline falts; and confidently appeal to .future experience in confirmation both of the power of fal fodse in the form prefcribed, and of its harmleffnefs; at all events it will be unne- ceffary to particularize flight cafes, which have always at once yielded to the remedy. The following, in which the fymptoms were either of very long ftanding, or extreme fe- verity, will, I hope, be fufficient to procure a trial to trie medicine. I. Mr, CALCULOUS COMPLAINTS. I. Mr. William Rushton, of the Wyke, near Shifnal, Shroplhire, had been ha- raffed for a confiderable number of years by excruciating pains in his loins, attended with occafional ficknefs, and an almoft to* tal inability to ftoop ; the pains were ac- cuftomed to fpread in all directions, and fe- verely to affect his head. He had at diffe- rent times difcharged much gravel ; his urine formed depofitions, was often ex- tremely offenfive, and full of mucus ; he was at times afraid to difcharge it, fo much were the paffages irritated, and fo intenfe the pain fuccceding the evacuation. In July, 1787, he began to take a drachm of chryftal- lized foflil alkali, diffolved in a quart of water, every day. In a few days he felt relieved, and in lefs than a month feemed, as he ex- preffed it, to be quite another man. I have feen him repeatedly fmce ; his fufferings from his complaints have been very inconfi- derable j but having fometimes neglected the 14 METHOD OF TREATING the medicine for months together, he has felt fome ftiffnefs rather than pain acrofs his loins, which has immediately been re- moved by a repetition of the alkali. The folution fometimes produced a flight naufea, againft which his dread of the pains determined him to bear up. The pills have never been attended with the flighteff. unpleafant fenfation. During his long ex- perience he obferved, that ftale (acid) beer never failed to bring on a fevere paroxyfm. Several other perfons have repeated the fame obfervation. On the prefumption arifing from this information, I have always enjoined abftinence from malt liquor in that ftate ; no other particular reftriction of diet has Appeared neceffary, yet the inhabitants of cyder countries, as I have been informed upon inquiry, are remarkably free from this difeafe. Do the native and acetous acids differ in their effects ? I fhould imagine not. The fpeedy effect of four beer feems to ihew that it does not act by producing new concretions, but by fome irritating power. CALCULOUS COMPLAINTS. 15 power. Would cyder affect a perfon fub- ject to calculous paroxyfms in the fame manner ? Diuretics, as diluted fpirits, ge- nerally do mifchief: the fame remark, I think, occurs in the pamphlet quoted above. May, 1792, Mr. R. gave me the ufual fa- vourable account of himfelf. II. Br am ah, a workman in the foundery of Mr. Dearman, of Birmingham, was become quite emaciated, and unequal to his labour, from a gravelly complaint, under which he had laboured many years. He had long been accuftomed to difcharge concreted matter, and fmall ftones ; his urine depofited anincruftation, and foon became foetid ; the pains at his loins were intenfe, &c. &c. He began to take the folution as before in October 1787, found relief in a few weeks, and foon confidered himfelf as radically cured. Notwithftanding my repeated ad- monitions, he has at times neglected to continue the medicine, and has had returns of i6 METHOD OF TREATING of his fymptoms. I never have feen an inftance which more evidently fhowed how foon we forget the moft acute pain. Having fo frequently experienced the efficacy of the medicine, he now choofes to fuffer the difeafe to return in a flight de- gree, and then for two or three days to take a handful of pills; the confequence of which is a difcharge of gravel, after which he feels no farther inconvenience for months. I have not been able to diffuade him from this violent method of treating himfelf ; he has not, however, fuffered from it. My friend, Mr. I. Dearman, in a letter dated May 2, 1789, gave me the following account of one of his relapfes, for he has fo often relapfed and recovered, that his cafe alone is equal to half a dozen, in proof of the power of the remedy : " He began " with half an ounce of fal fodae, with as " much common foap as with the addition " of a little gum arabic made fixty pills. " On fecond day (Monday) he took four, 1 " increafing CALCULOUS COMPLAINTS. 17 * increafing the number every day, till c yefterday he took twelve, wihout the ' leaft affection of the ftonlach or increafe 1 of urine; nor can he give any other ' account of their effect, than that the * pain is removing very faft, and he does ' not doubt but a few more pills will cure < him. I have not been without an appre- ' henfion of danger from his taking them fo ' largely—he treats my remonftrances very 4 cavalierly, and fays he fhould not mind 1 taking a box full of fuch pills. He does ' not recollect any increafe of urine when ' he was taking the medicine before.' Mr. Biddle, chemift, of Birmingham, in a letter dated June 1792, informs me, that ' Bramah ' and Wilks, at the foundery, have con- ' ftantly taken the pills, when they felt the 6 complaint coming, and have as uniformly ' been relieved.' III. Wilks, a fellow-workman with Bra- mah, and not quite fo terribly affliaed d with t8 ' METHOD OF TREATING with nephritic fymptoms, found perfect relief from the pills. After every other difagreeable feeling was removed, he con- tinued for fome time to have a ftarting of one of his thighs. Sufpecting this to arife from fome caufe of irritation lodged in the urinary palTages, or at leaft to have fome connection with his calculous difor- der, I advifed him to perfevere fteadily in the ufe of the pills ; and he has fince in- formed me, that he is no longer difturbed by this involuntary motion of his mufcles. lie alfo informed me, that he had cured two or three other perfons with his fpare pills, of which he feemed very defirous to know the compofition, having fome idea, as I fufpected, upon the ftrength of his experience of their virtues, of trying his fortune in the practice ofjnedicine. IV. December, 1788. John Bucknall, la- ^irer, of Kemberton, near Shifnall, Shrop- fhire, CALCULOUS COMPLAINTS. 19 (hire, has had the gravel for thirty years, and very violently for the laft fix or feven years. In harveft the pains at his loins have always been moft fervere, efpecially when he was reaping or mowing, a kind of labour which his diforder has often rendered him incapa- ble of following. The harveft beer is feldom without fome degree of acidity, to which he imputes, in a great meafure, the feverity of his fufferings at that particular feafon. The attitude of a mower or a reaper may, however, alfo account for this aggravation. He was directed to take a drachm of cryf- tals of fal fodae diffolved in three half pints of water. I believe, however, he much exceeded this dofe, as the common people are fo apt to do. In three days he per- ceived an increafe of his urine, and a great deal of red gravel came away. He had now the fenfation of a large lump in his right groin, which in about nine days totally difappeared. January 11, 1789. He confidered him- felf as totally cured. He was ordered to D 2 take 2« METHOD OF TREATING take every day, for a month, a fcruple of the fait diffolved in water, at two dofes, and afterwards to repeat the medicine in the fame dofe, one week at leaft in every month ; and if he found the quantity too fmall to prevent the return of his diforder, to regulate the treatment of himfelf accord- ing to his feelings, which a little expe- rience would foon enable him to do. I did not fee him again till May, 1792, when he told me that he had long totally difcontinued the folution, and that he had been perfectly free from any gravelly fymp- tom till within a few weeks, when he per- ceived a ftiffnefs in his loins, and fome other indications of a return of his diforder. I recommended to him the pills, but have heard nothing further concerning him. I met with one patient who would not ex- change the folution for the pills. He is the only perfon I have feen, who thought the tafte of alkali not difagreeable. V. The CALCULOUS COMPLAINTS. V. The cafe of Mr. Roe, timber-merchant, at Newport, in Shropfhire, was remark- able, on account of the violence of the fymptoms, and the extreme irritability of the patient's .habit. He complained of violent pains acrofs his loins, accompanied with ficknefs and vomiting, and intolera- ble fufferings immediately after the dif- charge of his urine, and a conftant irrita- tion of the bladder and urethra. He had from time to time difcharged much gravel, and many calculi as large as horfe beans. He was not able to ride without making bloody water. More than one of the for- mer patients had mentioned this circum- ftance ; but I believe the coffee-coloured is often miftaken for bloody urine. Early in 1789 he took half a drachm of cryftallized foflil alkali, wkh three or four METHOD OF TREATING four grains of cream of tartar * every day for three weeks. His pains were ien- * I then thought that the addition of a little cream of tartar to the alkaline folution, at the time of taking it, would gradually extricate fome fixed air in the ftomach and fecure the faturation. I even fuppofed -that I might, by a few experiments, difcover fuch a propor- tion of thefe ingredients a s would effect, without any apparatus, a fuperfaturation of the alkali that fhould remain uncombined with the acid of tartar. But the pills fuperfeded the neceffity of further refearches. On the addition of five or fix grains of cream of tartar to a fcruple, or a fcruple and a half, of fodse, diffolved in twelve or fourteen ounces of water, clofing the mouth of the phial, and inverting it in water, the alkaline folution acquires a much lefs difagreeable tafte than a mere folution of equal ftrength has, at the moment of unclofing the phial, an effort of protrufion is felt, and a few air bubbles afcend. The neutral fait thus formed would itfelf be probably beneficial ; I cannot believe, at leaft, that the carbonic acid contri- butes, by any direct operation, to the cure or palliation of the difeafe, fince cauftic alkaline fubftances clearly feem, if they could be fafely taken, to have equal efficacy with the carbonated -, and whatever be the effect of this acid, fome of thofe other acids, that are eafily dif- lodged from alkalis, would produce it equally. A re- fpedtable obferver (Menghini, Comment. Bonon. v. 61, Sec.) recommends Rochelle fait in calculous cafes. fibly CALCULOUS COMPLAINTS. 23 fibly diminifhed, and the pills were now fubftituted in the place of the folution. In a letter dated March 23, 1789, he de- fcribes himfelf as taking the pills : ', And ' tolerably well all the time, with now and ' ' then fome little pain, after which a fmall ' quantity of fmall gravel comes away.' In a letter, dated 12th April, 1789, Mr Jones who attended him, fays, ' There is no doubt ' as to Mr. Roe's cafe ; 1 am very happy 1 to inform you that he continues much ' better.' He took the pills regularly, felt from time to time fome flight pains or intimations of pain, after which fome gravel was difcharged. In April, 1792, he called upon me to inform me that he had enjoyed eafe and a good ftate of health fince I had heard from him laft. VI. The follow ingletter contains an account of a rare irritability of the urinary organs. The medical reader will certainly adopt the writer's 34 METHOD OF TREATING writer's opinion, that it is not a calculous cafe. I ought perhaps to have fuppreffed the conclufion of the letter; but as the fervour of expreflian, doubtlefs, correfponds to the pain the writer was once accuftomed to fuffer, and the relief he afterwards ex- perienced, it is properly to be confidered as defcriptive of the cafe, efpecially as I have not the fatisfaction of knowing the perfon who gives fo much credit to the me- dicine : * Sir, ' At the requeft of my brother-in-law, ' Mr. Biddle, I take the liberty of inform- 6 ing you of the effect which the alkaline ' pills, recommended by you, have inva- 1 riably produced upon me ; but it is ne- c ceffary to premife, that my cafe appears ' to me of a very dubious nature, as both 1 the quantity and quality of the fubftance ' which I fometimes void by Urine are in- c fufficient to convince me that my com- ' plaint is the gravel. But of that Sir, ' you may better form an opinion, when I 2 ' mention, CALCULOUS COMPLAINTS. 2; mention, thata quantity of wine, by no means intemperate, generally produced fo much pain in my kidneys, that to ftoop, or in any manner bend my back, was impoffible ; nor could I eafily turn myfelf in bed while this pain lafted, which moftly lafted a week or two, though by drinking plentifully of diluting liquors I made water without difficulty; yet the laft few drops, and fometimes the quan- tity of a tea cup full, were very bloody, and came from me with excruciating; pain ; but I never difcovered any gravel, and it appeared to me more like the mu- cus of the bladder : however, it more often happened that I had this fixed and intenfe pain in the fmall of my back, without voiding any thing extraneous in my urine ; and I am ftill very liable, after the ufe of wine, to returns of it, but fince Mr. Biddle has recommended it to me to try your pills, I have never failed, by ufing them for a day or two, or at farrheft in the courfe of a week, to obtain effec- tual relief. e < Thefe, 26 METHOD OF TREATING ' Thefe, Sir, are all the particulars of ' my cafe, which is not important enough 6 to merit much attention, nor perhaps ' will it help much to eftablilh the foffil ' alkali as a fpecific for the gravel, but to ' me it is a valuable difcovery, and I have c no doubt, when it is generally known, ' but it will be beneficial to thoufands. I ' beg your pardon for the prolixity of this * trifling detail, and earneftly defiring that ' you may obtain from others the praife ' and gratitude you have won from me, ' and that all your labours may be crowned ' with fuccefs, to the promotion of your * own fame, and the happinefs and im- • provement of your fellow creatures, I ' beg leave, Sir, to fubfcribe myfelf, * Your much obliged and ' verv humble fervant, 1 I,cr,:bard-flrcet, 7 .>,„.«, V 5 'D.LLOYD. Dr. Beddoes, Oxford. The CALCULOUS COMPLAINTS. 27 The relation of the other facts that have fallen under my own notice would be ufelefs repetition. All the patients for whom I have directed the foflil alkali have been pa ft, and moft of them confiderably paft, the prime of life. Calculi are fometimes found in the bladders of children, but the nephritis calculofa feems to be one among the evils ahnoft peculiar to declining age. Yet the foflil alkali, whatever were the infirmities of thofe who took it, and in fome inftances they were very great, has always been perfectly harmlefs, and, but in one cafe, decifively beneficial in its effects. The following communications will pro- bably be confidered as ftrong additional proofs of its efficacy : ' Dear Sir, ' I had the favour of your letter, and * am happy to hear it is your intention to * o-ive the world your fentiments upon c the efficacy of fal fodae in calculous dif- E 2 ' eafes. 28 METHOD OF TREATING c eafes. I am {o well convinced of its ' good effects, that I look upon it as a ' valuable acquifition. As I write chiefly ' from memory, I fhall not be able, pro- ' bably, to furnilh you with all the cafes ' that have fallen under my obfervation, c but the few I have recollected you may ' depend upon the accuracy of. The pa- ' tient, whom you enquire after, took it but ' a few days, loft his pain, and has fince ' had no return. _ ' Your thoughts upon fea fcurvy will c be interefting to every one, but parti- * cularly fo to our failors and naval pradti- 1 tioners. I have met with a few cafes (I ' think three) in this neighbourhood, but ' they were foon cured. * I am your obedient fervant, 'J. JONES. ' Newport, 1 ( 25.Feb. t79LJ *' CASE CALCULOUS COMPLAINTS. 29 'CASE I. 1 January, 1789, N. N. had been for ' feveral years afflicted with gravel, had 1 frequently violent fits of pain, and for c fome weeks paft has fcarcely ever been * totally free j has with vaft difficulty voided ' feveral large ftones. He took fifteen ' grains of fal foda, with one of magnefia, c and cryftals of tartar, twice a day for a ' fortnight; afterwards about feven grains ' of the dry powder of fal foda, with as 4 much foap formed into pills, for a fortnight « or three weeks longer regularly. He foon 1 difcovered a large mucous and very ropy ' fcdiment in his urine, and a great abate- c ment of pain • his fits returned at much 4 longer intervals, were fhorter, and much c lefs violent, and the ftones he voided ap- * peared half diffolved, which before had ' been liard and rough, and when dry { feemed to be covered with a fine foft * powder. In fix o^* feven weeks he be- ' came fo entirely free from his difeafe, ' that 30 METHOD OF TREATING 4 that he omitted his medicine for fome c months, and has fince had recourfe to it 8 occafionaily only for a fortnight at a ' time. He has never fince had a fevere { fit, but now and then, perhaps once in ' three or four months fome flight pain, 4 and then voided foftened ftones, more * like pieces of hard clay than calculous 1 concretions. « CASE II. 4 Mr. S. a farmer, who had lived 4 freely, had been long tormented with the ' frequent pafling of ftones from the kid- 4 neys. I w&s twice called to him, when 4 they were fo large as to flick firmly in 4 the urethra, and were removed with con- ' fiderable force by a pair of forceps, con- 4 trived for the purpofe, upon the principle 4 of Smellie's midwifery forceps ' He had taken various medicines with- 4 out any good effect, and upon that ac- * count CALCULOUS COMPLAINTS. 31 4 count was with difficulty prevailed upon 4 to try the fal fodae. In April, 1789, I 4 give him the dry powder with foap (31J. 4 of each in fixty pills) of which he took 4 two twice a day for hear a month, from 4 that time he has totally difcontinued 4 them, and when I laft faw him (Oct. 1790) he had never had a return of his 4 complaint that he thought worthy of 4 attention. 4 CASE III. * In January, 1790, I was called to a ' farmer at fome diftance from me, who * had for fome years fuffered much from 4 a ftone in the bladder. He informed me ' that he had taken a variety of what are 4 called folvents, without the lead advan- 4 tage. He had now been for fome time 4 confined to his room, and had fcarce 4 any refpite irom pain. Under fuch cir- * cumftances I faw no profpect of relief, 4 but irom the operation, which I ftrongly 4 recommended 32 METHOD OF TREATING f recommended to him. He could not * be prevailed upon to fubmit to it, 1 but was very defirous of trying any * medicine I fhould propofe. The extra- ' ordinary efficacy of the fal fodse I had * feen in the laft cafe, induced me to try 1 its folvent powers in this. >. 4 He began upon it immediately, and 4 took the ufual dofe twice a day for fix ' months regularly. In the fpace of a few c days his pain abated; in a month he was c able to walk about his farm ; and in the 4 courfe of the fummer walked feveral e times ten or a dozen miles in the day. 1 He ftill continued the pills, but with lefs 4 regularity, fometimes omitting them for 4 three or four weeeks ; and when I laft faw 4 him, which was in October, remained more 4 comfortable than he had been for the laft * two or three years. 2 ' CASE CALCULOUS COMPLAINTS 33 4 CASE IV. 4 B. a neighbouring farmer, about 7$, 4 has been for fome years tormented with a 4 ftone in the bladder. He had now(March, 4 1790) been for fome weeks unable to leave * the houfe,and in frequent and violent pain. 4 He took the fal foda2 pills ; in one week 4 his pain was much relieved, and in a ihort 4 time he was able to go about as ufual. He 4 ftill ^continues much better, and able to 4 ride gently, but is feldon many days with- ' out fome pain. He foon became tired of 4 the pills, and in the whole did not take 4 them more than a month.' Dr. Beddoes, Oxford. In a letter dated June 16, 1792, Mr. Jones informs me, that of thefe patients the third has fince died of another difeafe, and of the fourth, the fymptoms have feveral times recurred, and that with far lefs feve- rity than formerly. He had recourfe to the i" medicine 34 METHOD OF TREATING medicine a fecond time,c but it produced 4 fuch violent hea1 in his ftomach, that he 4 could not perfevere ; he continues how- 4 ever much better than he ufed to be, 4 and able to ride about his farm.' ' I 4 have,'continues my orrefpondent, 4 given 4 the pills in feveral more cafes of gravel 4 in the kidneys, and always with .fuccefs.' I have recommended for the lafl patient the folution with cream of tartar, and, if that fhould fail, the impiegnated alkaline water. The following letter will be found parti- cularly interefting, as it affords hopes of re- lieving a very diftrefling complaint, for which as for fo many others, we have no adequate remedy. 4 Shiffnal, fune^ 1793. * Dear Sir, 4 I am very glad to hear of your iaten- * tion to publifli your formula, with obfer- * vations on the foda, ?but can contribute 4 little to your flock of information upon 4 the CALCULOUS COMPLAINTS. 35 the fubject. You are already apprifed of my opinion of the great ufe of vegetable and foflil alkali in calculous concretions. No inftances having occured to me, wherein its effects feemed to deferve very particular remark, I am unable to offer more decifive or more favourable evidence of this medicine, than whatfprings out of the general refult of my experience. No opportunity has yet offered to me of try- ing its power as? a folvent of ftone in the bladder ; but in the nephritis ca'culofal have had abundant experience of its effi- cacy, both in promoting the difcharge of caltuli with eafe, and often in preventing their formation altogether. Yet amongft the many favourable proofs which prefent themfelves, I muft not conceal a few in- ftances, wherein the continued ufe of this remedy has, without any aflignable caufe, failed to procure relief. The proportion of thefe unfuccefsful cafes is but fmall, and as an additional alleviation, I can ad- duce fome proofs of the utility of the f 2 ' foda 3$ METHOD OF TREATI2 a ' foda pills in relieving biliary concretions, 4 which I know not if I have mentioned to 1 you before, and if not, two of them you 4 may perhaps think deferving the trouble 4 of a lhort recital. In both cafes the pa- 4 tients were females, and far advanced in 4 years. In the firft inftance, the difeafe had ' exifted upwards of fifteen years, and re- * turned pretty regularly at intervals of fix 4 or eight weeks, and fometimes oftener; 4 the proxyfms occurred with violent pain, 4 which ufually lafted many hours ; the fkin * became deeply tinged with yellow, and 4 after a day or two, a flight diarrhoea feem- * ed to relieve her. With fome difficulty I 4 perfuaded her to try the remedy, which * was made into pills with foap, and a few 4 drops of oleum nucis niofchatae were 4 added. Upwards of three years have now c elapfed fince flie had any return of the 5 fymptoms. The other lady had fuffered * extremely from fucceffive fimilar attacks, » and was relieved about eighteen months / ago by the fame remedy, but is under the ' ncceflirv CALCULOUS COMPLAINTS 37 * neceflity of a regular perferverance in the 4 ufe of it, 4 Believe me, Dear Sir, &c. &c. 4 W. Y O N G E.' Dr, Beddoes. Several queftions of great difficulty and fubtlety may be propofed reflecting the operation of alkaline fubftances in fuch cafes as the preceding. 1. Do they merely pro- duce the expulfion of concreted matter ? or do they excite fuch an action of the uro- poietic ©rgans, as tends firft to produce, and then to expel this matter ? I am difpofed to adopt the former fuppofition ; fince con- cretions are often lodged in the paffages without exciting any pain, and fince I have oftener than once witneffed the difcharge of fmall calculi about the probable period of the beginning operation of the medicine.— Do alkalis act as lithorttriptics or otherwife? In feveral cafes, as that of Bramah, they cannot be eafily imagined to have any fuch operation. 3$ METHOD OF TREATING operation. The ejects' are" much too fud- den; the fpeedy and confiderable difcharge of gravel makes it probable that they pro- duce, in the pelvis of the kidney or ureters, fome movements, which obfervation fbews to be by no means neceffarily connected with an increafed fecretion of urine. When the patient feels this kind of irritation too fen- fibly, the dofeofthe medicine riluft be re- duced, hi fome inftances, folution feems realty to have taken place, as in Cafe ift, related by Mr. Jones ;• arid many fucli are to be found on record. Our fecretioris may, it" fhoukl feem, be altered, either by altering, the action of the fecretbfy organ, or by presenting to it materials different from thofe which it has been accuftomed to work upon. The uritie, by whatever caufe, is remarkably changed : we are informed on very refpectable authority, that the urine firft made after a dofe of mephitic alkaline wa- ter, 4 will change turnfole paper to a blue 4 colour, even if it be not taken above a 4 quarter of an hour befofe the difcharge of ' the CALCULOUS COMPLAINTS. 39 * the urine*.' I wifh fome other tell: of alkalis had beenufed: and ftill more, that thofe who have an opportunity of watching the progrefs of patients under a courfe of alkaline medicines would afcertain— 1. Whether the blood undergoes any de- terminate change.—2. Whether the urine becomes habitually alkaline—3. Suppo- fing this to be the cafe, and the patient to take vegetable alkali, is the excefs of alkali in the urine, vegetable, or foflil, or volatile \ Many other equally curious points of in- veftigation would arife in fuch an enquiry. Of all the fecretory organs, the kidneys and the mammae are moft certainly and quickly affected by the paflions and by food. By ftudying the analogy that fubfifts between thefe organs, and by experiments not difficult to be contrived or executed, it is probable that we may acquire a confiderable acceflion of ufe- ful knowledge on a fubject little underftood. * Account of the Efficacy, 3d edit. p. 117. Ordinary urine is known to be acid: Mr. Berthollet, the great Parifian chemift, has obferved the quantity of this acid tu be much increafed by certain diforders. 1 O B S E R- Obfervations and Conjectures On the S C U R V T, On obesitt, On PHTHISIS PULMONALIS, AND On CATARRHS. AN one or two difeafes, the patient is apparently directed by a fort of inftinct to the means of cure : in all other inftances, remedies muft have originally been the pure bounty of accident. A few facts, however, would fet fpeculation to work ; and in pro- portion as the number offubftances capa- ble of producing confiderable changes upon the living fyftem increafed, the data for anlaogical reafoning in medicine were mul- tiplied. It is, in fact, only by feizing thofe new analogies, which are offered from time to time by difcoveries in the phyfic^l feiences, G that yz OBSERVATIONS ON THE that we can hope to improve the art of me- dicine. Nor will any one, who will take the pains to comprehend this firnple truth, require an apology for attempts to form new combinations of this fort. Mayow not only difcovered feveral elaftic fluids, and the effential properties of the moft active of them all, but he afpired to change the whole face of medicine and phy- fiology, by the application of his wonderful difcoveries to the appearances of animal na- ture. Immediately upon the revival of this branch of chemiftry, Dr. Macbride attempt- ed to derive the fame advantage from it, and the minds of fucceeding philofophe have been engaged by fimilar fpeculations. The two annexed papers of Dr. Girtanner afford an extremely ingenious fpecimen of fuch fpeculations. His experiments -are fe- veral of them happily imagined ; that by which he has at once fhewn the falfehood of the conclufion which Fontana had drawn from his laborious experiments on poifons, is SCURVY, OBESITY, &c. 43 is conceived in a fpirit far more philofophi- cal than that which has directed the greater number of experiments upon animals. His reafonings are an attempt to inveftigate the laws of organic bodies, by combining the medical opinions of Dr. Brown with Mr. Lavoifier's theory of chemiftry. He bor- rows little from Haller, befides the term irritability, and if he has not mentioned the name of Brown, he has made a free ufe of his doctrines, and often employed his very expreffions. He might not, perhaps, in an abftract, think it neceffary to point out the fource from which fo many of his ideas are derived, but in his larger work we have a right to expect that he fhould do juftice to departed genius. The yournal de Phyfique, from which thefe papers are taken, is indeed abundantly known to the cultivators of fcience, but it can by no means be fuppofed to fall into the hands of the majority of the practitioners of medicine in this ifland; and I was very willing to enchance the value of this little o 2 publica- 44 OBSERVATIONS ON THE publication by annexing to it a train of re- flections, in general well worthy of their notice, and calculated to excite their reflec- tions. Mr. Woodhoufe, of the Middle Temple, at my requeft, dedicated fome hours of leifure at Oxford to the tranf- lation, and his knowledge of the French, and of his own, language, would probably have concealed from the reader that he has not made phyfiology his peculiar fludy. For feveral years paft I had been attempting to difcover fome part of the effects of oxy- gene air upon the animal ceconomy : it ap- peared likely that its abundance or deficiency would fenfibly affect the health, and that the chemical compofition of the fluids and folids of the living body would influence their properties not lefs than the properties of dead matter, though not perhaps exactly in the fame way. In fome inffances I thought I perceived as much certainty as either could be expected, or as is any where to be found in medical reafonings, and in others there appeared a faint glimmering of probability, SCURVY, OBESITY, &c. 45 probability, where total darknefs has hi- thereto prevailed. The fcurvy (fea fcurvy) I have long confidered as offering an appli- cation of the pneumatic chemiftry, nearly as direct and beautiful as the phsenomena of refpiration ; and it would be eafy' to prove, by the teftimony of different perfons, that I had long fuppofed this difeafe to be owing to a gradual abftraction of oxygene from the whole fyftem, juft as death is pro- duced in drowning, by withholding all at once the fame fubftance from that blood which is to pafs to the pofterior cavities of the heart. The proofs of this theory feem- ed equally fimple and ftrong ; the livid co- lour of the blood, and the large livid fpots which are fo often fpread over the furface of the body, left little room to doubt of the abfence of oxygene ; and the recovery of the fick, by the adminiflration of acids, and by a vegetable diet, afford a fort of confirma- tion fimilar to that which is derived from chemical fynthefis, for no fubftances are better calculated than acids at leaft, tc im- part oxygene to the fyftem ; they contain it in abundance, and they eafily part with it. There 46 OBSERVATIONS ON THE There muft frequently be obferved by thofe who attend to the effect of evidence upon different minds, a fpecies of intellec- tual cowardice, which refufes its affent to juft evidence, as long as a fingle difficulty remains, though the facts conftituting this difficulty do not oppofe, any more than they coincide with, the theory. In hopes of clearing up fuch difficulties, and apply- ing the hypothefis to the principal fymp- toms, I from time to time deferred the publication of an opinion, in fupport of which I had collected various proofs^ In the mean time, the fame theory oc- curred to a phyfician, whofe acquifitions and powers of reflection do him the more honour, as the greater part of his life feems to have been fpent amid the hurry and in- commodioufnefs of a feafaring life.* Such an anticipation is very natural in the prefent * Obfervations on the Scurvy. By Thomas Trotter, M. D. 1792. In the firft edition of this ingenious trea- tife no fuch theory is hinted at. The firft edition was publifiied in 1786. period SCURVY, OBESITY, &c. 47 period of fcience, and however mortifying it may be to vanity, it affords the moft pow- erful encouragement to perfevere in attempts to afcertain the principles of the moft im- portant and moft imperfect of all the arts, inafmuch as it proves the poflibility of rea- foning fuccefsfully concerning a difeafe, which you fcarce know but by defcription. Dr. Trotter, (from page 125 to 150) ifates the leading circumftance in this dif- eafe, the privation or diminiftied propor- tion of oxygene in the blood. He quotes fome of the fine experiments of Dr. Good- wyn, and mentions the exiftence of oxygene in acids, which he juftly imagines, they re- ftore to the blood. He does not enter into any other particulars of theory. 4 The ratio- 1 fymptomatuml he mo deftly obferves, 4 is 4 certainly a difficult fubject to enter upon. 4 In wdiat manner a difeafed ftate of the 4 blood communicates its influence to the 4 moving powers of the body we are at a 4 lofs to explain.' It 48 OBSERVATIONS ON THE It may be expected of a theory framed by two perfons independently of each other, that the fhades fhould differ, although the outlines be the fame. My reflections on the fcurvy have been more minute, and, in many refpects, my conclufions vary from thofe of this experienced writer. I fhall leave to the reader's confideration the two leading proofs ftated above, and fo largely expatiated upon by Dr. Trotter, and add fome mifcellaneous obfervations, which may tend ftill farther to eftablifh the theory. I fhall alfo frankly intermix rhy objections to fome of his opinions, chearfully fubmitting it to his ample experience to decide between us, in a full expectation that his regard to truth and utility will abforb all perfonal confide- rations. I. In the firft place, it is not quite accurate to impute the difeafe to a deficiency of oxygene in the blood. The deficiency is, doubtlefs, general to the whole fyftem. The difcolouration of thofe of the folids, of which the colour evidently depends upon 2 oxygene, SCURVY, OBESITY, &c. 49 oxygene diftributed to them from the blood, befpeaks a deficiency here alfo. This difcoloration is noticed in moft of the accounts we have of fcurvy. ' The gums * have an unufual livid appearance,' fays Lind (3d edition, p. 100). In one paffage the heart is faid to be white and pu- trid, the lungs blackifh and putrid (p. 240) ; in another the mufcles are defcribed as mortified (p. 242), and as falling to pieces on being handled. Dr. Blane could not difcover, upon diflfection, any effufion of blood *, where the livid fpots appeared. Hence too it may be concluded, that the hardnefs and ftiffnefs of the mufcles and tendons, a fymptom generally obfervable in fcurvy, depend upon the abfcnce of oxygene. As oxygene is neceffary to the contrac- tion of the mufcles, it is probable that it is confumed, or, more properly fpeaking, enters into fome new combination, in * Obfervations on the Ti.eafes of Seamen, 1780, 11 confequence 50 OBSERVATIONS ON THE confequence of which it is eliminat- ed out of the body; for we cannot but fuppofe that the quantity employed correfponds to the vaft quantity imbibed. Hence we may underftand the final caufe of quickened refpiration, during great ex- ertions of the mufcles. This feems alfo to explain an obfervation which has fo frequently been made at fea, that the fcurvy makes its appearance after a ftorm, when the feamen, having undergone violent exer- cife, have expended a great part of the oxygene of the folids. 2. One of the moftpleafing, and, if I con- ceive it juftly, of the ftrongeft poffible ar- guments, may be drawn from fome appear- ances in the thorax after death. Dr. Good- wyn found, that in fuffocated animals the left cavities of the heart are full of venous blood. I have had abundant opportunities of verifying the truth of this obfervation. The death of fcorbutic patients frequently feems to enfue, in confequence of the blood being fo deftitute of oxygene, as to be in- capable . SCURVY, OBESITY, &c. 51 capable of ftimulating the left auricle and ventricle of the heart : perhaps alfo the inir- ritability of the mufcular fibres of the heart itfelf may contribute to this effect. The fol- lowing paffages will eftablifh the fact. 4 The * cavities of the heart were quite full of cor- 4 rupted blood.' Lind, p. 240. 4 All thofe * who died fuddenly, without any vifible 4 caufe of their death, had,' according to another account, 4 the auricles of their 4 heart as big as one's fift, and full of coa- 4 gulated blood.' p. 241. Dr. Lind, from his own diffections, men- tions' that 4 in patients, whofe deaths were 4 unexpected and hidden, and where no 4 effufion of blood could be perceived into 4 any cavity of the body, the heart was 4 commonly much diftended with blood ; 4 the auricles and ventricles of both fides 4 were filled, but thofe on the right in the * greateft degree.'p. 503. This phsenome- non would engage Dr. Lind's attention the more, as he was aware that though the right ventricle • after death is generally dif- h 2 tended 53 OBSERVATIONS ON THE tended with blood, * the left feldom con- 4 tains any.* p. 503. This want of ftimulating power in the blood, and of irritability in the heart, will perhaps account for the fymptoms fo often mentioned, anxiety, tightnefs of the breaft, difficulty of breathing. 3. Dr. Trotter confiders, * a deficiency * of recent vegetable matter alone, as the 4 occafional caufe of the fcurvy.' p. 171, 172. Yet we are certain that the blood, in the firft inftance, and afterwards the folids, are oxygenated by means of the lungs. They may acquire this principle by means of the ftomach; but we have no direct experience of their doing fo. It is only an inference from the compofition of acids and vegetables, and from their effects in the fcurvy. Between the reception of any given food into the ftomach, and the oxy- genation of the blood by that food, there muft intervene unknown proceffes. It ap- peared therefore probable to me, that as feamen SCURVY, OBESITY, &c. 53 feamen in general breathe an air contain- ing a fmaller proportion of oxygene than any other defcription of perfons, the fcurvy might often originate from this caufe, and may be prevented or cured by guarding againft it; for whether we oxygenate the blood by the lungs or the ftomach, a dif- eafe depending on the want of this princi- ple may, one would fuppofe, be equally obviated ; nor would it be eafy in the pre- fent ftate of our knowledge to affign any circumftance that diftinguifhes the two cafes, except the heat fupplied by oxygene, when prefented in the ftate of an elaftic fluid, though it would be rafh to deny that other differences may exift. Captain Cooke's unexampled fuccefs in preferring his crews from the fcurvy during his two laft voyages, feems in great meafure owing to his extreme care to keep his fhips well aired. On many occafions they were reduced to fait provifions, and much longer out of fight of land, than many other fhips, which have been dreadfully afflicted with the fcurvy; in his laft voyage there never 54 OBSERVATIONS/ON THE never appeared among his crew any fymp- tom of this d4forder ; and in his fecond only one man had it in any confiderable de- gree. 4. It is extremely difficult to find fuch pre- cife facts as fhall amount to an experimentum crucis, efpecially as obfervation has not yet been guided by this theory. But Dr. Trot- ter has himfelf furnifhed an important ob- fervation, from which, if any one were to decide between thefe two caufes of fcurvy, want of frefh vegetables, or want of air fuf- ficiently furnifhed with oxygene, he mull, I think, decide without hefitation in favour of the latter ; and here I appeal to Dr. Trotter againft himfelf. In July 1783, a fhip, of which he was furgeon, arrived at Cape La How, on the Gold Coaft of Africa. In the fpace of a week above ' an hundred prime 4 flaves, young, ftout, and healthy,' were purchafed. The competition however of the purchafers at Anamaboe, whither this fhip afterwards failed, ran fo high, that in February, 1784, it had not on board two thirds SCURVY, OBESITY, &c. SS thirds of its complement. An indifpofition now began to prevail among the flaves, which foon afterwards proved to be the fcurvy ; and before the arrival of the vef- fel at Antigua, of near fix hundred and fifty, near fifty had died, and about three hundred were tainted, in different degrees, with the fcurvy. Before they quitted the coaft, feven or eight had died, and be- tween feventy and eighty were ill. i. Of thefe flaves, 4 the food confifted 4 of beans, which were brought from Eng- 4 land, and rice and Indian corn, which 4 were bought on the coaft. Thefe arti- 4 cles were boiled to the confiftence of a 4 foft pafte, and made as near as p©ffible 4 like the food of the country, by the ad- ■ dition of palm oil, Guinea pepper, and • common fait—they were allowed to drink * what water they pleafed.' p. 52. 2. They were 4 confined below fixteen * hours out of twrenty-four, and permitted 1 no exercife when upon deck.' (ibid.)4 The ' rooms. 56 OBSERVATIONS ON THE 4 rooms, where they are fecured below, are 4 from five to fix feet in height. They * are flowed fpoonways, and fo clofely ' locked into one another's arms, that it is 4 difficult to move without treading upon 4 /them. The rooms are imperfectly aired 4 by gratings above, and fmall fcuttles in 1 the fide of the fhip, which, of curfe, 4 can be of little ufe at fea. The gratings 4 are alfo half covered when it blows hard, 4 to keep out the fait fpray or rain. The * temperature in thofe rooms, when they 4 become crowded, was above 96°ofEah- 4 renheit's fcale.— I myfelf could never 4 breathe there, unlefs under the hatchway. • In fuch fituations it may be fuppofed, 4 that the fufferings of thefe creatures are 4 fometimes dreadful. Air, heated and c rarified to fuch a degree, and loaded with 4 animal effluvia, cannot fail of being nox- 4 ious to life. There were certainly in- 4 ftances where fome expired from fuffo- 4 cation, having fhewn no previous fign c of indifpofition.' p. 54, 55. -o 3. With SCURVY, OBESITY, &c. 57 3. With thefe two fa&s, let the rea- \ der compare the following: 4 Few of the 4 boys had any fcorbutic fymptoms ; none ' of them were fhackled; and by being 4 allowed to run about the deck, and occa- 4 fionally affift in the duty of the fhip, 4 their health feemed to be preferved by 4 the exercife. This was alfo the cafe 4 with the women, for out of the whole 4 number eight only were affected.' (p. 63.) 1 During this fickly ftate of the fhip, none 4 of the failors were in the leaft tainted 1 with the fcurvy. Their diet was the * common fea fare; a little of the victuals 4 prepared for the flaves was generally eat 4 with the fait beef; they had it however in 4 their power * to barter fome of their pro- • virions with the natives for frefh vegeta- 4 bles.'p. 64. The following is the inference which they author draws from thefe facts : 4 I am ex- 4 tremely unwilling to admit the conta- * Did they all make ufe of the opportunity ? I * gious S'8 OBSERVATIONS ON THE 4 gious nature of this difeafe ; and if it 4 cannot be propagated that way, it is 4 moft likely that the tainted atmofphere 4 of the flave rooms, which were now full, 4 fo powerfully predifpofed thofe late pur- 4 chafed negroes to fcurvy, that the ex- 4 citing caufe was much accelerated in its 4 operations, by the foul air which they 4 breathed ; impure exhalations have there- 4 fore been defervedly mentioned by au- 4 thors among the remote caufes of the • fcurvy.' p. 68. For my part, I fhould prefume that the diet of thefe unhappy peo- ple could have no fhare whatever in pro- ducing the difeafe,' which delivered fo many among the men from their prefent and impending calamities. 5. Tliere are other facts which feem to ihew that too much is attributed by Dr. Trotter to frefh vegetables. Linnseus in- forms us, that the Laplanders are unac- quainted with the fcurvy; they feed all the winter on the frefh flefh of the rein- deer. 4 This exemption of the Laplanders ' from SCURVY, OBESITY, &c. 59 4 from the general diftemper of the north,' fays Pringle, * is the more obfervable, as 4 they feldom tafte vegetables, bread never.' (Cook's Voyages, from 1772 to 1775. vol. ii.p. 376.) Confidering frefh meat, or the mufcular part of animals, chemically, I fee no rea- fon why it fhould not be efficacious in preventing or curing the fcurvy. Oxygene it contains, when raw, in a ftate of loofe - combination, though probably not in fuch large proportion as vegetable fubftances, even fuch as are not acid. I had noticed in travellers of great refpectability paffages that confirm this idea. The nations inha- biting the cold and dreary regions on the eaftern lhores of Afia, and the oppofite coafts of America, feem to have learned from experience, that frefh, or at leaft un- falted fifh is a preventive of the fcurvy, or a remedy for it. Thus Dr. Pallas (Reife, iii. 47.) defcribes the Oftiack Tartars of the Oby, as preparing their wTinter ftores altoge- 1 2 thcr 60 OBSERVATIONS ON THE ther without fait. 4 They are extremely apt, 4 when difabledby age or infirmities, to be- 4 come fcorbutic. In winter they ravenoufly 4 devour their frozen fifli raw, a practice ' which the neighbouring Ruffians imitate, 4 efteeming them a prefervative againft the ' fcurvy.' (46.) Mr. Meares( Voyage, Introd. p. 30.) fpeaking of an American tribe, fays, 4 She made us fenfible that the fame dif- 4 order (fcurvy) prevailed in her nation; 4 and that whenever the fymptoms ap- 4 peared, they removed to the fouthward, 4 where the climate was more genial, and 1 where plenty of fifh was to be obtained, * which never failed to prove the means 4 of their recovery.' The reader will probably agree to confi- der the frozen as frefh fifh. If it were poffible to preferve meat on fhip board, in this fimple manner, one great fource of the fcurvy would probably be cut off. Cookery combines the oxygene anew ; would our failors eat raw animal food ? Dr. SCURVY, OBESITY, &c. 61 Dr. Lind, though he has full confidence in green vegetables, and affirms that the fcurvy never can 4 become a general, fa- 4 tal, and deftructive calamity,' where they abound, and the proper method of treatment is known and purfued (p. 541.) ; con- cludes from a number of comparative trials (p. 538), that certain patients in Haflar hofpital in general grew better, notwith- ftanding they abftained altogether, from ve- getables. 4 This ftrict abftinence from the 4 fruits of the earth,' fays he, 4 was conti- 4 nued long enough to convince me, that 4 the difeafe would often, from various cir- 4 cumftances, take a favourable turn, inde- 1 pendent of any diet, medicine, or regimen.' We have nothing, I prefume, to oppofe in point of conclufivenefs to fuch experi- ments made by a phyfician fo intelligent and fo experienced in this particular dif- eafe. The following cafe, for which we are indebted to Dr. Sandifort, Profeffor of Anatomy at Leyden, is among the moil extra - 62 OBSERVATIONS ON THE extraordinary in the records of medicine. Its value however exceeds its Angula- rity. Dr. Goodwyn quotes it in fupport of his doctrine of refpiration. It no lefs corroborates the foregoing theory. After the local fymptoms arifing from the con- formation of the heart are fet afide, there will remain the principal characteriftics of fcurvy, livid fpots or blotches, a bloated countenance, haemorrhages, exceffive laffi- tude, diftreffing anxiety, frequent faintings upon flight motion, and a very offenfive breath, without an impaired appetite, and with a tendency to falivation. Diftinct as the account is, I wifh for ftill greater minute- nefs, in a firm perfuafion that every additional circumftance, by affording a new analogy, would tend ftill further to fhew that the fymptoms of fcurvy arife from a deficient fupply of oxygene to the blood by way of the lungs. For nearly the firft year of the life of the infant in queftion, who was born November 17th, 1764, there was no appearance of difeafe. The parents were healthy; the child was put out to nurfe; he SCURVY, OBESITY, &c. <53 he grew apace; l but was fcarce a year 4 old *, when thofe dreadful fymptoms, • which fo much harraffed him during the 4 fubfequent portion of his life, manifefted 4 themfelves. The livid colour of his ' nails and fingers firft drew the attention 4 of the parents. This hue was not con- 4 ftant; it was not occafioned by any 4 tightnefs of drefs ; it did not at firft ap- 4 pear of fuch confequence, as to induce 4 them to call in a phyfician, efpecially * as the child feemed in other refpects 4 healthy1, and made fuch progrefs as to be 4 able, by the end of the fecond year, to 4 walk alone. 4 He now began to complain of great * laffitude upon the leaft exertion. A * catarrh, accompained with a violent op- 4 preflive cough came on. The child ob- 4 ftinately refufed the medicines prefcribcd ' by the phyfician, who was now called 4 in, and the next day a number of fpots, * Obfervationes Anatomico-Pathologicae, Lugd. Batav. 1777. p. 11, &feq. which 64 OBSERVATIONS ON THE 4 which at firft were of a red colour, and 4 then turned livid, were obferved upon 4 the face. The cough continued trouble- 4 fome; motion became exceedingly dif- * agreeable; and after any fatigue, the 4 face, hands, and feet appeared remark- 4 ably livid; the tongue and lips were 4 nearly black, but the natural colour re- ' turned, upon remaining quiet fome time. 4 Thefe alternations were vifible almoft • every day. Meanwhile the child grew 4 rapidly ; the appetite was very good, and * there was no complaint, but of laffitude, 4 preffure on the top of the head, anxiety, 4 efpecially in winter, and fuch chillinefs, 4 even internal, that in winter he could 4 not keep himfelf wTarm by the fi re-fide; * nor did the rays of the fun, on the hottefl * days, produce their natural effect, much 4 lefe occafion any fweating. 4 March, 1767. Bleeding feemed to 4 leffen the anxiety and fenfe of preffure 4 for a time. The blood was thick and 4 black, and no craffamentum feparated. 2 4 Towards SCURVY, OBESITY, &c. 65 4 Towards the clofe of this year he had 4 the fmall-pox mildly, arid without any 4 aggravation of his anxiety; noi did the 4 mealies and chicken-pox, which he 4 caught a few months afterwards, produce 4 any change either for the better or the 4 worfe. . The fymptoms above mentioned 4 attacked him the moment he moved, 4 efpecially the anxiety, which was accom- 4 pained with fuch violent palpitation, that 4 the ftrokes of the heart could be feen, 4 and even heard. Riding which was now 4 recommended, proved of no fervice, nor 4 could he bear it long at a time. Gaubius, being confulted in 1769, ad- vifed cold bathing and rubbing the body, but to no purpofe; bleeding, and gentle motion were equally ineffectual; the anx- iety, when extreme, was attended with a dry cough. * The breath had an un- 4 common fmell, much refembling that 4 of an egg opened immediately after 4 boiling. K 4 This 66 OBSERVATIONS ON THE ' This diftreffing fituation continued till 4 1774, by which time the anxiety and 4 violence of the palpitations were much 4 increafed, and faintings, pain, like pref- ' fure, in the head, a fwelling and pulfation 4 of the jugular veins, were obferved. 4 Riding being utterly impoffible, frequent 5 airings in a Carriage were fubftituted in 4 its ftead. In May bleeding diminifhed *4 the anxiety; and he could now walk 1 about for an hour, without any great fa- * tigue, and his parents began to entertain 4 hopes of his recovery. But all the fymp- 4 toms recurred with greater violence in 4 autumn ; he coughed violently, and fpit 4 up, fometimes mucus ftreaked with blood, 4 fometimes pure blood. For this he was 1 twice bled in November, within four 4 days but the anxiety ftill continued, and 4 fometimes rofe to fuch a pitch, as to 4 threaten immediate death. The child 4 was fenfible that he fhould not long fur- * vive, he often remarked that his diforder ' was quite unknown and incurable, and 4 that SCURVY, OBESITY, &c. 6^ 4 that no perfon could conceive what he 4 felt about the heart. Another bleeding 4 in December afforded a tranfitory relief; 4 but the fetting in of winter, a feafon al- * ways intolerable to him, excited the ut- 4 moft alarm in the parents.' During the following year, the com- plaints continued equally diftreffing. In 1776,'all motion became impoffible ; on 4 the flighteft exercife, he would faint, 4 difcharge a great quantity of faliva from 4 his mouth, and continue blind for a time ; 4" all attempts to relieve him were vain ; 1 the anxiety was much increafed, efpe- 4 cially on laying down ; what had formerly 4 amufed him now became indifferent; his 4 face was bloated ; his feet became cedema- 4 tous; yet his life was protracted in mifery to 4 the 8th of March, 1777, when, upon being * feized with exceffive anxiety, he died.' Dr. Hahn, who attended ru'm during the laft year, communicated to Dr. S. the fol- lowing particulars : k 2 l Immediatclv 68 OBSERVATIONS ON THE 4 Immediately upon the very firft glance, I 4 recognized the complaint of which I had 4 heard fo much, and which report, as 4 ufual, feemed to have exaggerated : the 4 child was afthmatical ; on the flighteft 4 motion he breathed with fuch difficulty 4 that his face and hands became as livid 4 as in a ftrangled perfon ; fometimes they 4 looked as if painted blue. 4 The eaufe of fo fevere and fo long 4 continued an afthma was obfeure ; nor 4 did it appear certain when the difeafe 4 began. The parents, and the phyfician 4 who had hitherto attended him, agreed 4 in affuring me, that he was born healthy, 4 and that no figns of complaint in the 4 cheft had occurred during the firft year; 4 nor was it till the fecond year that the 4 blue colour and fymptoms of afthma had 4 been obferved ; even then the complaint 4 was not conftant, but became worfe and 4 worfe, as the patient advanced in years * and fize. ' The SCURVY, OBESITY, &c. 69 4 The child feemed to me handfome, 4 well-made, and tall for his years. He had 4 a conftant difficulty of breathing, which 4 increafed in cold weather, and upon mo- 4 tion ; the face was bloated ; the eyes 4 were protuberant, fixed, and betrayed un- 4 eafinefs. While the afthmatic fit con- 4 tinued, his face appeared as it ufually 4 does in a perfon who has been long walk- 4 ing apace againft the wind in winter ■ 4 the cheeks, point of the nofe, the ears 4 as well as hands, fingers, and nails be- 4 came livid ; the lips, tongue, and infide 4 of the mouth were of a .deep purple; 4 the pulfation of the carotids was vifible 4 at a diftance; the pulfe at the wrift very * fluctuating. 4 The child was fenfible; his temper 4 variable; but he was commonly morofe 4 and peevifh; during his lhort intervals of 4 chearfulnefs, you could difcover in his 4 eyes and on his forehead, even while he 4 fmiled, a latent fenfe of fuffering ; dif- •4 ferent complaints were perpetually ?;,> ' currin^, 70 OBSERVATIONS ON THE ' curring, as head-ach along the fagittal 4 future, ear-ach, pain in the breaft and 4 left hypochondriac region, of ficknefs, 4 pain in the belly, extending as low as the ' os pubis, chillinefs, &c. * At different times his fufferings varied 4 confiderably. The following circum- 4 ftances I conftantly obferved : 4 i. Great dyfpncea upon motion j vifible 4 pulfations in the neck. 4 2. A face too full for the habit of the * reft of the body; during his laborious 4 refpiration a livid colour of the coun- 4 tenance, a protuberance, and occafional 4 fuffufion of the eyes. 4 3. Urine always high-coloured, with- 4 out fediment. 4 4. Great coftivenefs. c 5. Conftant chillinefs, even though 4 the SCURVY, OBESITY, &c. 7, 4 the fkin felt warm ; this fenfation never 4 left him, except after he had become 4 quite warm in bed. In winter, though 4 fitting clofe by the fire, he complained of 4 fhivering, and in fummer he longed for 4 a large kitchen fire, and defired to balk 6 in the fun during the, hotteft part of the c day. 4 6. He was fometimes much relieved * by opening medicines and by hsemor- ' rhages from his nofe, which happened * from time to time. 1 The tongue was very foul; the breath 4 extremely offenfive (faetidiffimus)? After quoting fome cafes, not, I think, altogether in point, Dr. S. gives the follow- ing account of the diffection. The thorax alone was opened. 4 The pericardium did not, as ufual, 4 appear furrounded by the lungs, and al- 4 moft inclofed in them ; but a mafs was 4 feen 72 OBSERVATIONS ON THE 4 feen to fill nearly the whole cavity, and 4 to comprefs the lungs extremely : this 4 mafs was the pericardium, containing the 4 heart in a ftate of great diftention, and 4 very full of blood. It reached from the 4 diaphragm (which on the right fide rofe 4 to the fifth, on the left only to the fixth 4 rib) to the fpace between the firft and 4 fecond rib, and fo entirely filled the late- 4 ral parts of the thorax, that only the an- ' terior portion of the lungs on the right 4 fide (viz. the margin of the fuperior 4 and middle lobe), and but a very fmall 4 portion on the left (viz. towards the 4 upper and lateral part) could be feen. ' Above the pericardum, the fuperior 4 cava, wTith the origin of the fubcla- 4 vian veins, appeared turgid with black 4 blood. ' Upon opening the pericardium, fome 4 water ran out ; but not more, indeed not ' fo much, as is fometimes found in fnb- 4 jedts where no dropfical fymptoms have 4 preceded death. ^ 4 The SCURVY, OBESITY, &c, 73 * The heart, when freed from its fack, 4 appeared exceffively turgid, not however * equably fo: both the ventricles were not 4 diftended to the fame degree; the right 4 ventricle, as well as its auricle and finus, 4 were much more enlarged, and full of * blood, than the left; all the veins, which 4 ramify from the coronary veins along the 4 furface of the heart, were fo dilated even 4 to their extreme branches, that the moft 4 fuccefsful injection could not have ren- fi dered them more diftinct. 4 The veins arifing from the fubclaviart, 4 more efpecially the jugular, were enor- * moufly diftended with thin black blood; 4 the fuperior vena cava, where it is 4 lodged within the pericardium, did not 4 much exceed its natutal fize ; the inferior 4 cava was enlarged ; the pulmonary veins 4 were turgid, but not exceedingly fo ; * the aorta was enlarged at its origin ; the • pulmonary artery was remarkably con- 4 tracted, from its origin almoft to its bi- • fur-cation >• of the arterious duct, or rather l 4 ligament, 74 OBSERVATIONS ON THE ' ligament, as it would have been at this 4 age, there was no veftige. 4 The lungs externally had no morbid 4 appearance; but they were fmall, com- 4 preffed, and not eafily dilatable; whence 4 it appeared that they could not properly 4 have performed their functions. 4 The external appearance of the heart 4 fhewed where the fource of the mifchief 4 lay. After tying up all the veffels, it * was fubmitted to further examination. 4 The right finus and auricle were firft 4 opened ; a large quantity of thin black 4 bldfffl flowed out. In the foramen ovale 4 there was an aperture, which would ad- 4 mit a large probe. 4 On introducing the finger into the right 4 ventricle, and turning the point towards 4 the orifice of the pulmonary artery, where 4 it ufually arifes from this ventricle, no ' fuch orifice could be felt, but it eafily < Aided SCURVY, OBESITY, &c. 7; 4 Aided into another, and that a very large 4 one. But how great was my aftonifh- c ment, and that of all the bye-ftanders, 4 when it was difcovered, that the finger 4 had paffed into the arota, which, accord- 4 ing to the ordinary law of nature, has 4 no communication whatever with the 4 right ventricle. 4 This ventricle was divided in the 4 place oppofite to the valve, behind which 4 the arterious orifice lies, quite down to * the apex. Upon lifting this valve a lit— * tie, the large mouth of the aorta ap- 4 peared, as alfo a fmooth margin; beyond 4 which the finger found a way into the 4 left ventricle of the heart. Upon cutting 1 the aorta tranfverfely, at a proper dif- 4 tance from the femilunar valves, the 4 fame margin was feen to divide its orifice 1 into two parts, the larger communicating • with the right, the fmaller with the left 4 ventricle. * The aorta therefore arofe from both l 2 * ventricles, 76 OBSERVATIONS ON THE 6 ventricles, and muft have received all the 4 blood from both. 4 The pulmonary artery having been 4 cut acrofs above the valves, they ap- 4 peared very fmall, almoft grown to the 4 artery, and covered with a granular fbb- 4 ftance, refembling a flefhy excrefcence, 4 fo that only area enough was left to 4 fuffer a fmall probe to pafs into the ven- ' triele, and even this paffed with greater * difficulty from the ventricle into the 4 artery. Upon opening the orifice longi^ * tudinally, we found only two fhapelefs 4 valves, partly covered with the fame gra- 4 nuiar excrefcence, 4 In the mouth of the arota there were 4 three valves; in the left ventricle there 4 was nothing remarkable, except the aper- 4 ture in the feptum, and the thinnefs of 4 its fubftance, which did not exceed, and 4 indeed fcarce equalled, that of the right r ventricle.' From SCURVY, OBESITY, £c. 77 From the feveral particulars of this won- derful hiftory and diffection, the reader will be able to draw fome importaint con^ clufioms, befides that already pointed out. 1. The comparative capacity and ftrength of the ventricles in this cafe confirms Dr. Goodwin's difcovery of the inirritabirity of the left ventricle by venous blood/ Here the right ventricle feems to have performed almoft all the labour of circulation : hence its enlargement, its equal or fuperior thick- nefs, the left not having, in confequence of action, outftripped it in this refpecti as it does in healthy perfons ; hence, pro- bably, alfo, the larger opening of the aorta into the right ventricle. 2. This cafe re- moves all doubt as to the neceflity . of oxy- gene to the due action of the mufcles ; a fact which the penetrating genius of Mayow perceived, though he mffconcerved the mechanifm of mufcular action-, which we do not yet underftand. 3. The Dutch phyficians feem to have been fomewhat at a lofs to account for the health enjoyed by the infant during the firft year. But the full i$ OBSERVATIONS ON THE full expanfion of the lungs is not neceffary to life or health in early infancy, during which, for a fhorter or longer period in different fubjects, part of the blood paffes through the foramen ovale and arterious duct, and is therefore not fully oxygenated *. Dr. Sandifort is doubtlefs right in con- cluding, that the ftructure was connate ; no rupture of the heart could have pro- duced it. His information that the child fcarce cried, never coughed, and was ex- tremely quiet during the firft year, deferves notice. 4. From what has been faid above, the peculiar laffitude felt on very high mountains, and defcribed by M. Sauffure -f from * Hence, probably, the fublivid infantile complexion, Which difappears at various ages, juft as the remains of the fostal circulation ceafe, and is perfectly diftincT from the occafional jaundice of infants. f * Les forces mufculaires s'epuifent avec une extreme * promptitude.—Ce qui diftingue & cara&erife le genre « de fatigue que Ton eprouve a ces grandes hauteurs, *" c'eft un epuifement total, une impuiiTance abfolue < de continuer fa marche-----On ne feroit pas a la lettre < quatre pas de plus, fut-ce pour eviter le danger le 4 plus SCURVY, OBESITY, &c. 7$ from his own fenfations, may perhaps be fatisfactorily explained. In this fituation fatigue * plus eminent.-----Si l'on perfifte a faire des efforts, on 1 eft faifi par des palpitations & par des battemens fi j ' rapides & fi forts, dans toutes les arteres, que Ton f tomberpit en defaillance •, fi on l'augmentoit encore « en continuant de montcr. * La feule ceflation de mouvement, dans trois ou qua- « tre minutes, femble reftaurer fi parfaitement les forces, « qu'en fe remettant en marche, on eft perfuade qu'on « montera tout d'une haleine, jufques a la cime de la < montagne. Or dans la plaine une fatigue auffi grande 1 ne fe diffipe point avec une telle facilite. Mr. f Pi&et fe trouve tonjours faifi d'une efpece d'angoifle c (anxiety), d'un leger mal de cceur, & d'un degout 1 abfolu, defqu'il eft arrive a la hauteur, d'environ 1400 * toifes au defTus de la mer.' (SaulTure Voyages, 4to. I. 482, &c.) The profound fleep (affoupijfement, fommeil prefque lethargique) feems exactly the afphyxia arifmg from an improper air. The laffitude is only the firft degree of this afphyxia. The anxiety, palpitations, Sec. are all kindred fymptoms, and what almoft demonftrates that they are here imputed to the right caufe is a fubfequent obfervation of Mr. SaulTure, who tells us, that on the Col de Geant, at 1763 toifes above the level of the fea, « De charbon ne bruloit que d'une maniere languifTante, So OBSERVATIONS ON THE fatigue very fuddenly comes on, and as fuddenly goes off on .reft. Now in amend- ing thefe rugged heights, the mufcular ex- ertion rnuft expend a great deal of oxy- gene, which the rarified atmofphere will fupply but fcantily. Hence the neceflity of fufpending the fevere exercife to collect a flock of this principle, and hence we fee why it. is fo foon exhaufted. The other ac- « & a force d'etre anitae per le foufHet.' (Jounu de Phtf. Sept. 1788,p. 209) Among the defiderata in medicine, few are, I think, moFe felt than greater choice in the means of procuring fleep. Opium, and other diffufible ftimuli, in fome cafes, increafe the refHeflhefs; and in moft cafes it would be better to induce deep by the abftra&ion of ftimuli, thnn by exhaufting the excitability. Upon this principle we could not have a better foporific than an atmofphere with a drrnimihed proportion of oxygene air: ordi- nary air might be admitted, when the patient was ones laid afleep. Mr. SaulTure repeatedly mentions the very found deep he enjoyed during the nights he fpent in the high fituation above mentioned. The cold of which people traverfing great heights complain, I partly afcribe to the want of oxygene to fupport animal heat. From the narratives I cellect that the fenfible eold is greater than the thermornetrfcar. 1 cident SCURVY, OBESITY, &c. $t cidents of refpiration, which have been as- cribed to i lofs of equilibrium between the external and internal air, probably depend upon the fame caufe. Mr. Plantade, at the age of feventy, fuddenly and placidly expired, befide his quadrant, upon the heights of the Pyrenees. Had he been opened, the left cavities of the heart would, I fuppofe, have been found turgid with blood, and, had he been carefully obferved, his countenance would have fhewn figns of ftrangulation. He died, in fhort, I conceive, nearly as he would have done in the exhaufted receiver of an air-pump, with this difference, that the preceding fatigue had confumed the irrita- bility of his mufcles. Young animals bear the abftraction of ftimuli better than old ones; and there is, probably, a certain mix- ture of oxygene and azotic airs that would be fatal to old, but not to young perfons. The experiments of Mr. Sauffure, Pini, and Reboul, concur in fhewing, that, inde- pendently of its rarefaction, the atmofphere of very elevated mountains contains a far M fmaller 82 OBSERVATIONS ON THE finaller porportion of oxygene than that of the lower regions, efpecially than that of the high vallies of the Alps. 7. Therefore the inhabitants of thefe great elevations, if there were any, ought, ac- cording to the theory laid down above, to be peculiarly fubject to the fcurvy. But as no perfons pafs their lives in fuch fitu- ations, we cannot expect from this quarter any decifive facts one way or the other. Neverthelefs, the only inftance I know of a number of perfons continuing long in thofe inhofpitable regions, does actually fupply a probability in favour of this doctrine. Mr. Condamine, during the ope- rations of the French academicians, upon the fummit of Pichincha, was attacked with fcorbutic fymptoms*. (*) Un de'entre nous (Mr. D'Arcet fays Mr. Con- damine is meant) commenca a reflenter des affections icorbutiques, les Indiens et les autres domeftiques que eu rent des tranchees violentes; ils rendirent du fang. (B.ouguer, Mem. de 1'Acad. R. des Sciences, 174^ The SCURVY, OBESITY, &c. 83 The advantage to be derived from a bet- ter knowledge of the fcurvy is, as in other cafes, to increafe our power of preventing and curing it. And here a thoufand pro- jects prefent themfelves. 1. The neceffity of keeping fhips fup- plied with frefh air becomes ftrikingly ob- vious. And it would be worthy of ano- ther Lind to prove the truth of the theory, by fupplying his patients with air contain- ing a more than ordinary proportion of oxy- gene, which, however, to be done fafely, muft be cautioufly attempted. I was defirous to know whether the tem- perature of fcorbutic patients differed from the common flandard, but I find no obfer- vation of this fort upon record. 2. We muft build our hopes of preven- tion, and more efpecially of cure, upon the acids. The efficacy of the native acids of vegetables is fo ftrongly attefted by different writers down to the moft recent, as Mr. m 2 Drinkwater 84 OBSERVATIONS ON THE Drinkwater (Siege of Gibraltar) and Dr. Trotter, that if an adequate fupply could be provided and preferved, no other means would be requifite for the prefervation of foldiers and failors, whether only liable to the fcurvy, or really attacked by it. A full trial of the mineral acids, as they are called, efpecially the nitric and vi- triolic, ought, 1 think, to be made. The vi- triolic elixir, the worft poffible form has never, even in the opinion of Pringle (1. c. 383.) been properly adminiftered. Water, to which a fmall quantity of the acid fhould be added, would obvioufly be the beft form. Had thefe obfervations been printed before thofe of Dr. Trotter, I fhould confidently have faid, that the vitriolic acid is decom- pounded in the ftomach and bowels, and that the ufe of the nitric acid, as appears alfo from experience to be the cafe with the oxygenated marine acid, would require great caution, left in confequence of its eafy decompofition it fhould inflame the ftomach. I read with no fmall furprize in his SCURVY", OBESITY, &c. 85 his work (p. 147), that the nitric and ful- phuric acids, 4 in whatever matter they are 4 exhibited, pafs through the body pure 4 and unaltered, as when taken, into the 4 ftomach.' He repeats the fame affertion (p. 184.) with refpect to the fulphuric acid. It is however certain, that almoft all animal and vegetable fubftances decom- pound thefe acids; and, in truth, Dr. Trotter has completely mifunderftood the table in the Methodede Nomenclature Chimique, upon which alone he founds his opinion. In this table he fays, * are to be found thofe 4 bodies, of which oxygene is a compound? (he means a conftituent part) 4 arranged ac- 4 cording to the degrees of elective attrac- 4 tion. At the top of the column is water, ' next follows nitric acid, carbonic acid, 4 fulphuric acid, &c. and not till after the 4 tartarous acid come the oxalic, gallic, 4 citric, and malic acids; hence thefe acids, 4 by being more eafily decompofed, or their 4 radicals and the oxygene being confined 4 in weaker degrees of attraction, they are 4 acted upon by the powers of affimilation 4 and 86 OBSERVATIONS ON THE 4 and digeftion of the human body; by 1 which means they become fubjected to 4 the animal procefs, and form new com- 4 binations with our fluids.' The latter part of this paffage feems to confift of mere words; at leaft, the ideas are vague ; and it is certain, that the French philofophers have exhibited only a view of their new names in the column in queftion, and not the com- parative attractions of different bafes for oxy- gene, otherwife the acids muft have flood in a very different order. My opinion of the decompofition of vitriolic acid in the alimentary canal is founded upon the anfwer to queftions afked with a view to afcertain this very fact. Perfons taking vitriolic acid I have found to be very fenfible of the fmell of fulphur upon different oc- cafions. Either therefore vitriolic acid ought to be efficacious, or fome clear and fatisfa&ory reafon ought to be affigned for its want of power. The fame obfervation I think ap- plicable alfo to vinegar. Some obfervations in SCURVY, OBESITY, &c. 87 in Lind feem to favour this expectation, as where he fays, that 4 the relief obtained 4 by bathing the legs * frequently in a day, 4 with warm vinegar, is both quick andfur- 4 prifing? Did he make a comparative ex- periment with warm water ? If herpetic eruptions, * as there is fome reafon to fuppofe, depend upon an abftrac- tion of oxygene, lefs than that which occa- fions the fcurvy, or rather perhaps upon a local deficiency of this principle, one may prefume, that vitriolic acid, the bell re- medy we poffefs for the former, will not be inefficacious in the latter complaint. And although I am not led, by the improper ap- plication of a common name to confound two difeafes clearly diftinguifhed by their fymptoms, yet it may, perhaps, without ab- furdity, be profpofed as a query, whether * The only cricumftance I cannot reconcile to this fuppofition is the efficacy of cantharides in thefe eruptions. The efficacy of certain metallic oxids, ap- plied externally, favours it extremely. 8S OBSERVATIONS ON THE they do not approach each other by a num- ber of intermediate gradations. To illus- trate my meaning, as well as to counte- nance my queftion, I fhall produce an ex- ample of a difeafe, which may, I think, be termed the fcorbutic leprofy, or herpes; between which difeafes again there feems to me no certain boundary. Dr. Pallas ob- ferved this fcorbutic leprofy in more than one place in the Ruffian dominions. It makes a much flower progrefs than the fcur- vy. Thofe whom it affects are not fenfible, during the firft and fecond year, of any con- fiderable pain or weaknefs. The counte- nance appears livid, as if they were ftran- gled; livid fpots, little elevated, and giving no pain, are feen in different parts of the bodv; an herpetic eruption breaks out on the chin; the fpots gradually enlarge, and violent pains are felt in the limbs; the herpetic eruption at laft overfpreads almoft the whole of the body, and to the bare, dark red fpots fucceeds a fcurf, con- fining of long fcales, among which ulcere 4 . frequently SCURVY, OBESITY, &c. §9 frequently break out. Sometimes the fcurf falls off, and the fkin takes on a natural appearance. If a perfon happens to wound or bruife any affected part, foul* fpreading ulcers appear, and often eat down to the bone. The fingers are particularly liable to fuch ulcers, and they commonly fall off joint by joint. This loathfome diftemper except in its very laft flage, does not pro- duce much emaciation or debility. The animal functions go on well. (Pallas, Reife, 302, 303.) The Tartars hold this, which they call, from the complexion of the pa- tients, the black difeafe, to be infectious; yet the phyfician, who defcribes it, faw a family, were the elder brother was firft feized, the younger three years afterwards, the mother a year after him, while the wives of the two brothers, who had con- ftantly lived with their hufbands, continued perfectly free. This obfervation will per- haps appear decifive againft the opinion of thefe poor people, efpecially when we reflect how rapidly the logic of terror, among the ignorant in particular, haftens to conclude, n that 90 OBSERVATIONS ON THE that fuch and fuch diforders are catching. Dr. Paljas mentions a particular, in which this diforder of the Coffacks differs from the leprofy ; the affinity however is ftrik- ing. Thefe Tartars are utter ftrangers to agri- culture. They inhabit a country, where the foil is impregnated with fait, and abounding in fait lakes. Their diet is fifh, often falted when it is more than half pu- trid. About the fort Jaifkoi Gorodoc alone, watery j fruits, as melons, and the mofil in- difpenfable kinds of garden herbs, are cultivat- ed, but not by the Coffacks, who muft buy, if they will have them, and who, therefore, I fuppofe, fupply themfelves, but fcantily. 3. SooiNS,an acidulous preparation of oatmeal, by which, asPringle informs us (1. c. p. 382.), one of captain Cook's moft intelligent friends cured his fcorbutic fick on board, deferves more attention than it has obtained. It is prepared by pouring hpt SCURVY, OBESITY, &c. 91 hot water upon oatmeal, and fuffering it to fland till it has become fourifh. The de- canted water is to be boiled down to the confiftence of a jelly. The efficacy of this fermented acid affords a prefumption in fa- vour of vinegar ; and it may, 1 fuppofe, be generally procured on fhip board. 4. Nitre feems to deferve attention in the cure of fcurvy. It is doubtlefs de- compounded in the primes via, and capable of fupplying much oxygene. Thefe fatal confequences, which have fometimes fol- lowed exceffive dofes of nitre, have been, I imagine, owing to an inflammation of the ftomach, occafioned by the oxygene; and it is, probably, upon the direct or indirect action of oxygene, that the danger of expofing wounds and certain parts of the body de- pends. 5. Sweet wort, or the extract of malt, I conceive, from its chemical compofition, to have fome, though inferior, antifcorburic virtues. And the great authority of captain N 2 Cook, )2 OBSERVATIONS ON THE Cook, who calls it one of the beji antifcorbu- tics yet found out, of Mr. Patten his fur- geon, and others, ftrengthens the opinion which chemiftry fuggefts. It is true, as Dr. Trotter obferves, that Macbride's theory is indefenfible; it is true alfo, that had there been nothing erroneous in his theory, wort, the unfermented and unfermenting extract of malt, could have had no efficacy in fcurvy ; neither has it been of late pretended that wort will of itfelf completely cure the fcurvy ; but from the confiderable proportion of oxygene contained in fugar, it is probable that it will retard the approach, and check the ravages of the difeafe. Dr. Trotter, I conceive, has much too lightly pronounced, that * the fimple wort paffes 4 eafily through the body, and that it un- 4 dergoes no decompofition in the ftomach.' And, admitting this, does he fuppofethat none is abforbed ? that it tranfmitted no oxygene to the fyftem of thofe hundred and thirty fcorbutic patients, who took it for fourteen days, without a fingle inftance 4 of ficknefs, 1 gripes, or purging,' occurring (Lind, P- 5390 SCURVY, OBESITY, &c. 93 P- 539') anc^ who, though they were not cured by the wort, appear, as one may fairly conclude from Lind's expreflions, to have grown better while they were taking it ? It would, I think, be rafh and unjuftifiable in the higheft degree to lay afide a prepara- tion, at once cheap, eafy, and palatable, and which appears to poffefs, in whatever light it is confidered, powers of prevention by no means defpicable. I am inclined to think much the fame of four krout, notwithftand- ing Dr. Trotter's objections.—The relation between a diet of faked provifions and the fcurvy, it is not eafy to determine with pre- cifion. Such a diet is certainly not necef- fary to the production of fcurvy ; the facts already enumerated afford abundant evi- dence of the falfehood of this hypothefis, and it has, of late, been generally aban- doned. Neverthelefs, faked meat may be capable of giving rife to the difeafe, either by itfelf deftroying loofe combination in which oxygene feems to be held by hydro- gene and azote in the recent fibrous and cellular fubftance of organic beings, or by fuffering 94 OBSERVATIONS fuffering a combination to be deftroyed, in which perhaps oxygene is not a great deal more firmly held than by the azote of the atmofphere. The diet, therefore, of befieged garri- fonswill, perhaps, account for the produc- tion of the fcurvy, though the foldiers may not breathe the pureft air in their barracks. Prifoners, efpecially thofe taken in war, are frequently attacked by this difeafe; and if we recollect how confi- derable their numbers have fometimes been, and how clofe their confinement, we fhall be at no lofs to underftand why they fhould be vifited by this dreadful cala- lamity. One obfervation on the means of preven- tion and cure I will add before I quit the fubject of fcurvy. Of all the fubftances that can at once be cheaply procured and long preferved, the concrete acid of tartar feems by far the moft promifing ; it is very grate- ful, and comes near to the citric acid. THIS ON OBESITY. 95 THIS theory of fcurvy feems, with fome modification, capable of being applied to the accumulation, or, more properly fpeak- ing, the fecretion of fat in excefs. The oily parts of animals, I believe, principally differ from the reft of the heterogeneous mafs, commonly called flefh, in a fingle cir- cumftance; they appear to contain a final- ler proportion of oxygene. The actual con- vertibility of the fofter folids into a fub- ftance like fpermaceti, is a clear proof of the affinity between mufcle, cellular fub- flance, and fat, as to their compofition; add or take away a little of one or more of their conftituent parts, and the alteration is ef- fected. The converfion, as one may, I think, infer from the obfervations made in the burying ground of the Holy Innocents at Paris *, depends on fome very flight caufe. The * In the large common graves, where feveral hundred bodies lie together, all the foft parts were wonder- fully 96 OBSERVATIONS The diftillation of organic matter, vio- lent as that operation is, favours the fuppo- fition, fully changed j in fome fubje&s, where the procefs of ccnverfion was not finifhed, a few of the mufcular fibres were vifible; in the reft, all the mufcles, even the heart, the membranes, tendons, and vifcera had disap- peared ; the brain was alfo changed. The fubftance, into which all was alike changed, was foft, ducTile, greyifh white, much refembling new cheefe. It frothed ex- tremely with water, and proved to be an ammoniacal foap, from which acids feparated a concrete oil, which when dried (lowly, was like fpermaceti, having a lameh lated, cryftalline texture ; it was much more foluble in alcohol than fpermaceti is, and it readily difiblvad in cold ammoniac. As it bore fome refemblance to wax, Mr. Fourcroy propofes to call it matiire adipo-cir- eure,— The foap or gras is faid, however, not to confti- tute above T^ or A of the body. The reft evaporates in the form of water, carbonic acid air, and perhaps fome unknown elaftic fluids. (Annal. de Chimie, v. 154. viii. 17.) Mr. Thou ret appears to entertain fome doubt as lo the converfion. He fays they appear to be converted, but imagines the converfion may not be real. H~ feems to be perplexed by fome mdiffinct hypothefis lurking in his mind, and perhaps is not aware that converfion can only mean a change from the lofs or acceffion of fome conftituent part. Except the bones, the colcur- ing matter of the bile, of the bronchial glands, the pig- 4 mentum ON OBESITY, 97 fition. The water and carbonic acid, hav- ing appropriated the oxygene to themfelves, the oils, ammoniac, and carbone appear to be formed from the refiduary azote and carbone. From Mr. Fourcroy's experi- ments, as well as from the procefs of diftil- lation, it looks as if the production of ani- mal oil and ammoniac were operations nearly allied. One would not affuredly reafon with much confidence from diftil- lation to fecretion, efpecially as the diftilled mentum nigrum, < and, perhaps, the proper fubftance of ' the mufcles, this transformation has entirely fubdued c all the other parts •, the lkin, adipofe fubftance, mem- * branes, mufcles, vifcera, cartilages, glands, tendons, ' aponeurofes, and even the fluids.' Again—' though ' the transformation feems to have taken place in the 4 mufcles, it has probably eftabliihed itfelf in them by « means of the lymphatic and unctuous juices.' (J. de Phyfique, April 1791, p. 256^—7.) Mr. Halle, in treating the fibrous parts of animals with nitric acid (ibid. Mai, p. 338—9.) obtained an oily concrete, fimilar to fpermaceti, and unalterable by nitric acid. If, as Mr. T. feems to argue, this were really the bafe of the animal fibre, it might eafily happen that during a certain ftate ©f the fyftem it fhould be changed into fat inftead of mufcular fibre. q differ 9S OBSERVATIONS differ in appearance from the fecreted oils, and doubtlefs alfo, fomewhat in the propor- tion of their conftituent parts. But is it unlikely that, if the blood itfelf fhould ever contain but little oxygene, a fubftance con- taining a fmaller proportion of oxygene than other animal fubftances, fhould be formed ? and if mufcle, membrane, tendon be changed into fat after death, why may not the powers of life, inftead of mufcular atomss occafion- aily combine into fat thofe elements, which, under other circumftances would have gone towards the formation of fibres or laminae ? In diffection we avoid fat fubjects, when we defire to fhew the mufcles diftinctly. Is it that there is lefs mufcle as there is more fat ? or are the fibres, the mafs of mufcle remaining the fame, only rendered more indiftinct? Every new hypothefis, if it be but thought worth the trouble of refuting, adds to our flock of well-afcertained facts. Till it be certainly decided, whether, as I fufpect, the fat encreafes at the expence of the mufcle, let us try if we cannot difcover, in the living fyftem itfelf, fome obvious ap- pearances, ON OB E S'lf V. '99 -pearances, indicating a tendency to form fat, whenever there is a deficiency of oxygene to a certain degree. i. Among the Africans, of whofe fuf- ■ ferings on board the; flave fhip Dr, Trotter has given fo particular and affecting an hif- -tory, corpulence feems to have been, as it were the firft ftage of fcurvy. 4 When a 4 negro was becoming rapidly fait,' fays he, 4 it was no difficult matter to determine 4 how foon he would be feized with the 4 fcurvy;' fo that corpulence feems here to have been the harbinger of the fcurvy. Writers have been particular in noticing that this difeafe feldom or -never produces emaciation. Dr. Trotter, upon whofe in- formation we may place full reliance, tells us, that having purpofely enquired among his medical acquaintance in the navy, he did not find one who confidered the wafting of the flefh or abforption of fat as a fynip- torn 4 congenial to fcurvy.' He immedi- ately fubjoins fome obfervations of his own, that' clearly indicate a connection between o 2 the I Si OBSERVATIONS the fcurvy and obefity (p. 98, 99.) 'In 4 a corpulent ftate of the body,' he fays, 4 the moft hideous features of the difeafe 4 are expreffed; fuch are the bloated looks ' and countenance, &c.' In a mefs of jnjdfhipmen, who lived altogether on the fhip's fare, the only one he ever faw affected with the fcurvy was 4 a young man remark- 4 ably corpulent.' From the whole of his obfervations it appears clearly that obefity pre-difpofed his patients to fcurvy, or rather was to them what cachexy is to dropfy. %, The emaciation produced by acids, which is exceflive, where they are taken to excefs, is a fact of which it is only necef- fary to remind the reader. In cyder coun- tries the people are habitually leaner than where beer is the common liquor. 3. That inactivity which ftands to obefity in the relation both of caufe and effect, ge- nerally prevents fat perfons from attempting to reduce themfelves ; and though they may make a few ftruggles a firft, they finally fubmit ON OBESITY. io» fiibmit to the incumbrance. They feldom confider themfelves as in a ftate of difeafe, and a prejudice prevails, that corpulence cannot be cured without danger. Hence we hear but little of the medical treat- ment of obefity. The authentic facts, how- ever, which we poffefs, fhew that it may be fuccefsfully treated in the fame manner as the fcurvy. This analogy is particu- larly ftriking in two cafes of unwieldy cor- pulence, which Fothergill removed by a ftrict vegetable diet. Mr. Wood, whofe cafe is fo well known from his own account publifhed in the Medical Tranfactions, is another inftance of the fame kind. 4. Short-winded perfons are very often corpulent, and even many afthmatics. Wherever the livid colour * of the counts nance * I mean an occafional or prevailing hue, not a per- manently fixed ftain, fuch as the red nofe and cheeks of perfons poifoned by fermented liquors exhibit. This deformity I fufpecl: to arife from inflamed lympha- tics, which, by continued excefs in drinking, become in- durated. When a red nofe alternates, as it often does, with pain in the Tver, are the abiorbents only or the --. whole 102 0 B S-E R V A T I 0 N S nance indicates a deficiency of oxygene, there you will feldom fail to obferve a full habit. Here I fhall probably be told that I put the effect for the caufe, fince dyfpncea is the confequence of the accu- mulation of fat. Inftances may- alfo be produced of an emaciated habit of body,. attended by difficulty of refpiration. In anfwer to the firft objection one would not affert any thing pofitive; it is a fubject on wtiich it is not eafy to make de- cifive obfervations. It only appears to me, from my remarks on corpulent habits, that dyfpncea and obefity favour each other, that I think it evident alfo that every different fpecies of dyfpncea, though in appearance whole organized fubftance alike affected ? My reafon for fufpecting the lymphatics to be principally affected is not only becaufe the career of grofs debauchery fo frequently terminates in dropfy, but becaufe I have been able to feel cords like fcirrhous abforbents in va- rious parts of the bodies of perfons deftroyed by al- cohol. Had fo much induration been owing to fcirrhofity, lancinating pains muft have been felt, which I have been aflured by the patients was not the cafe : nor was there any caufe whatever befides thefe cords for fufpetting the prefenceof fcirrhus or the approach to cancer. equally ON'OBESIT Y; 103 equally diftreffing to the patient, does not equally prevent the action of the air and the blood on each other. It is not fo difficult to elude the force of the other objection. The living body is doubtlefs fubject to the influence of coun- teracting caufes, of which that which tends to diminifh the fat may prevail over its an- tagonift. Fat may be fecreted without being accumulated. In a perfect theory, thefe counteracting caufes, I am fenfible, ought to be fpecified, and their power efti- rnated; but wre are fo far from having at- tained fuch precifion in the knowledge of any one of thofe various chemical opera- tions that are comprehended under the im- proper term fecretion, that it is making fome advance to indicate a probable general caufe, even if we are obliged to leave its action to be accurately determined hereafter. I object to the term fecretion, taken in its proper fenfe, becaufe many circumftances concur to render it probable, that only the ele- ments of fecreted fubftances exift in the blood, and that combination is the office of the io* OBSERVATIONS the fecretory organs. No one now, I fup- pofe, will maintain that they are mere filtres. 5. The mechanical effect of exercife has never yet been fully appreciated. I have no thought of difturbing the abforbents in the poffeffion of their claims; their action is, 1 doubt not, increafed by exercife. But may not exercife alfo, by introducing more oxygene into the fyftem*, and by diffufing it more widely, check the formation of a fubftance containing little oxygene, while the fat, in common with the other fluids and folids, is abforbed ? In the courfe of life there are two periods during which the fat is apt to accumulate ; the firft is * A very delicate obfervation made by Mayow is well deferving of notice in eftimating the effect of ex- ercife. A dog that was panting and breathing deeply, on receiving arterial blood into one of his veins, in- ftantly began to breathe fo calmly that his refpiration was fcarcely fenfible. The animal received from an un- ufual fource the fubftance which is probably expended in mufcular action; it was therefore no longer neceffary to inhale it rapid'ly. 2 that O N O B E S I T Y. Io5 that of infancy, during which not inaction merely, but, if I am not deceived, the ftate of the blood alfo, favours the formation in excefs as well as the accumulation of fat. The lungs are not probably fully expanded for a confiderable time after birth ; and whatever quantity of blood goes to the aorta by the arterious duct, or to the left auricle by the foramen ovale, which fre- quently continues open for a confiderable time, muft fo far prevent the oxygenation of the fyftem*. The commencement of the feeond is fixed by Haller at forty years of age. At this period of life an indolent difpofition is coming on ; neither curiofity nor the other paffions any longer agitate us with equal force. At this period I conjecture that there is alfo a deficiency of oxygene in the fyftem ; and the conjecture will receive * Cascum duBum arteriofum reperi aliquando pott paucos menfes, alias ferius, ut fecundo anno abfoluto tu- bnlus pervius fuerit, Hallcr. III. 161. celerius adeo quam foramen ovale clauditur, ib. 162. V, fome loS OBSERVATIONS fome confirmation from the papers of Dr Girtanner; whether it be that the ftomach and lungs are fo altered as not to imbibe it in the ufual quantity, or the other con- ftituent parts of the folids and fluids are fo altered in their proportion as to have loft fomewhat of their attraction for oxygene, or upon whatever elfe it may depend;, The leffened vigour of the whole fyftem, the diminiihed irritability of the mufcular fibre, the wearinefs that now fo much fooner fol- lows exertion, indicate this, and the rigidity of the tendons, fibres, and laminae may, in advanced age, be owing to a permanent, as, in fcurvy to a temporary, deficiency of the fame principle. If this fuppofition were juft, might not fome means be difcovered to protract the period of youth and vigour indefinitely.—Whether true or falfe, and even though we fhould never be able to re- ilore new excitability to the fyftem, there can be no doubt of the immediate prac- ticability of prolonging life confiderably, and, what, is much more definable, of maintain^ ing a firmer ftate of health, by a proper management ON OBESITY. management of the excitability during the periods of infancy and youth. 6. It is generally obferved that perfons who indulge much in fleep are apt to grow fat. From the well-known infrequency of refpiration during fleep, a finaller quantity of air muft be taken into the lungs than while we are awake. The neceffary con- fequence and its application are obvious. The zoologifts fupply obfervations to the fame purpofe. Thus, Mures montani hieme pinguiffimi hunt, etiam abfique cibo*; idem- que de urfis eft notiffimum -f; ut rette pin- guefcant gallinte, plurimum ut dormiant neceffe * HallerElem. Phyfiol. I. 39. For this fact he quotes Ray's Wifdom of God, but, as I remember, erro- neoufly. Ray, if I do not miftake, fays, that the mar- mot, the mus montanus here underftood, is fat in au- tumn, and comes out lean in fpring, juft the contrary of what Haller makes him fay. I do not therefore build upon what he afTerts of the marmot or the bear: the ether facts are to my purpofe. f Ariftot. Hift. Anim. VI. 36. Hillerftroem Iam- telands Diur. fang. P a eft, ■ioS OBSERVATIONS eft *, eoque fcopo ipfum lolium in cibum mifcetur -f. Vegetables doubtlefs decompound water; it appears almoft certain that they muft com- bine the hydrogene with azote abforbed from the atmofphere, to which a certain portion of oxygene is added. How then comes it to pafs that thefe elements are not at times fo combined as to produce an excefs of oil and a fort of obefity in the vegetables ? fome fuch modification of their functions does really take place. In proportion as they are more expofed to heat and light, they feem to form a larger quantity of oils and refins, as well as of faccharine matter, which is nearly allied in its compofition to the two former fubftances. Wlierever they are able to decompound moft water, there alfo they will probably abforb moft azotic air. Muft not thefe two functions go on moft * Reaumur, Art de faire eclorre des oifeaux domefti- ques, p. 2. id. 2. p. 392. t Id. p. 393- vigoroufly ON OBESITY, i^ vigoroufly in thofe plants, which in the fame foil and climate form moft oil ? We know befides, that vegetables are ca- pable of forming oils, either exactly the fame as thofe of animals, or very nearly re- fembling them. Thus we have the fuet of the croton febiferum, the butter of the phtsnix dattylifera and of the butyrum cacao. When from a more intimate acquaintance with them, we fhall be better able to apply the laws of organic bodies to the accommoda- tion as well as the prefervation of life, may we not, by regulating the vegetable functions, teach our woods and hedges to fupply us with butter and tallow ? Thus our paftures arid meadows, the moft fertile fpots in every country, would, many of them, be gained to the cultivation of corn, the immediate food of man. And how many millions of in- habitants more might Britain maintain, if we could feed upon the immediate pro- duce of the foil ? how many tons of vege- table food' are condenfed into every fat ox ? WHEN; no OBSERVATIONS WHEN the medical practitioner finds him- felf deferted, in every emergency, by the hy- pothefes of the fchools, he is too apt to at- tach himfelf to a blind routine, and to con- clude that attempts to explain the capri- cious phsenomena of difeafes, for fo they muft appear to him, will be hereafter as fruitlefs as they have heretofore been. The next ftep is to decry the value of that which he neither poffeffes nor hopes to at- tain ; nor will he tolerate in others attempts to difcover the laws of animal nature, of the exiftence of which it is yet impoffible to doubt. Perfeverance in the obferva- tion and comparifon of phsenomena, which have hitherto been obferved and com- pared in vain, is the privilege of a few fuperior minds. Examples of ill fuccefs in thefe difficult inveftigations do not overpower their firm perfuafion of the ex- iftence of invariable laws, and of the pof- fibility of a complete theory of difeafes. I feel not much reverence for thofe who pique ON CONSUMPTION. in pique themfelves upon pure experience. ' There are few difeafes in which we have any fixed rule of practice; and our fpecifics are fo few, and fo eafily applied, that this part of medicine may be acquired without difficulty or lofs of time. In moft inftances a theoretical deliberation of fome fort muft precede prefcription, and here the difcrimi- nation of perfons habituated to fpeculation will have the fuperiority of fkill over chance, and their fertility of refources will appear to peculiar advantage. In the confumption of the lungs, as in- deed in too many other difeafes, a conjec- ture may be offered with the lefs diffidence, fince experience cannot here fet up the flighteft pretenfion to overawe fpeculation. This melancholy truth will, I hope, propi- tiate thofe whofe difpleafure might other- wife arife againft an attempt to difturb medi- cine by the introduction of new ideas. I beg- leave alfo to affure perfons little acquainted with the recent progrefs of fcience, that I do not employ the French chemical nomen- clature 112. OBSERVATIONS clature from affectation ; but as the French* kas prevailed over the old theory of chemif- try, fo I expect that the terms fanctioned by the founders of that theory, however un- couth they may found at prefent, will finally eftablifh themfelves, partly as being more convenient, partly as being the language in which the moft eminent phiiofephfirs of Europe communicate their difeoveries. Perfons acquainted with the fubftances they deftgn will find no obfeurity in the terms, and for others it is indifferent what terms are ufed. Not much feems to he gained by ranking the phthifical tumours and ulcers of the lungs- among ferophulous complaints. We have no very fuccefsful method of treating fero- phulous fores, wherever fituated; neither have we any tolerably clear idea of the na- ture of the difeafe. Not to mention that very different ailments are comprehended under a term fo conveniently vague. I fee no hopes therefore of transferring any use- ful ideas from the external appearance of - fcrophuh ON CONSUMPTION. n< fcfophula to the internal form of the dif- eafe, if they fhould be effentially the fame, of which I am by no means fatisfied. We fee, it is true, ftrunlous perfons attacked by confumption; but we may obferve many others attacked by it, who have had no glandular fwellings, or other marks of fcro- phula. However this may be, the only circumftance in phthifis, from which, in our prefent ftate of ignorance, we can hope to reafon to any purpofe, has always ap- peared to me to be the occafional effect at leaf! of pregnancy in fufpending the pro- grefs of phthifis; for if we could once difcover how pregnancy produces this lin- gular effect, we might be led to difcover alfo a method of fupefinducing and pro- longing the fame change of the fyftem at pleafure. I had repeatedly attempted to proceed through the obfcurity by the help of this clue, but in vain. I have lately had a very favourable opportunity of obferving this ef~ £ect of pregnancy, but could fix ©n no plau- o fible ri4 OBSERVATIONS fibie fuppofition, with which I might com- pare the phenomena. At laft, when it was too late, the difeafe having returned and de- ftroyed the patient, the following fuppofition occurred: The foetus has its blood oxy- genated by the blood of the mother through the placenta. During pregnancy there feems to be no provifion for the reception of ■ an unufual quantity of oxygene. On the contrary, in confequence of the impeded action of the diaphragm, lefs and lefs fhould be continually taken in by the lungs. If therefore a fomewhat diminifhed proportion of oxygene be the effect of pregnancy, may not this be the way in which it arrefts the progrefs of phthifis; and if fo, is there not an excefs of oxygene in the fyftem of con- fumptive perfons ? and may we not, by pur- fuing this IJea, difcover a cure for this fatal diforder ? I am not able to prove the exiftence of this phlogiflicated or putrefcent ftate of the fyftem, as it would formerly have been called, rniring pregnancy. I muft therefore appeal ON CONSUMPTION. 115 appeal to the prefent knowledge or future obfervation of accoucheurs to determine whether it manifefts itfelf in the colour of the blood, bleeding of the gums, dark co- loured fpots, vibices, or any other fcorbutic fymptoms. The ftate of the blood in preg- nancy is certainly peculiar; this the wri- ters on midwifery declare in very pointed terms ; but I have not found its fenfible qualities fo well defined as might be wilhed. Thus we read that4 the blood of pregnant 4 women is always found to have what is 4 called a fizy appearance, though of a pe- c culiar kind, and evidently very different * from that which is obferved in cafes of in- 4 flammation *.' I know not whether the fpots or blotches mentioned by the fame author-)-, or the red fpots J mentioned by Mauriceau as covering the legs and thighs, or the dark colour of the abdomen and inferior extre- mities defcribed by Camper in his difcourfe on the colour of the negroes, as often {&cn '* Denman, Introd. to Midwifery, p. 248. ; p. 266. ± p. 72. 0^3 in nhi. When it attacks perfons who have herpetic eruptions, do thofe eruptions ceafe ?—Is not the chillinefs of fcor- butic patients, and of the blue boy, owing to a want of oxygene? this chillinefs feems prefectly diftinct from febrile horror and rigor.—And is not that fenfe of heat, which fo much diftrefTes phthifical patients, owing to atlual heat, produced by the excefs of oxygene ? 4 the ON CONSUMPTION. 119 4 the canthus of the eyes are alfo redder * than when in health *.' Again, towards the termination of the difeafe, 4 the tongue 4 appears clean, and, with the fauces, is of a 4 bright red\? Here I requeft every rea- der acquainted with the modern doctrine of refpiration (otherwife he is not a proper judge) to paufe a moment. It will, I ima- gine, readily be allowed that if the blood- veffels were filled with more florid blood than ufual, this identical bright rednefs would be feen. The caufe, then, is ade- quate to the effect : t\\e change, too, is not, as in the loofe analogies of the humoral pathology, tranfported from fome remote part of inanimate nature, and at random im- puted to animals. If the various evidence adduced in the cafe of fcurvy fhould not prove fatisfactory, yet the moft determined fceptic will not hefitate to admit in afthma a deficiency of oxygene and a correfponding change of colour. Why then will he not infer from an oppofite change of colour an * Reid's Effay on Phthifis Pulm. ed. 2nd, p. 13. r Ibid. p. 19. oppofite uo OBSERVATIONS oppofite condition of the blood ? If in the* pucr cceruleatus of Dr. Sandifort, the tongue and fauces were deep blue or purple, be- caufe the lungs did not admit oxygene enough, will it not be granted that a bright red indicates the reception of too much r 4 But then the blood itfelf ought, accord- * ing to your fuppofition, to be brighter than 4 ordinary ;' the arterial blood certainly; and a comparifon of the arterial blood of phthi- fical and healthy perfons wrould be fo inte- refting on this very account, that 1 wifh it were practicable. But if we confider the ^ whole action of oxygene upon the blood, we fhall not perhaps expect the difference to he fenfible on a comparifon of the venous blood; for oxygene fometimes darkens and fometimes enlivens the venous blood; not, however, indifcriminately, but under determinate circumftances. When blood is expofed to oxygene air, it firft becomes flo- rid, and afterwards black. Mr. Fourcroy and Mr. Haffenfratz * have afcertained this * Armales de Chimie, t. IX. fact ON CONSUMPTION 121 fact in a very careful manner; and I have had feveral opportunities of remarking the fame change, The oxygene, which at firft is combined with the whole mafs of the blood, or the red globules at leaft, after fome time is attracted by the hydrogene alone or united with azote, and forms accordingly water or carbonic acid. If oxygene be added in a large quantity at once, or loofely combined, the blood is never brightened, but turns immediately black, as when oxy- genated marine acid is added to blood. Probably the folids, during circulation* more than divide with the blood its loofely attached oxygene; if they have a fuperior attraction, they will, as fome of the conftitu- ent parts of the blood itfelf do upon fland- ing, take the whole and leave the blood dark-coloured. Hence then it appears poffible enough that an unufual quantity of oxygene being thrown in through the lungs, the folids might attract it and be confumed them- r felves, t22 OBSERVATIONS felves, or prepare \ for abforption in fome way not underftood, while the venous blood returns to the lungs of its ordinary colour; and, were its colour changed, the difference in the fhade might not be obvious; be- fides, fome of our chemical difcoveries are fo recent, that time has been wanting to apply them to improve medicine extenfively; fo that fatisfactory comparative remarks on the co- lour of the venous blood in comfumptive patients are not to be expected ready made. We feldom perceive much more obvious phsenomena than this probably can be, till we are prompted to look for them. From Willis to Forthergill, and from Fo- thergill downwards, fcarce any real obferva- tion occurs upon the ftate of the blood. One tells us that it is polluted, another that it is contaminated, a third that it is acrid, a fourth that it is putrefcent *, without ever recollecting * Left it fhould be fufpedted that putrefcent is here a found fignificant, it fhould be obferved that «when 1 we examine the blood drawn from patients in every * period of confumption, fo far from any appearance « of ON CONSUMPTION. 123 recollecting that to employ terms expreffive of phenomena, fuch as the fenfes may re- cognize and to reafon upon fuch phaenomena alone, are indifpenfable conditions in phi- lofophizing. Finding fuch little fatisfadion in the wri- ters whom it was in my power to confult, I applied to a gentleman whofe opportuni- ' of diffolution in its contents, the reverfe is conftantly 1 found-, a thick buffy fize and firm craffamentum. < Nay, fo inconfiftent are the favourers of this doctrine' (i. e. of the putrefaction of the fluids and folids in cer- tain difeafes)« that the fize, and the degree of cohefion * in the blood, has always been efteemed an indica- « tion that the operation ought to be repeated, and « much blood has been unneceffarily fhed accordingly. * Nor in its progrefs do we obferve any fymptoms « fimilar to thofe found in difeafes ufually termed pu- c trid ; no petechia, vibices, fordes about the teeth, or blood ' ijfuingfrom the gums, and other parts of the body.' R'eid, p, 7, —2. Dr.-----of Edinburgh, whofe experience ia blood-letting is immenfe, ufed to teach that in phthifis there is an unconquerable morbid tendency in the fyftem to generate blood.—The firm craffamentum, according to Dr. Gr'.canner, is a fure indication of excefs of oxygene.—Little difpofitbn to coagulate in fcor- butic blood—the fame in the blue boys blood: a ftriking co- incidence !—oppofite ftate in phthifis not lefs ftriking. r 2 ties i24 OBSERVATIONS ties of infpecting the blood of phthiiic al patient have been ample, and whofe fine experiments on frigorific mixtures atteft his trJents for obfervation, and will difpofe the public to confide in his accuracy. I afked him limply, without any previous commu- nication, whether he had noticed any par- ticular appearance in the blood of phthifi- cal patients. ' Yes,' he replied, 4 and that 4 fo conftantly, that I believe 1 could ge- 4 nerally diuinguifh blood taken from fuch 4 patients, efpecially where the diforder is 4 confirmed.'-—On the following written an- fwer, he obferved that colours are not eafily defcribed, and, perhaps, his terms might not be the bell chofen : florid and purple feem indeed not well to agree. Dear Sir, IN anfwer to your queftion whether I recollect to have obferved any particiw lar appearance in the blood from phthifi- cal patients, 1 can inform you that 1 have always been as it were involuntarily, and without any particular defign of attending to O N CON SUMPTION. 125 to it, ftruck with its thin confiftence, and its florid purplifh colour.—Upon fince putting ^ the fame queftion to a foreign gentleman, who has paid particular attentionto its ap- pearance, and even made experiments upon it, he replied, that it differed from other blood in being thinner, more florid, and having a purplifh hue. &c. &c. Oxford, 1 Richard Walker. July 25//-', 17920 » This foreign gentleman happened to vifit the Radcliffe Infirmary foon after my con- verfation with Mr. Walker. He has de- duced fome peculiar opinions on the na- ture of phthifis from his refearchcs on the blood taken from perfons labouring under the difeafe: thefe opinions, I underftand, are quite different from that which I have propofed, and indeed utterly foreign to it. It is well known that the fymptoms of phthifis have been greatly agg.avated in fome patients who have been made to re- fpire »26 OBSERVATIONS fpire oxygene air. Mr. Fourcroy defcribes the refult of the trial of oxygene air upon twenty patients, of whom he faw eleven him- felf. After a few flattering appearances, which infpired them with very fanguine hopes, they were all fenfibly the worfe for this treatment, and as fenfibly relieved by aban- doning it. 4 Even amid their felf-congra- ' tulations,' fay s he, 4 feveral figns admo- ' nilhed the attentive phyfician that their * hopes were ill founded. The fkin was ' dry and hot; the face took fire and be- ' came of a mere florid red, s'allumoit etfe • coloroit d'un rouge plus vif quitneioit au- 4 paravant? This heightening of the co- lour by the infpiration of oxygene air de- pofes ftrongly in favour of the opinion I am maintaining. Since the complexion, al- ready more florid than natural, is height- ened by the addition of oxygene, may we not conclude that the firft gradation is alfo owing to an excefs of oxygene. 4 The fymp^ 4 toms' Mr. Fourcroy goes on to inform us, in a fortnight or three weeks after the firft feerningly favourable effect of the oxygene ail? ON CONSUMPTION J27 air 4 became all at once more fevere; the 4 change was indicated by a dry convulfive * cough, fpitting of blood, a fenfation of 4 burning heat and fharp pain in the thorax, a ' fever almoft acute and threatening to be- 4 come inflammatory, by agitations in all 4 the members, reftieffnefs, and thirft. 4 It was neceffary to bleed, to give anti- * phlogiftic and fedative remedies, and the * patients fhewed great unwillingnefs to in- * fpire the oxygene air. When thefe violent 4 and alarming fymptoms were allayed by 4 proper treatment, the difeafe refumed its 4 ordinary form, and the fever appeared with 4 its quotidian type; the expectoration be- 4 come purulent again. In its 4th ftage the 4 difeafe made a quicker progrefs than ufual. * This accelerated progrefs, the fymptoms of 4 inflammation, the uneafinefs, the oppreffion, 4 the burning (ardeur) of the lungs, the ftop- 4 page of the expectoration, the acute hae- 4 moptyfis, all thefe phenomena were ma-^ 4 nifeftly owing to the ufe of oxygene air. 4 They equally took place in eight patients 4 who were not fo far gone as the others; 4 and 128 OBSERVATIONS 4 and it was neceffary to abandon this mode 4 of treatment—the patients themfelves in- 4 deed defired that it might be abandoned *.' In the appendix to one of Dr. Prieftley's volumes on air, fome cafes are mentioned of phthifis, in which the patients were fen- fibly relieved by breathing common air largely mixed with carbonic acid air. Dr. Percival tells us that he has 4 adminiftered 4 fixed air in a confiderable number of cafes 1 of the phthifis pulmonalis, by directing 1 his patients to infpire the fleams of an • effervefcing mixture of chalk and vine- 4 gar, or vinegar and potafh. The hectic 4 fever has been confiderably abated, and • the matter expectorated has become lefs 4 offenfive and better digefted. I have not,' he adds, 4 yet been fo fortunate as to effect * a cure. One phthifical patient has, by 4 a fimilar courfe under Dr. Withering's 4 care, entirely recovered, another was ren- 4 dered much better, and a third, whofe * Annales de Chimie, iv.85. 1 4 cafe ON CONSUMPTION. ug 4 cafe feemed to be truly deplorable, feemed * to be kept alive by it more than two ' months *.' We cannot be furprifed that thefe ex- periments fhould not have been attended with greater fuccefs, if we con fi der that thofe who made them could not at that early period be enlightened by the grateful dawn of a probable theory; that having no well-defined end in view, they could not vary their means with fufficient intelligence; and that, where the apparatus was fo awk- ward, fufticient perfeverance could not well be expected. If our object be to lower the ftandard of the atmofphere, carbonic acid air will not probably be chofen for this pur* pofe. Should it be objected, that the ab- straction of the oxygene was not continued long enough for the effect to be produced in this way, it may be replied, that in Mr. Fourcroy's experiments the application of oxygene was not probably continued much longer. * Prieftley, I. 301. s Some no OBSERVATIONS Some fmall probability arifes in favour of this theory, from the inconfiderable number of failors who die of phthifis, unlefs the com- mon books, as thofe of Lind, Rouppe, Blane, &c. from which alone 1 draw my information, have impreffed me with wrong notions on this point. Seafaring people are particularly expoied to.wet and cold, the exciting caufes of phthifis ; a large proportion of them are, I fuppofe, of fuch an age as, according to the common eilimate, is mort liable to be attacked by confumption, and yet they feem to be even peculiarly exempt from this difeafe. In the ten years' regifter kept by Mr. Gorfuch, at Shrewfbury, upwards of one fourth of the deaths appear under the title, confumption. Though the bills of mor- tality are inaccurate in their denomina- tions, yet their authority is fufficient to prove, that vaft havoc is made by con- fumptions in London, From the accounts and lifts of the fick and dead on ffiip-board, confidered with the neceffary attention to the great difference of circumftances, I flVculd not conceive fo formidable an idea r VI ON CONSUMPTION. i3r of the ravages committed among feafaring perfons by this diforder; before any fafe judgment can be formed, however, it would be neceffary to have more precife data than I have met with, and efpecially to afcer- tain how far it is common for perfons feized with confumptions at fea to die on fhore. Scorbutic perfons ought not, according to this theory, to be liable to phthifis, nor phthifical to fcurvy ; at leaf! it fhould feem, that as one of thefe difeafes comes on, the other fhould retire. It does not appear to' me, that we have well-afcertained facts enough here to afford a teft of the truth or falfehood of the forgoing reafoninp-. Dr. Lind, indeed, fays, that 4 perfons very 4 much emaciated with the flux or confump- 4 tion are feldom or never feized with the 4 fcurvy *.' I fuppofe fo careful an obferver would ulc terms accurately, and more con- fidence may, perhaps, be placed in his ex- perience in the fcurvy, than in that of ail • F. 508. S 2 other 132 OBSERVATIONS other writers put together. But in Mr. Ives's Journal it is faid, that 4 five or fix fcor- 4 butic men, who had eoughs, are now in 4 deep consumptions*.' Again he fays, 4 ulcerated lungs is a common confequence 4 of the fcurvy+.' Dyfpncea, tightnefs and pain of the breaft with coughing, are among the ordinary fymptoms of the fcurvy; nor will this appear extraordinary to a perfon who confiders that neither the lungs, nor the left auricle and ventricle of the heart, perform their functions properly. It is therefore very poffible to confound the pulmonic fymptoms of phthifis with thofe of fcurvy, though they feem perfectly diftinguifhable, by the abfence of hectic fe- ver in the latter cafe, and by their yield- ing to vegetables. I have already endea- voured to fhew, that very frequently the im- mediate caufe of death in the fcurvy is the difeaied ftate of the contents of the tho- rax ; and if all circumftances be imparti- ally coufidered, we fhall conclude that Mr. * p. 92. -J- p. 107. Mny there not be fcorbutic ulcers of the lungs ? Ives's ON CONSUMPTION. 133 Ives's account is not explicit enough to fa- tisfy us, what effect phthifis produces upon the fcurvy; whether the two diforders g& on together, and whether the ulcerations of the lungs are fuch as take place in phthifis, accompanied with tubercles, &c It would be curious to know how the flow and feeble pulfe, natural to fcurvy*, is mo- dified by thofe caufes which in phthifis render the pulfe fo frequent and fo hard. Lind relates, from his own experience, that in the Saliflbury man of war,in May 1747, *_ when there prevailed feveral inflammatory 4 diforders, particularly peripneumonic fe- 4 vers, or inflammations of the lungs, all who 4 were recovering from them became highly 4 fcorbutic -f-.' This obfervation is fo far from forming a difficulty in the way of any part of the preceding theory, that it re- markably confirms v. hat has been faid of fcurvy. Thofe who die of pneumonia die, I believe, of fuffocation; the counte- nance appears bloated, difcoloured, and li- * Lind, p. 108. t P- 74- vid : 134- OBSERVATIONS vid : even when the expectoration, upon which fo much depends, goes on favourably, we may reafonably fuppofe that lefs oxy- gene will be received through the lungs than in perfect, health during that debility of the thoracic organs which fucceeds the ftate of inflammation. Hence the fcurvy will eafily come on, when its exciting caufes are at hand. I do not know whether the emaciation preceding and accompanying phthifis will be allowed to afford me any additional prefumption. Consumptions have been faid to originate from the abufe of vinegar and' four fruits; but here I believe there is an • inaccuracy in terms. In fome inftances of the diforder arifing from this caufe, I have obferved it to affect the abdomen, and not the thorax. The ftomach and bowels are probably burned by the long continued ap- plication of even weak acids; and hence atrophy cnfues, as the chylopoietic vifcera become unfit for the office of nutrition. The ON CONSUMPTION. 13,- The beneficial effect of the mineral acids in allaying the hectic fymptoms for a fhort time would be a contrary probability, if acids have not fome immediate action, independent of their cempofition. The ufe of nitre in incipient phthifis, if nitre, which I doubt, be really beneficial, Would alfo form another objection.—It would therefore be rafli to place much confidence on fo incom- plete a theory, however ftrongly it may feem to be favoured by fome of the princi- pal phenomena. If I might even take it for granted that excefs of oxgene is a well- afcertained circumftance in phthifis, it would ftill remain to be determined, before the in- veftigation could lead to any thing ufeful, what rank it holds among the other devia- tions from a ftate of health obfervable in this difeafe. Here two fuppofitions occur: 1. The phthifical inflammation may fo alter the flrueture of the lungs, as to caufe them to tranimit a more than ordinary portion of oxygene to the blood; or, 2. Some un- known 136 OBSERVATIONS known caufe having enabled them to tranf- nak, or the blood itfelf to attract, more oxy- gene, an inflammation of the lungs might enfue *. The following obfervations of Mr. La- voifier may perhaps affift the reader's re- flections, as well as illuftrate feveral points of the preceding difquifition. That great philofopher had confined a Guinea pig for an hour and quarter in 248 cubic inches of * During fthenic inflammation, does not a too rapid combination of oxygene take place, of a kind fimilar to the fecondary combination defcribed above, in confe- qaence of which blood changes from fi©rid to black ? May not the heat attending inflammation depend upon this fecondary combination 2 Does not the livid colour fuccceding violent inflammations countenance this fup- pofition ? or is that colour foJely owing to ftagnant ex- travafated blood, in which the oxygene undergoes this fecondary combination ? We muft feek the explana- tion of the mechftnifin of fuch changes in the prin- ciples of chemiftry; and the knowledge of this me- chanifm will not fail to be ufeful. If, for inftance, the above hypothefis were true, it would not be difficult to draw from it fome prafHcal inferences refpecllng the prevention of gangrene. I oxygene ONCONSUMPTION. 137 oxygene air. 4 Towards the clofe of the 4 experiment,' fays he, 4 the animal ap- 4 peared to fuffer Confiderably. Neverthe- 4 lefs, only a very fmall portion of the air 4 was vitiated, i. e. converted into fixed air ; 4 there remained, after the animal was re- 4 moved, much more vital air than is ne- 4 ceffary to conftitute a falubrious atmo- 4 fphere ; this circumftance,' viz. the diftrefs and death of animals confined in oxygene air, long before it had become unfit for re- fpiration, 4 had been noticed by Dr. 4 Prieftley. Having occafion to repeat fome 4 of his experiments, I chofe Guinea pigs 4 for the purpofe: the air in which they 4 were confined, was nearly pure ; it did not 4 contain above five or fix parts in an hun- 4 dred of azotic air. Although the animals 4 lived much longer in this than they would 4 have done in an equal volume of atmof- 4 pherical air, they neverthelefs all died 4 long before it was completely vitiated; 4 and other animals introduced into the air ' in which they had died did not appear to 4 fuffer, at leaf! for fome time. It is not t 4 therefore 138 OBSERVATIONS 4 therefore for want of air fit for refpira- * tion that animals die in vital air, but from 4 fome noxious effect of that air. 4 Dr. Bucquet aflifted at fome of my ex- 4 periments ; and we opened the animals 4 that had died in vital air. In every in- 4 fiance death feemed to have been occa- 4 fioned by an ardent fever, and an inflam- 4 matory difeafe. The flefh was of a very 4 red colour ; the heart livid, and turgid with 4 blood, efpecially the right auricle and ven- ' triele; the lungs were very flaccid, but 4 very red, even externally ; they were alfo 4 turgid with blood.' [Mem, de la Societe R. de Medicine, t. V. p. 5-5—576*) The unufual animal heat, which muft have been generated in thefe experiments, the ftimulant power, which, independently of the heat, oxygene confers upon the blood, that irritability which it communicates to the folids; all thefe caufes might eafily produce the inflammation obferved by Mr. Lavoifier. Now may not the flower and differentlv ON CONSUMPTION. 139 differently modified inflammation of the lungs, in phthifis, originate from a fmaller excefs of oxygene thrown into the fyftem in a more gradual manner ? According to the former of the two fup- pofitions ftated above, we might hope fome- times to fucceed in curing the difeafe by withholding oxygene, and giving the pul- monary ulcers an opportunity to heal; ac- cording to the fecond, the difeafe would be ftill more in our power; by removing the caufe that produces and continues it, we might, with greater certainty, expect the inflammation to fubfide. Of thefe hypothefes, I think it fome re- commendation that they lead to a project totally different from the nugatory modes of practice heretofore employed. The treatment they fuggeft is fo obvious, that it is fcarce neceffary to add a fyllable on the fubject. Fruits, herbs, milk, &c. with all their cooling and all their occult qua- lities befides, have never, I fuppofe, effected a cure of phthifis; nor am I acquainted T 2 with i4o OBSERVATIONS with any reafon capable of fatisfy ing a per- fon at all folicitous in forming his opinions to difcrirninate truth from falfehood, that they have ever contributed towards a cure. While the difeafe is forming, indeed, at which time the diforder feems to be highly inflammatory, an oppofite diet may accele- rate its progrefs. But there will, probably, be little difficulty in prevailing upon men of reflection to avoid both a vegetable and a fli- mulating diet; and to put their phthifical patients upon fuch a diet as, according to the idea of that difeafe already fo frequently re- peated, fhall tend to produce the fcurvy. Not only falted meat, but an oily diet, may be tried. It will not however, I imagine, avail us much folely to cut off the fupply of oxygene by the ftomach. The lungs themfelves being difeafed, and alfo being the moft copious fource of oxygene, it would be moft advantageous to fupply them with an air fuited to our purpofe; fuch an air fhould be mixed either with an addi- tional quantity of azotic or with hydro- gene air, which feems to have no irritating quality, and has been found to have the power O N CON SUMPTION. i+l power of darkening the colour of the blood. We cannot expect benefit from the air of a crowded room, fince its temperature may counteract the effect of its diminifhed pro- portion of oxygene. It is poffible, but by no means certain, that the fleams abounding in fuch a room, which have been compli- mented with the title of putrid, may be injurious to confumptive perfons. Till fome means of lowering the ftandard of at- mofpheric air, without adding to it any thing hurtful, fhall be contrived, we may remove phthifical patients out of thofe airy fpacious apartments which of late have been thought falutary in all difeafes indifcrimi- nately. They may at leaft fleep in confined rooms; and the more confined the better, provided a cool temperature be main- tained. Here it may be afked, with reference to this practice, whether confumptions deftroy a larger proportion of the inhabitants of the town or the country. I fhall have oc- cafion to fay a few words on this fubject below. Hi OBSERVATIONS below. In the mean time, we can fcarce expect any effect from the ftate of the at- mofphere, fince it appears to contain an equal quantity of oxygene air in the moft populous city and the clofeft weather *. It has fometimes been fuppofed that hce* moptoe and phthifis have been produced by quickfilver -f; and this fluid metal has been * According to the experiments of Mr. Scheele and Cavendifh. ■{• In the fcurvy, preparations of quickfilver in ex- treme fmall quantity produce a copious and dangerous falivation, almoft always attended with bloody ftools. (Lind, p. in.) A tendency to falivation is frequently obferved in fcorbutic perfons, independent of quick- filver. The chemical condition of the fyftem, I fup- pofe, is the caufe of the firft mentioned appearance. But in what this corafifts, I cannot form any fatis- fa&ory conjecture at prefent. I think it alfo not pre- fumptuous to expect from chemiftry the explanation of the peculiarity, which appears in fome perfons, whofe fkin is no fooner touched with quickfilver ointment than it is felt in the falivary glands. Moft idiofyn- crafies depend probably upon fomething peculiar in the chemical composition of the fyftem. Of fuch effects there muft be determinate caufes; and I fee none fo ON CONSUMPTION i43 been imagined to increafe the momentum of the blood fo much as to break through the loofe and tender veffels of the lungs. This is a very clumfy account of the be- ginning of phthifis, and fuch grofs mecha- nical ideas are doubtlefs inapplicable to the motions of the living fyftem. Quickfilver is taken in oxygenated, and thrown out re- duced ; and the properties of oxygene, and its afcertained connection with the functions of animals, feem to afford a far more appro- priate explanation of the phenomenon. The fact, if it might be explained in this way, would corroborate a fuppofition which is fuggefted by a common appearance ; the fuppofition is, that the hyper-oxygenated ftate of the fyftem precedes thofe fymptoms which characterize phthifis. I am inclined to believe that the fatal and peculiar inflam- mation of the lungs, whether indicated by acute pains in the cheft, fpitting of pus, &c. likely as this: I do not, therefore, wonder that thefe phsenomena have hitherto appeared fo unaccountable; for we have totally wanted data to explain them. is r44 OBSERVATIONS. is pofterior to the accumulation of oxygene. In perfons only threatened with confumption, and before any formidable figns of difeafe in the thorax occur, we often obferve hae- morrhages from the nofe (in which I have thought the blood preternaturally florid) as well as a remarkable brightnefs of the com- plexion. Thus Mr. Portal, the celebrated anatomift, and one of the lateft obfervers, fpeaking of perfons, menaces de lomber dans la phtkifie, mentions the rongeur fouvcnt habituelle de leur vifage*: this indeed is a very common place obfervation. I add a general confideration, which may poflibly induce the phyfiologift to weigh the pretenfions of the foregoing hypothefis with deliberation. The functions of the lungs feem to have been determined by mo- dern experiments with great precifion; they are deftined to tranfmit oxygene to the blood, while at the fame time a quan- tity of carbone and hydrogene paffes off in a contrary direction, and uniting with the oxy- % Efprit des Journeaux, Mars, 1702, p. 362—2. 4 gene ON CONSUMPTION. I4$ gene of the atmofphere, forms carbonic acid and water. Hence one might conjecture that the lungs will be apt to deviate from an healthy ftate in two oppofite ways; in one of their morbid conditions, the combi- nations that take place within the thorax will be impeded; in another, they may be carried on to too great an extent j and then, the lungs being the principal focus of animal heat, they might be injured by be- ing conftantly expofed to too high a tem- perature, or by having too much oxygene offered to the attractive power of their own fubftance, Here I forefee, without dreading, a fpe- cious objection. 4 Since the lungs aredimi- 4 nilhed during the progrefs of phthifis, is it 4 likely that they fhould, with a narrower 4 area, carry on, to too great an extent, the 4 combinations to which they are deftined ? 4 Is it not alfo to be expected that the inflam- 4 mation fhould render them lefs permeable ?' It might be replied, that the great mifchief feems to be done before they are either u much- ?4cT OBSERVATIONS much thickened by inflammation, or wafted by abforption. Befides, it is common enough for oppofite conditions to exift ei- ther throughout the whole fyftem, or in a particular organ, at different periods of a difeafe, as excefs of action is followed by debility. I however think it probable that inftances have occurred, where the lofs of a confiderable part of the fubftance of the lungs has checked the progrefs of the difeafe. I knew a perfon who died, after a tedi- ous ftruggle, of phthifis. The ribs on one fide were preffed quite inwards, in con- fequence, I fuppofe, of the deflruction of the correfponding lobe of the lungs. From this time, the difeafe, which had at firft proceeded at its ordinary rate, went on wonderfully flow ; and it was not till feveral years after the depreffion of the ribs that the patient died, without ever having had a dif- tinct and long continued intermiffion. How- ever this may be, in the generality of cafes actual obfervation fhews the objection to be groundlefs. In the various fhades of livid colour, which are produced by a total or ONCONSUMPTION. i47 sr partial exclufion of that portion of oxy- gene, which enters the blood by way of the lungs, we have nearly as good a criterion of, any confiderable deficiency of this principle as we can defire. Now I believe it feldom or never happens that a livid fuffufion over- fpreads the countenance of a phthifical pa- tient: les rongeurs, fays Mr. Fortal, aug- mententprefquejufqu au dernier moment; and in proportion as the dark-red afthmatic flufh is a ftranger to this difeafe, we may infer that even the phthifical dyfpncea does not prevent a full fupply of oxygene. The more you reflect, the more you will be convinced that nothing would fo much contribute to refcue the art of medicine from its prefent helplefs condition, as the difcovery of the means of regulating the conftitution of the atmofphere. It would be no lefs definable to have a conve- nient method of reducing the oxygene to 18 or 20 in 100, than of increafing it in any proportion. The influence of the air we breathe is as wide as the diffufion of the u 2 blood. r4S OBSERVATIONS blood. The minuteft portions of the or- gans of motion, fenfe, and thought muft be affected by any confiderable change in this fluid. Whether it be that the brain muft be wafhed by ftreams of arterial blood, or that the action of every organ is a ffimulus to the fyftem in general, and confequently to every other organ in particular, it is certain* that when the accefs of oxygene is cut off from the lungs, the functions of the brain ceafe: perhaps there may be a mixture of azotic and oxygene airs more favourable to the intellectual faculties that that which is found in the atmofphere ; and hence che- miftry be enabled to exalt the powers of future poets and philofophers. That dif- eafes of excitement on the one hand, and debility on the other might be cured almoft folely by a proper air one can hardly doubt, as well as feveral diforders at prefent highly dangerous or defperate, which one cannot, upon the faith of any obvious phsenomena, re- fer to either head. The materia medica might, therefore, undergo a ftill greater reduction, ■*han it has lately undergone in confequence of O N C A T A R R H. 149 of the purification of medicine from its groffer abfurdities ; and hence the treatment -of difeafes be at once rendered infinitely more pleafant and more efficacious. The extreme frequency of consumptions in Great Britain feems to have been juftlv afcribed to the variablenefs of the climate. A few reflections will, perhaps, render it probable that the caufe is adequate to the effect, at leaft that it is peculiarly calcu- lated to excite pulmonary inflammations, with the concurrence of other circumftances. Climates of equable warmth appear to be moft favourable to health, and much the moft congenial to the human race. Next to thefe may be placed thofe climates which have fixed feafons; the moft deftructive are the variable. In England we feldom en- joy any continuance of fettled fine weather, except towards the clofe of fummer and the beginning of autumn, and even then we are frequently baulked in our expectations of fine weather. The fudden changes that take place during three fourths of our year 1113V t$o OBSERVATIONS may be regarded as no lefs prejudicial to the health, than difagreeable to the feelings; and our terrors of catching cold, which have frequently appeared ridiculous to foreigners, are really better founded than we ourfelves are apt, moft of us, to apprehend ; colds, in their confequences, proving fatal every year to multitudes both of the young and the old; to the former principally by giving rife to eonfurnptions, to the latter by pro- ducing pulmonary difeafes of a different character. We cannot hope entirely to efcape the unpleafant fenfations, or to ward off the fa- tal effects, occafioned by this caprice of our climate. But by underftanding how colds are caught, we may be induced to take certain fimple, but ufeful precautions. One may with the greater propriety embrace an opportuniting of diffeminating this fort of in- formation, as the manner in which colds or inflammatory cattarrhs is taken, though now in my opinion perfectly afcertained, is far from being generally underftood by the members O N C A T A R R H. 151 members of the medical profeflion; and if any perfon, not belonging to that profef- fion, fhould fufpect this to be a wanton pa- radoxical affertion, he may find in the cafe of opium, and of the cool treatment of fmall pox, &c. inftances equally ftriking, where one generation of pathologifts palled away after another, without being able, in the cafe of opium*, to perceive the plaineft ap- pearances, or, in that of fmall-pox, to draw the fimpleft conclufion. So fervilely imi- tative an animal is man ! fo loath to employ his own powers of perception and thought! * It is curious to fee what pains medical writers have taken to imagine hypothefes, either out of mere com- plaifance to the term, narcotic, or becaufe opium is a drug in Chriftendom, and wme an article of diet, rather than fiiifer themfelves to fee that opium makes a man merry or drunk, then lays him afleep, and afterwards caufes him to awake with an head-ache, in the fame manner as wine. One cannot compare Haller*s clear and fatisfactory parallel of wine and opium, pub- lifhed in 1769 (Et. Phyfiolog. t. V. p. <5io—n) with Cullen's perplexed and hypothetical doctrine of opium, and his whole article fedanha, publifhed in 1789, (Mat. Medica, t. II 217, & feq.) without a fenfe of humi- liation. When i$2 O BSE R VAT TONS When any part of the body has been expofed to cold, it is liable to be much more affected by heat and other ftimuli than before the expofure. Of this the method of treating frozen limbs in cold countries aflbrds a beautiful and decifive proof. Were a frozen limb to be brought before a fire, or immerfed in warm water, a violent inflammation would come on, and fpeedily terminate in mortification. They therefore take fnow to rub the parts be- numbed with cold, and very gradually ex- pofe them to a warm temperature. The glow, after coming out of the warm bath, is entirely owing to the lower temperature to which the body has immediately before been expofed, or, what amounts to the fame thing, the power of water to con- duct heat away from the body fafter than air. The pungent pain felt upon hold- ing an hand much chilled to the fire is ano- ther exemplification of the fame principle, which feems to be one of the moft gene- ral laws of animal nature. In like manner the ceffation of action and thought during 3 fleers ON C A T A R R H. 15 j fleep accumulates a power of thinking and acting with more energy than before we fell afleep. Even Dr. Cullen, whom the pre- judices of old age and the pride of celebrity confpired to hinder from receiving this doc- trine in its full extent, in his laft work ex- preffes himfelf upon the article of fleep with a precifion that is not always found in the theoretical part of his writings; 4 a ftate of 4 fleep,' fays he, 4 fubfilling for fome time, 4 induces a ftate of the fyftem more ready 4 to be affected by ftimuli of all kinds *.' The latter part of the fentence is a very accu- rate and luminous interpretation of the common expreflion, that we are refrefhed by fieep. * Materia Medica, II. 228. In his little book on phyfiology fome ingenious hints towards this doctrine will be found : Brown doubtlefs profited by thefe hints, and, I fear, without due acknowledgment; the old Profeffor, on the contrary, who had gone into other theo- ries, which he outlived, could not bear to think that 3. man, who had been almoft his fervant, fhould have ma- tured his ideas into a fyftem highly ingenious and partly juft. Nov/ 154 OBSERVATIONS Now after the application of cold, which, according to circumftances, produces a greater or fmaller diminution of the actions of the living fyftem, and at length fleep itfelf, there may be an infinite number of grada- tions between a fatal inflammation and a tranfitory glow, and this according as the previous cold and the fubfequent heat have varied in intenfity; but whatever be the degree, the effect depends on the fame principle. By refpiring a cold at- mofphere the fame thing happens to the noflrils, fauces, lungs, as to the external furface of the body upon going into a cold bath ; and if we pafs fuddenly from fuch an atmofphere into a warm room, what happens to the fkin will in fome degree happen to the membrane lining thefe ca- vities j a glow or inflammation will enfue, according to the difference between the two temperatures and the length of time paffed in the cold. When the application of cold or moifture to a fuperficial part only is fucceeded by an inflammation of the re- fpiratory cavities, the confent of the. whole fyftem ON CATARRH. 1-55 fyftem eafily explains this remote local af- fection. The caufe of difeafe pervades at once and feels as it were, or fearches the whole body, but affects only in a degree to draw our notice to the organ which from habit or flructure is moft tender. Should any other part, from previous circumftances, have been 1 rendered more fenfible to its influence, we fhall in confequence have a fore throat, a diarrhoea, or the rheumatifm, in place of a catarrh. Children are fo fufceptible of in- flammations that a great part of the mor- tality among them is, as far as I have ob- ferved and can judge, to be afcribed to the ignorance of mothers and nurfes of the power which even a moderate change of temperature, if fuddenly made, has to af- fect their tender and irritable frame. When- ever accurate regifters of the mortality of the human fpecies, in climates equably warm, fhall be kept, I expect that not half fo many infants will be found to die as in Britain. Hence, in part, the populoufnefs of fuch countries: thofe gardens of the x 2 earth J5-6 OBSERVATIONS earth being equally calculated to rear and fupport inhabitants. . In catarrh therefore, whatever be the de- gree of inflammation, from the flighteft af- fection of the noftrils or cheft to the moft acute pleurify, it never takes place, unlefs we pafs too fuddenly into a comparatively warm atmofphere, or apply a ftimulus equi- valent to heat. The feverifhnefs, the inter- nal glow, the drynefs of the noftrils, the hufizinefs of the bronchia?, are never felt while we remain in the cold; they fpeedily come on after entering a wrarm room. Per- fons who can recollect their paft, or will at- tend to their future fenfations, will eafily be convinced of the truth of this fimple and falutary theory. Formerly, when I firft heard it, I muft own that I durft not be- lieve it on account of its fimpllcity*. It was # As far as I can judge from recollection, the follow- ing latent hypothefis was a great caufe of doubt. Ana- tomy feemed to demonftrate a wonderfully complicated ^ructure in the human body. It was obvious to ima- ges ON CATARRH. r57 was not till having been made more atten- tive to facts by a defire to determine the merits of the different theories of catarrh, that I was irrififtibly convinced by my own per- fonal experience of the juftnefs of that fhortly ftated above, and which indeed requires but very few words for its expofition. Fre- quently after riding for hours in the rain, efpecially during fummer, I have felt a glow infinitely more vivid than in coming out of the cold bath. This glow was owing partly to the temperature of the atmofphere, and partly to the flight exercife of changing cloaths. I have fometimes made other per- fons attentive to the progrefs of the phseno- mena, and nothing has appeared more evident than that during expofure to wet or gine that the functions or ufe of this complicated ftructure muft be complicated in proportion. This is a falfe con- ception : the living body is in reality infinitely more fimple than it appears at firft view, at leaft as to the actions and difeafes of its parts; and the ftructure is but a conftant repetition of nerves, blood-ve/fels, cel- lular fubftances, fibres, and fat. The anatomical know- ledge of a furgeon, indeed, muft be minute, but it is not abftrufe; not much more lb than th.it of geography. It js perfectly analogous to fubterraneous geography. Cold, i5S OBSERVATION S cold, no tendency to inflammation is per- ceptible, but that fubfequent heat, exer- cife in the dry, and ftimulants, produce the glow or inflammation. By keeping quiet and cool for fome time after being wet in fummer, and by avoiding a fudden tranfi- tion into a warm temperature in cold wea- ther, and by temperance in both cafes, thofe inflammatory difeafes, for which cold only prepares the fyftem, may be eafily avoided ; and any perfon, by acting upon thefe principles, may have at pleafure a flight or a violent catarrh, or no catarrh at all. The popular treatment, therefore, of colds during their early ftage is juft as prejudicial, as the ancient hot regimen during the fmall- pox. Warm or fpirituous liquors, warm clofe rooms, and a weight of bed-clothes cannot but aggravate the fymptoms. The fame may be faid of Mudge's inhaler, which though certainly ferviceable in the afthenic catarrh, or catarrh us fenilis, I have oftener than once obferved fenfibly to heighten ON CATARRH. 159 heighten the inflammation at the com- mencement of a common cold *. It * Catarrhum igitur e frigore efj'e, calore folvcndum, graviffunus error efi. Contra, frigus nunquam nocet, nifi ubi ejus actionem calor excipit.-----Catarrhus aflate toties incidens, ubi fexcenties caufa ejus a frigore fupra re- peti nequit, a calore pot efi ,• contagiofus nunquam, commu- nis fape; frigoris egens; non omnino frigori, calori pro- titius fuccedens ;-----obfervationem condemfirmant. Such is the doctrine of Brown, (Elem. Medicin. II. 42, 43) a noted author and teacher, as he is ftiled by Cullen, (Mat. M. II. 235.) who wras very defirous to perfuade himfelf that the adverfary whom he notes, and againft whom he protefts, was contemptible. For my part, I confider his doctrine of the effect of fti- mulating powers applied to accumulated excitability as the only fpecimen of extenfive reafoning in patho- logy, calculated to afford any fitisfaction to a juft thinker. He avoids thofe unmeaning or vague terms, that had been before fo much employed to flielter igno- rance from their employers and from others ; he appeals to phsenomena of the living fyftem obvious to the fenfes ; and adopts fuch principles of reafoning that, if he has not always difcovered the truth, he is feldom forfaken by the ipirit of a philofopher. I be. It is in this equi- librium 174 GIRTANNER ON THE librium between the acting ftimuli and the irritability furnifhed by the lungs and the circulation, that the health or the tone of the fibre confifts. When the fum of the fti- muli acting upon the fibre is not great enough to carry off all its excefs of irrita- bility, the irritable principle accumulates in the fibre, and then it is found in that ftate which I call the ftate of accumulation ; the irritable principle accumulates in the fibre, its irritability is augmented, and the Ilimuli produce much ftronger contractions than when the fibre only retains its tone. Hence.it is that in oppofing an obftacle to the movements of the hedyfarum girans for any length of time, the movement becomes confiderably ftronger after the obftacle is removed. When the fum of the ftimuli acting upon the fibre is too great, the fibre is deprived not only of the excefs of its irritability but alfo of fome portion of the irritable princi- ple neceffary for the tone of the fibre, or, more properly fpeaking, the fibre lofes more irritability LAWS OF IRRITABILITY. 175 irritability than it receives, and of courfe in a fhort time finds itfelf in a ftate of ex- hauftion, and this exhauftion will be either temporary or irreparable. In the ftate of temporary exhauftion the fibre lofes its tone, and fails for want of ir- ritability. The application ofx a ftimulus, while it is in this ftate, will not make it contract. Provided the ftimulus be not very ftrong, it will produce no effect at all, but in a fhort time the irritable principle will ac- cumulate afrefh in the fibre, and then it will again contract. It is only by little and little that the fibre recovers its irritability. This truth, I dare venture to fay, is as new as it is ftriking. It unfolds a vaft number of phsenomena hitherto inexplicable. Let us obferve, for example, the motion of the heart; the heart contracts from the fti- mulus of the blood, and impels the blood through the arteries; it then again dilates, and the blood enters. But the heart does not contract itfelf immediately upon the firft impreflion of the blood. Its irritabi- 176 GIRTANNER ON THE lity having been leffened by the preceding contraction, it requires half or three quar- ters of a fecond before the irritability of the heart fhall have accumulated to fuch a degree that the new ftimulus can act upon it. It is impoffible to explain the motion of the heart upon any other principle. Hal- ler has indeed very well explained the motion, on the principle of the irritability of the heart; but he was never able to an- fwer the famous objection of his opponents, who faid, If the blood acts upon the heart as a ftimulus, and its contraction is the confequence of fuch action, how comes it that the heart does not contract as foon as the blood enters it, but that it flows in fome time before the contraction is renewed ? Why does not the effect immediately fol- low the caufe ? Haller could never anfwer this objection, nor feveral others of the like nature, inafmueh as he was a ftranger to the laws of irritability. The menftrual dif- charge in women is explained on the fame principle. The ftimulus of the ovaries act- ing continually in women after the age of 2 puberty LAWS OF IRRITABILITY. 177 puberty (as I fhall prove elfewfiere) never- thelefs does not produce its effects till the end of eight and twenty days; becaufe this period of time is neceffary for the uterus, in its ftate of health, to accumulate its ir- ritability in fufficient quantity for the fti- mulus to act; the difcharge ceafes after the irritability of this organ has been dimi- nifhed and returns with the returning irri- tability. All the periodical motions in ani- mals and plants, as well as their periodical difeafes, may be explained upon the fame principle; that is to fay, any ftimulus Which is always prefent, and continually acting upon the fibre, produces no fenfible effect, till the exhaufted irritability of the fibre fhall have been accumulated afrefh. The periodical motions in organized bodies depend on th€ alternate exhauftion and ac- cumulation of the irritability of the fibre. A temporary exhauftion of the irritability of the hedyfarum girans is produced by the heat of the fun and by electricity, accord- ing to the obfervations of M. Brouf- fonet. The electrical fluid exhaufts alfo 2 a the 178 GIRTANNER ON THE the irritability of the mimofa pudica for fome time, as the abbe Berthoion has ob- ferved. The total or irreparable exhauftion of the fibre confifts in a total lofs of its irri- tability, as in the cafe of gangrene. The fibre changes its colour, becomes dark or black, and fubject to the laws of inorganized matter, and begins to decompofe and putrefy. A very powerful ftimulus will in a very fhort time reduce the fibre to this ftate. Such, for inftance, is the ftate of the fibre in animals killed by very ftrong poifons, by the bite of a rattlefnake ; in animals deftroyed by a knife dipped in the juice of the aco- nite, or by poifoned arrows. The irritabi- lity of many infects, and of tfye gr§tfteft part of plants, is irreparably exhaufted by the fti- mulus of the propagation of the fpecies, fo that they die the moment the work of ge- neration is completed. Dr. Prieftley has obferved, that in expofing plants to the ftimulus of air in which animal fubftances have LAWS OF IRRITABILITY. 179 have putrefied, it always happened that, ei- ther the plants being vigorous enough to bear the action of the ftimulus, their growth was very rapid, or the ftimulus proved too pow- erful, and the plants died; their irritability was exhaufted in an inftant, and their leaves became black and gangrenous. The irritable fibre, from the firft moment of its exiftence to that of its diffolution, being conftantly furrounded by the body which acts upon it, and ftimulates it, and upon which it re-acts by its contraction, it follows, that during the period of its exift- ence the irritable fibre is in continual ac- tion ; and its exiftence confifts in action -s and that it is not a paffive ftate, as fome au- thors have afferted. Hence, external ob- jects having no immediate action upon the nerves, and only acting upon them, and producing their different fenfations, through the medium of the irritable fibre, it is plain that the ideas we have of external objects are not conformable to thofe ob- jects, but that they are varied and modified 2 A 2 by s'6f GIRTANNER ON THE by the irritable fibre through which they are tranfmitted to us. Objects, therefore, appear different according to the different ftates of the fibre. The irritable fibres, which are combined together in every i»r dividual, whether animal or vegetable, form a fyftem of fibres, in which the integral parts act continually upon the whole, while the whole re-acts, upon the parts, fo that every ftimulus which acts upon any fibre in the fyftem will deprive that part of its irritability; but this lofs will foon be repaired by the fyftem, and every fibre will furnifh, in proportion, fome fhare of its own irrita- bility to fupply the lofs in any one fibre. Thus it is that a very weak ftimulus, but one that is conftantly acting upon one part of the fyftem, fuch as flow poifops, the abufe of fpirituous liquors, &c. exhaufts in the end the whole fyftem, and produces death. For the fame reafon, a very powr erful ftimulus applied to one part of tjie fyftem, fuch as laurel water, opium, the poifon of the rattlefnake, will in an inftant exhauft all the irritability of the fyftem, deftroy LAWS OF IRRITABILITY. ifgi deftroy the apimal, and leave the fibre* without any irritability. I am convinced, from repeated experiments, that opium, al^ cohol, ammoniac, a folution of fngar of lead, fulphuric aether, deftrpy animajs by exhaufting the irritability of the whole fy£- tern, and that the mufcles of the animate deftroyed have, by the application of thefe ftj- muli, been wholly deprived of their irritabi- lity. The effect was the fame when theft ftimuli were applied to the muftles and ftp- mach, and when injected into the veins of animals. I have alfo made very curious experiments with the fame fubftances uppn vegetables. The irritable fibres in the fame fyflem have not all the fame degree of irritability. They have different degrees of capacity for $ie irritable principle. The capacity of the fibres is in the ratio of their diftance from the heart. Thofe equally diftant have the fame capacity. Every ftimulus which affefts one of the fibres affects the others at the fame time and in like ma mer. Hence the 182 GIRTANNER ON THE the- fympathy of different and feparate parts and thofe furprifing phenomena which hi- therto have been explained by the harmony of the nerves, although we fee the fame phsenomena in the vegetable kingdom, "which is deprived of nerves. Thefe fym- pathetic phsenomena are obfervable through- out organized nature. Whatever part of the polypus be touched, the whole will contract, and its arms will contract them- felves by fympathy. If a worm be touched with the point of a pin, without wounding it, the whole worm will be feen to contract itfelf; which is a certain proof that the different parts are affected by fympathy. If the flighteft impreffion be made upon one of the leaves of the averrhoa carambola, not only that leaf but all the neighbouring ones, and frequently fome of the diftant ones, will contract themfelves by fympathy. When the irritable fibre has loft its tone, and fails, either from an excefs of the irri- table principle, or from a deficiency of this principle, it is difeafed, and the fyftem of LAWS OF IRRITABILITY. 183 of which it forms a part fuffers and be- comes difeafed through fympathy. All the difeafes of animals and vegetables may be \ ranged under two heads; to wit: Firft, the difeafes of accumulation caufed by the accu- mulation of the irritable principle, and by the diminifhed action of the habitual ftimuli. Secondly, the difeafes of exhauftion, caufedby a defect of the irritable principle proceeding from the encreafed action of the habitual ftimuli, or from the addition of new ftimuli. Under thefe two claffes may be ranged all difeafes whatever. Paradoxical as this pro- pofition muft neceffarily appear to thofe who have not reflected on the fubject, it is neverthelefs true, and I fhall give the moft convincing proofs of it in a work I am about to publifh. Remedies remove the difeafe by their action upon the irritable fibre, and by ex- haufting its irritability, when the difeafe is that of accumulation; or by diminifhing the action of the common ftimuli, and conse- quently by preventing a total exhauftion, where 184 GlRTANNER ON THE where the difeafe is that of exhauftion. The effects of poifons are to be explained in this way. Poifons, remedies, and in general all fur- rtiuriding bodies acting only oft the i fritable fibre, it follows that they- a& upon the fyftem in a fimilar manner, and that every fubftance cap&fete 6f producing the greateft poffible effect upon the fibre, that is to fay* every fubftance capable of exhattfting all the irritability both of the fibre itfelf and of the fyftem in an inftant, as, for inftance, laurel Water, or white arfenic, ia alfo capable of producing all the inferior degrees of ac- tion, either by acting upon a fibre lefe irri* table, or by acting upon the fame fibre, but in a lefs quantity. Laurel Wafer, Opi- um, white arfenic, ammoniac, are of courfe both medicines and poifons capable of healing as well as of producing all maladies Whatfoever without exception. And this is confirmed by a number of experiments which 1 have made upon different animals. This truth feems to me of the utmoft im- 2 portance; LAWS OF IRRITABILITY. 185 portance ; and the abbe Fontana, who made more than fix hundred experiments to prove that ammoniac is no remedy againft the bite of the viper, would have faved himfelf a great deal of time and trouble, had he been acquainted with it. If inftead of applying the venom of the viper to fo many animals, and afterwards applying ammoniac to the wound, he had made a fingle comparative experiment, and had applied ammoniac to a wound made by a lancet that was not poifoned, he would have found that am- moniac itfelf, applied in this manner, would have produced a difeafe exactly analogous to that caufed by the venom of the viper, and, confequently, fo far from removing the malady, muft neceffarily increafe it, by ex- haufting the irritability of the fibre in a much lefs time than the venom of the vi- per by itfelf was capable of doing. Mr. Fontana has made more than fix thoufand experiments upon the poifon of the viper; he employed more than three thoufand vi- pers, and caufed to be bit more than four thoufand animals, and the conclufion he 2 b drew iS6 ©lRTA'NNER ON THE drew after this truly enormous number of obfervations was, that the poifon of the vi- per kills all animals, and produces the dif- eafe by its action on the blood. But why dicUMr. Fontana neglect to make the decifive experiment, the experimentum cruets of Bacon. It is well known that frogs, and many animals with cold blood, live a long time without the heart, and entirely de- prived of blood. If therefore the poifon of the viper kills animals by its action on the blood, it will not deftroy frogs without blood. But experiment contradicts this reafoning. The poifon of the viper will kill frogs without blood in as fhort a time as it kills thofe animals who have not loft v their blood. It is not therefore by its ac- tion upon the blood that the venom of the viper deftroys animals; and thus does it happen that a fingle experiment frequently overturns all that fix thoufand other experi- ments have apparently eftablifhed. Ac- cording t& my experiments, poifons operate upon the blood juft as they do upon the mufcular fibre, by depriving it of its prin- ciple LAWS OF IRRITABILITY. 187 ciple or irritability, or of its oxygene. After having made this obfervation upon the ex- periments of Mr. Fontana, I muft do him the juftice to add, that 1 have found all his experiments very accurate, and that in all thofe which I have repeated, the refult has been exactly conformable to the account given by him; it is in his conclufions only that he appears to be deceived The effect produced upon the irritable fibre by any ftimulus, is in a ratio com- pounded of the degree of irritability of the fibre, and of the force of the ftimulus. The fame ftimulus will produce greater contrac- tions upon a fibre more irritable than upon one lefs irritable; and the irritability of the fibre being the fame, it will contract itfelf more upon the application of a ftronger than of a weaker ftimulus. The effect produced upon an irritable fibre by any ftimulus is in the inverfe ratio of the repetition of its application. Csete- ris paribus, the effect of ;my ftimulus di- 2 B 2 mini it.e> i88 GIRTANNER ON THE minifhes every time its application is re- peated, till at laft the effect is nothing, or = o. This explains the phaenomena of habit, and many other phenomena hitherto inexplicable in the animal and vegetable ceconomy. The mimofa pudica, for exam- ple, expofed to a ftrong wind, contracts it- felf ; but it ceafes to contract itfelf in obe- dience to this ftimulus after it has been ac- cuftomed to it. The effect produced upon the irritable fibre by any ftimulus, is in a ratio com- pounded of the degree of irritability of the fibre and the degree of the force of the fti- mulus directly, and the degree of the ha- bit of the fibre inverfely. Let the force or intenfiry of the ftimulus = a, the de- gree of irritability of the fibre = b, the de- gree of the habit of the fibre = e, then the effect produced upon the fibre or x will =— But all the ftimuli acting in the c fame manner, that which diminifhes the irritability of the fibre for a certain ftimu- lus, LAWS OF IRRITABILITY. 189 his, will in the like manner diminifh it for the ftimulating force in general, wherefore the habit of the fibre is comprehended under its degree of irritability, or c is compre- hended under b. Therefore x will = ab. The effect produced upon the irritable fibre by any ftimulus, or x, being always equal to ab, it follows that the value of a and b being known, the value of x is known. But admitting an unity fixed and conftant, it will be eafy in all cafes to exprefs by num- bers the degree of irritability of the fibre and the degree of the force of the ftimulus, or the value of a and b, confequently it will be eafy to find the value of x. All the art of medicine then confifts in the art of finding the value of x, that is to fay, in finding a ftimulus adequate to reftore the tone of the fibre. Thus, if thefe prin- ciples be true, phyfic, which at prefent is an art of mere conjecture, will be reduced in time to the certainty of calculation, and after tables fhall be formed to exprefs the values of a and b, and the figns by which thcv i9o GIRTANNER ON THE they may be known, this calculation will be fo fimple and eafy, that it will from a part of the education of every individual. But further, the irritable fibre being the fame in all organized nature, difeafes and their remedies will of courfe be the fame for all organized beings : there will then be no diftinction between medicine, farriery, and agriculture, but all thefe fciences will be confounded, and become one, under the ge- neral name of univerfal phyftotogy. The art of pharmacy and the fcience of prefcrip- tion-writing will become ufelefs; a phial of alcohol or laudanum will fupply the place of that enormous quantity of drugs which crowd the fhops of apothecaries. The trade of the druggift—but hold, if I continue this prophetic language, I fhall only expofe myfelf to ridicule; for, as Helvetius obferves, ' every idea very foreign to our habits of fee- * ing and thinking appears ridiculous to us. * We never value any ideas but what are analo- * gous to our own, becaufe we are under the ' neceflity of efteeming ourfelves only in 6 others.' Thofe LAWS OF IRRITABILITY. 191 Thofe ftimuli which I call common and habitual, becaufe they act continually more or lefs upon the irritable fibre, are, heat, light, nourijhment, air, the circulation of the blood, the ftimulus of generation, and the nervous ftimuli. So long as the action of thefe ftimuli is in proportion to the degree of irritability of the fyftem, and the fum of their action is nearly equal to the fum of the irritable principle abforbed by the lungs, and dis- tributed by the circulation, the whole fyf- tem will be in proper order, and the con- ftituting fibres will have their tone. When one or more of thefe ftimuli act more pow- erfully than ordinary, or the fibre becomes more irritable, while the degree of the ac* tion of the ftimuli remains the fame, the exhauftion of the fyftem, and one of the difeafes in its train, will be the confe- quence. The abfence of one or more of thefe fti- muli will produce an accumulation of irri- tability in the fyftem, and give birth to one of the difeafes of this clafs. I fhall fpeak of 192 GIRTANNER ON THE of all thefe ftimuli feparately, in order that I may be better able to explain myfelf. Of heat.—The heat of the atmofphere, and of all furrounding bodies, acts upon the fibre and ftimulates it. I am convinced of the ftimulating action of heat from direct experiments. I have expofed fmall animals, fuch as cats, dogs, rabbits, &c. in covered veffels, to the heat of boiling water, which furrounded the veffel in which the animal was placed, fo that the water could not touch it. Animals deftroyed by heat in thefe experiments, upon diffection have been found to have loft all their irritability. Their heart and mufcles contracted them- felves but feebly, even upon the applica- tion of the ftrongeft ftimuli, fuch as electri- city. It is proved by fome beautiful ex- periments of Mr. Hope, that heat acts as a ftimulus upon plants; and it is obfervable that plants expofed to the fun are larger, and produce more flowers and fruit than thofe which are lefs expofed to heat. Trees in general are more luxuriant which 2 grow LAWS OF IRRITABILITY. 293 grow in the fouth than thofe in the north. This is a proof that heat is a ftimulus to ' the irritable fibre. The difeafes of hot climates are all the difeafes of exhauftion, caufed by the too powerful action of the fti- mulus of heat. Hence the cuftom of tak- ing ice in hot countries to reftore the tone to the fibre, by abforbing the heat and pre- venting its ftimulating action. This irrita- bility of the hedyfarum gyrans is exhaufted by the heat of the noonday fun, according to the obfervations of M. Brouffonnet; and by the experiments of M. Fontana and M. Medicus it is proved that the irritabi- lity of plants is great in the morning, dimi- nifhed during the heat of the day, and lit- tle or none in the evening. Of cold.—Cold being a lefs degree of heat, its effects upon the irritable fibre are In pro- portion to the habit, or the quantity which is neceffary to the fibre to preferve its tone. The animals and plants of hot climates, that require the ftimulus of a great heat to preferve the tone of their lefs irritable fibres, 2 c are i94 GIRTANNER ON THE are affected by the leaft abftraction of this habitual ftimulus j the irritability of their fibres accumulates in confequence of this ab- ftraction, and the return of the heat again exhaufts the fibre. The more intenfe the cold is, the greater is the accumulation of irritability. After the fibre has been ex- pofed for fome time to a great degree of cold, its irritability is increafed to fuch a degree, that the moft trifling degree of heat produces the moft violent effects : hence the glow experienced in coming out of a cold bath; hence the difeafes which are caught in coming out of the cold air into a warm room, and which medical men attri- bute to checked perfpiration, a fuppofition entirely falfe. The leaft movement is attended with fa- tigue upon the fummit of high mountains, as I have frequently experienced, but efpeci- ally in 1785, upon the top of the Buet, and, as M. Sauffure has likewife obferved, upon the fummit of Mount Blanc. The reafon of it is this; the fibre is rendered fo irritable by LAWS OF IRRITABILITY. 195 by the cold of thofe mountains, that the leaft motion of the mufcles, or what is the fame thing, the leaft action of the nervous fti- muli, exhaufts it. It is by the gradual ap- plication only of heat that frozen limbs can be recovered, and it is neceffary always to begin by rubbing them with fnow; with- out this the fibre will be exhaufted, and be- come gangrenous. During the winter, by the abfence of the ftimulus of heat, and in part of light, plants and many animals become torpid, the organs of circulation and of nutrition perform their functions but languidly, and life itfelf appears fuf- pended. In confequence of the diminifhed action of thefe ftimuli, the irritability ac- cumulates, and manifefts itfelf at the return of fpring. The leaft degree of heat then produces the moft violent effects upon the fibres thus delicately irritable. Animals, which had concealed themfelves under ground, venture forth from their fubterra- neous retreats, plants put forth their leaves and flowers, and man himfelf is fenfible of the ftimulus of heat in the gales of fpring, 2 c 2 his :96 GIRTANNER ON THE his fibre being rendered more irritable by the winter's cold. Vegetation is much more vigorous in fpring time than during the reft of the year. It diminifhes during fummer in proportion as the irritability ac- cumulated during winter is diminifhed by the action of heat and light, and, laftly, is exhaufted in the autumn. Dr. Hales ob- ferved, that the rapidity with which the fap circulates in the vine during fpring is five times greater that the rapidity with which the blood flows in the arteries of a horfe. This motion is much flower in fummer, and almoft ceafes in autumn. It is not the effect of the heat alone, for if that were the cafe it would increafe as the heat increafed, and the effect would be proportionate to the caufe ; it is the effect of the irritability ac- cumulated in confequence of the abfence of heat during the winter. The effects of winter are very great in cold climates, be- caufe the accumulation of the irritability is in proportion to the abftraction of the ftimulus of heat. In Lapland corn ripens in fixty days, whereas in France it requires an LAWS OF IRRITABILITY. I97 an hundred and twenty, or an hundred and thirty days. The truth of what is here ad- vanced may be proved by expofing vege- tables alternately to heat and cold: it is furprizing how much their growth and the power of vegetation is increafed. But in thefe experiments care muft be taken to vary the temperature by degrees ; becaufe the ir- ritability accumulating in the fibre by the abftraction of the heat, a very fmall quan- tity of this ftimulus then applied is fuffici- ent to exhauft it entirely, or to deftroy it. Hence it is that the return of cold and froft in the beginning of fpring is fo noxious to vege- tables, and that the year is in general more abundant after a very cold winter. Mr. Fon- tana obferved, that during winter the vipers which he kept for his experiments were in a torpid ftate, though the thermometer was at 590. He endeavoured to render them vigorous by warmth, and expofed them to a heat of 6f only. In two minutes they died, though during fummer they bear a much greater degree of heat; but then they are lefs irritable. Spallanzani obferved that 198 GIRTANNER ON THE that newts bury themfelves in the earth, and become torpid, in the month of October, before the thermometer in the fhade falls to 54^-, and that they re-appear in the month of February, though at that time it freezes every night, and frequently during the day the thermometer is many degrees below 540. What is the reafon, enquires this excellent obferver, that thefe animals revive in fpring, when the cold is more in- tenfe, and fink into torpidity at a much lefs degree of cold in autumn ? I will folve this problem, by obferving that in autumn a verv great ftimulus is required to act upon the fibre of thefe animals, exhaufted as it has been by the heat of the fummer; but in fpring, the leaft ftimulus, the leaft increafe of heat, is fufficient to put the fibre in action, its irritability having accumulated during winter in confequence of the abfence of the common ftimuli. Light is another common ftimulus. To convince myfelf of the ftimulating quality of light upon plants by direct experiments, I enveloped LAWS OF IRRITABILITY. 199 enveloped the leaves of fome plants in an opake body, fo that the air might have free accefs, while the light could not penetrate. I found that thefe leaves became more irrita- ble than the others, the irritability having accumulated. By the abftraction of the ftimulus of light, the irritability of organ- ized bodies accumulates, and a difeafe en- fues, which is called etiolement. Animals deprived of light, and living in dark places, lofe their colour and become white, as is obfervable in arctic animals during the long- nights in the countries near the pole: I have obferved it alfo in the animals that inhabit the Alps, and which conceal them- felves for the greateft part of the year in fub- terraneous dwellings. Blanched plants lofe their green colour, and become whitifh and fickly. Some poifonous plants lofe their noxious qualities, and become agreeable to the tafte, merely by the abftraction of the ftimulus of light. White animals and plants are very irritable; and it is obferved that thefe animals and plants are not capa- ble of fupporting a great quantity of light. The 200 GIRTANNER ON THE The action of the light upon plants has been very well obferved by Dr. Ingen- houfz and Mr. Senebier, and the manner in which colours are produced has been ex- plained by M. de la Metherie. It is well known that animals that have been tamed, and efpecially domeftic animals, change their colour by education ; but an obfervation that has perhaps efcaped naturalifts is, that this change is conftantly from dull colours to thofe that are brighter or lefs dull. I have often obferved, that the change takes place more frequently in dark than in light places. Mice kept in a cage in a dark room have produced white mice. The third common ftimulus is that of nu- triment. It requires a very fmall quantity to fupply the daily loffes; the greateft por- tion is employed in depriving the ftomach, and of courfe the whole fyftem, of its fuper- fluous irritability. This is proved by what is obferved in organized bodies. All ani- mals are more irritable before than after food. Hunger, of which appetite is the 4 leaf! LAWS OF IRRITABILITY. 201 leaft degree, is caufed by the accumulated irritability of the fyftem. The gaftric juice acts upon the fibres of the ftomach now be- come more irritable, and produces the fen- fation of hunger. Spallanzani has obferved that birds of prey do not void indigeflible bodies, fuch as pieces of glafs or metal, which they have taken in with their food, before their ftomach is empty. Thefe in- digeflible bodies cannot be voided while the ftimulus of the nutriment acts upon the ftomach ; but as the abftraction of this fti- mulus gives the irritability of the ftomach an opportunity of accumulating, the indi- geflible bodies very ftrongly flimulate the fibres of the ftomach, make them contract, and by this contraction they are voided. It is poffible to do almoft wholly without nutriment, by applying from time to time fome other ftimulus to the ftomach, fuch as tea, coffee, alcohol, opium, and by ex- haufting by thefe means the accumulated irritability of that organ. By the entire abftraction of the ftimulus of nutriment, 2 D the 26* GIRTANNER ON THE the irritability of the fyftem is prodigioufly increafed. There are many inftances of per- fons who, not having eaten any thing for many days, have been intoxicated, and killed, in confequence of fwallowing, with great greedinefs, two or three cups of broth. Plants fuddenly tranfplanted from a meagre, into a very rich foil, produce no fruits or feeds^ and die in a fhort time of a particu- lar difeafe, caufed by excefs of nutriment. The circulation of the fluids is the moft powerful of the common ftimuli. The blood, which oxygenates itfelf during its paffage through the lungs, parts with its oxygene in the circulation, the oxygene having a ftronger attraction for the irritable fibre than for the carbon which is con- tained in the blood. In this operation the heat combined with the oxygene is fet free. Hence animal and vegetable heat. The blood acts continually upon the irritable fibre, and the fibre re-acts upon the blood, and this action and re-action are ftronger in proportion LAWS OF IRRITABILITY. 2o3 proportion as the circulation is more rapid, and as the air which comes in contact with the blood in the lungs contains more oxy- gene air. When any local ftimulus continues to act upon any part of the fyftem, the cir- culation becomes more rapid, and a fever is the confequence. Is the ftimulus weak, a flow fever enfues, which will by little and little exhauft the irritability of the fyftem, and the patient will die of a confumption. Is the ftimulus ftronger, or the fibre upon which it acts more irritable, we fhall have an ardent fever, which will exhauft the irritability in a lefs time. In fine, is the ftimulus very violent, or the fibre dif- eafed by an excefs of irritability, we fhall have a putrid fever, which will deftroy the patient, whether animal or vegetable, and will exhauft the irritability in a very fhort time. But whatever be the nature of the fever, the fibre irritated by the ftimulus will a& upon the blood more than erdma- 2 d 2 rilv, 204 GIRTANNER ON THE rily, the re-action of the blood will be in- creafed in proportion, the circulation will be more rapid, the blood will abforb more oxygene, and the whole fyftem will be furcharged. By this means the irritability will be increafed, the animal heat aug- mented, and the effect of the action of the ftimulus becoming greater in propor- tion to the accumulation of irritability, a total exhauftion of the irritability, or the death of the patient, will enfue. There are two methods of preventing the fatal effects of a local ftimulus, whofe operation upon one part of the fyftem is conftant. The firft confifts in preventing the furcharge of oxygene in the blood, which is accom- plifhed by diminifhing the proportion of oxy- gene gas in the air breathed by the patient, or by diminifhing the quantity of blood by phlebotomy. The fecond method con- fifts in applying ftimuli capable of exhauft- ing the irritability in proportion as it ac- cumulates ; fuch as wine, opium, bark, heat, &c. Phlebotomy acts by diminifhing the LAWS OF IRRITABILITY. 205 the quantity of blood, and confequently its operation is attended with this effect, viz. of diminifhing the re-action, and reftoring to the fibre its tone. I fhall here obferve by the way that the advice which many phyficians have given, to make the patient breathe oxygene gas, is the moft pernicious they can give ; for the patient always finds himfelf worfe after having breathed this falutary gas, as 1 have frequently had occa- fion to obferve. The nervous ftimulus is the only one which is peculiar to animals. It is this ftimulus which is the caufe of the voluntary motions, of convulfions, and paffion?. The paffions differ from one another only in ftimu- lating the irritable fibre more or lefs. An- ger and joy are very powerful degrees of the nervous ftimulus; content and hope are weak degrees ; fear, forrow, fright, defpair, are not abfolute degrees of this ftimulus, they are only the abftraction of the ftimuli of hope, content, and happinefs. Anger and j°y 206 GIRTANNER ON THE joy act as very powerful ftimuli, and exhauft the irritability of the fibre in the fame man- ner as any other ftimulus whatever. Con- tent and hope are degrees of the nervous ftimulus, neceffary to preferve the tone of the fibre. Sorrow and fright are de- grees too weak. If they continue to act, the irritability of the fibre accumulates. It is well known that fearful and melancholy perfons are oftener affected by the ftimu- lus of contagious difeafes than they who are free from fear, and who take the precaution of applying a greater quantity of ftimulus than ordinary to their fibres, by taking wine, vinegar, opium, and bark. Accord- ing to the obfervations of Mr. Fontana, timid and fearful animals die much fooner of the bite of the viper than courageous or irritated animals. Joy excited by the an- nunciation of good news to a forrowful perfon, and one of courfe very irritable, has often caufed death. The ftory of the Ro- man mother is well known, who was be- wailing the death of her fon, and who dropt LAWS OF IRRITABILITY. 20? dropt down dead for joy the moment fhe faw him enter her room alive. By the abftraction of many of the com- mon ftimuli for any length of time, the ir- ritability of the fibre accumulates fo much, that the moft trifling ftimulus produces the moft violent effects, and frequently even in- ftantaneous death. This difeafe is called the fcurvy, concerning the nature of which me- dical men have formed fo many falfe and ri- diculous theories. It is of the utmoft import- ance to mankind to know the true nature of this difeafe j fince, in confequence of our ig- norance in this particular, we have been un- able to find a fure remedy for it, and fo. many thoufands of lives have fallen a facri- fice to its ravages, in armies, fleets, and be- fieged towns. In the laft war the Englilh fleet fuffered dreadfully from the fcurvy; and laft year a great number of foldiers died of this difeafe in the imperial army in Wala- chia, in confequence of the abftraction of the ftimulus of nutriment (the emperor having 208 GIRTANNER ON THE having ordered that a kind of pafte made of bread and water fhould be given to the foldiers inftead of meat), of the ftimulus of oxygene, in the corrupted atmofphere of the fens of Walachia, and laftly, of the nervous ftimulus, the moft powerful of all; for the greateft part of the army were en- gaged by force, and againft their wills. The abftraction of all thefe ftimuli accu- mulated the irritability of the fibre, and caufed the fcurvy, and that dreadful mor- tality that took place in the army. The fame caufes produce the fame effects upon animals. We fee domeftic animals affected with the fcurvy in confequence of cold and hunger, that is to fay, in confequence of the abftraction of the ftimuli of heat and nutriment. The fheep which captain Cook had on board his fhip, on his voyage round the world in the years 1772, 3, and 4, died of the fcurvy, their teeth fell out, their gums 2 rotted; LAWS OF IRRITABILITY. 209 rotted ; in a word, they had all the fymp- toms of an inveterate fcurvy. The abftrac- tion of the common ftimuli in plants pro- duces fimilar fymptoms and a fimilar dif- eafe. The difeafe of rye called ergot is ex- actly analogous to the fcurvy in animals; the ergot is the fcurvy of plants ; it is the effect of accumulated irritability in the fibres of plants. The caufes which produce the ergot of rye are the fame as thofe which produce the fcurvy in animals. Ac- cording to the obfervations of Saillant and Teffier, thefe caufes are, a wet and bar- ren foil, and a cold fummer; that is to fay, the caufes of the ergot are, the abftraction of the ftimuli of nutriment and heat. I could enlarge upon this interefting fubject, if I were not afraid of making this effay too long. I wifhed to give only the out- lines, or a general view of my theory, with- out entering into the detail. In the fubfe- quent effays I fhall treat of oxygene confi- dered as the principle of irritability, of the compofition and decompofition of water in 2 e animals tio GlRTANNER ON THE &c. animals and plants, of the different kinds of air contained in the interior cavities of or- ganized bodies, and of the circulation of this air, the exiftence of which has not hitherto been even fuppofed, although, as I fhall prove hereafter, the lymphatics in animals, and the fibres in plants, are almoft folely deftined for the circulation of thefe elaftic ^uids. MEMOIR ( *" ) MEMOIR If. Jrl AV1NG given this general fketch* bf a new fyftem of phyfiology, founded upon a number of experiments ihewing that irritability is the principle of life, I proceed to prove that oxygene is the principle of ir- ritability ; that it unites with the blood in the lungs during refpiration; that it is dis- tributed to every part of the fyftem by the circulation, and that it combines with fti- mulating fubftances, with which the diffe- rent parts of the fyftem come in contact. I think that the oxygene is abforbed by the blood, and that the venous blood is oxygenated in the lungs during refpiration. The moft celebrated naturaiiils and chy- mifts are of a different opinion; they think that the oxygene does not combine with the venous blood. According to them ? E 2 this 212 GIRTANNER ON THE this laft lofes carbone and hydrogene, and recovers the bright colour natural to it, without abforbing any thing from the at- mofphere. Here are fome experiments and reafons, upon which their theory of refpiration is founded. i. Arterial blood expofed to the contact of hydrogene air lofes its vermilion co- lour, and affumes the black and deep ap- pearance of venous blood. The hydro- gene air is abforbed in part in this experi- ment. 2. Mr. Hamilton made three ligatures in the jugular vein of a cat. Having expelled the blood from between two of the liga- tures, he then introduced the hydrogene air, and kept it there, clofing the aperture through which he had introduced it. He then loofened the middle ligature, and the blood contained between that and the third ligature came into contact with the hydro- gene PRINCIPLE OF IRRITABILITY. 213 gene air. In about an hour, having taken the blood from the vein, he found it li- quid, and of a colour almoft as black as ink. 3. Venous blood expofed to vital air ac- quires the vermilion colour of arterial blood, and the air is rendered impure. Mr. Lavoifier and Dr. Crawford (Annales de Chimie, torn. V. p. 267) have drawn the following conclufions from thefe expe- riments : 1. That the change of colour which the blood undergoes during circulation proceeds from its combination with hydrogene air. 2. That in pairing through the lungs, the blood parts with a portion of the hy- drogene it contains, and then re-affumes its vermilion colour. Mr. Lavoifier and Dr. Crawford think, that during refpiration the vital air which is 214 GIRTANNER ON THE is received into the lungs combines with the carbone and hydrogene that is dif- engaged from the blood ; that it forms car- bonic air with carbon, and water with hy- drogene ; and that tht blood recovers its vermilion colour after it has loft the car- bon and hydrogene with which it had been charged during the circulation. Without prefuming to contradict philo- fophers of fuch diftinguifhed merit, I can- not help obferving, that it appears to me that thefe conclufions do not neceffarily follow from the experiments, and that they are to be explained in a manner more con- formable to the laws eftablifried by modern chemiftry. I know no experiment which authorizes us to fuppofe that carbone can unite with oxygene in a temperature of 970—990, or that hydrogene and oxygene air combine and form water in fo low a temperature. M. Seguin has attempted to anfwer this objection, by fuppofing that the carbon is in a very attenuated ftate in the blood, and by citing the experiments of M. Ber- PRINCIPLE OF IRRITABILITY. 215 M. Berthollet upon hydrogene air. But this explanation appears to me hypotheti- cal, and no way convincing. After having a long time attended to the phenomena of refpiration, and made many experiments upon this fubject, I think it may be concluded, that during re- fpiration one part of the oxygene of the vital air combines with the venous blood, of which it changes the black colour and makes it vermilion *; the fecond part of the oxygene unites with the carbon con- tained in the carbonic-hydrogene gas, which exhales from the venous blood, and forms carbonic acid air; a third part of the oxy- gene unites with the carbon of the mucus, contained in great quantities in the lungs, and which is continually decompofing ; this part alfo forms carbonic acid air; a fourth part of the oxygene combines with the hydrogene of the blood to form water, which is exhaled during refpiration. The * Dr. Goodwyn had proved this before. Could Dr. Girtanner be unacquainted with his experiments ? heat 2i6 GIRTANNER ON THE heat contained in the vital air being decom- pofed, remains united in part with the oxy- gene and the blood. Hence the quantity of heat peculiar to the arterial blood, which is much greater than that of the venous blood. Another part of the heat enters into combination with the carbonic acid air. Laftly, a third part produces a tempera- ture neceffary for the formation of water, by the combination of the hydrogene and oxygene airs. The effects of refpiration will confe- quently be thefe: i. The venous blood lofes the car- bonic-hydrogene air which it contains, and abforbs the oxygene air, which gives it its vermilion colour, fuch as it gives to metallic oxids, nitrous acids, and many other fubftances with which it enters into combination. 2. The capacity of the blood will be increafed, becaufe oxygene increafes the i capacity PRINCIPLE OF IRRITABILITY. 217 capacity of all fubftances to which it unites. 3. The oxygene air of the atmofphere is partly abforbed by the venous blood, changed in part into carbonic acid air by the carbone of the blood and that of the mucus of the lungs, while the reft forms water with the hydrogene air of the blood, and a quantity of heat is fet free. The products of refpiration will be— 1. Animal oxid, fluid (i. e. arterial blood.) 2. Carbonic acid air. 3. Water. 4. A fmall quantity of liberated heat. Nothing is more eafy than to explain by this theory the experiments above re- lated. 2 F If 2i8 GIRTANNER ON THE If we expofe, under a veffel filled with hydrogene air, arterial blood to the contact of this air, the quantity of air will be di- minifhed* lofe its vermilion colour, and be- come livid. In this experiment exactly the contrary takes place of that which is ob- fervable in refpiration. The hydrogene air unites with the oxygene of the arterial blood to form water, and the arterial blood, being deprived of its oxygene* becomes black, and is changed into venous blood ; the deep colour which it affumes proceeds from the lofs of its oxygene alone. The experiment of Mr. Hamilton proves this. He adds, that he found the blood liquid and very lit- tle coagulable. This is another proof in my favour. I have faid, in my former effay, that the coagulability of fluids obeys the fame laws, and depends upon the fame principle as the irritability of the folids ; confequently, the blood deprived of the irritable principle, or of oxygene, ought to be liquid, that is, to poffefs little or no coagulability, The third experiment is a direct proof that PRINCIPLE OF IRRITABILITY. 219 that the vermilion colour of the blood is owing to the abforption of oxygene. Having (hewn that the arguments upon which the generally received theory of re- fpiration is founded are not conclufive* I proceed to ftate fome direct experiments in favour of the new theory which I wifli to eftablifh. A. Experiments upon venous blood. 1. Six ounces of black venous blood, taken from the jugular vein of a fheep, were introduced into a veffel filled with oxygene air, and in an inftant the blood affumed a vermilion colour) the thermometer within the veffel rofe feveral degrees, but funk again immediately. The mercury in which the veffel was placed rofe from fix to eight lines. When the experiment was finifhed, the blood was increafed a little in weight; but though I am certain of this increafe of weight from repeated experiments I cannot 2 F 2 exactly zza GIRTANNER ON THE exactly afcertain how much it was, becaufe the inftruments I made ufe of for this purpofe were not fufficiently exact for fo delicate an experiment. The oxygene air which the veffel contained was mixed with carbonic acid air, which lime water abforbed. Some drops of water were formed at the bottom of the veffel This experiment proves, that during re- fpiration the blood abforbs the oxygene ; and I make no doubt but it is poffible to deter- mine the weight of the oxygene abforbed, by repeating this experiment with inftru- ments as exact as thofe of M. Lavoifier. This experiment alfo proves, that during refpiration there is formed carbonic acid air and water, that is to fay, that there is an exhalation of the hydrogene air from the blood *. 2. The jugular vein of a fheep was opened, and the blood which flowed from * Rather of the bafe of hydrogene air. it PRINCIPLE OF IRRITABILITY. 221 it was received in a glafs bottle filled with oxygene air. The bottle, when half full, was clofed. The blood which it contained immediately affumed a vermilion colour, became very fluid, and coagulated but flowly into a reddifh and thick mafs, without any feparation of ferum. On the morrow the bottle was opened in order to examine the air which it contained, and the oxygene air was mixed with carbonic acid air. Some drops of water were formed near the mouth of the bottle. This experiment confirms the firft. 3. A confiderable quantity of very pure oxygene air was injected into the jugular vein of a dog. The animal raifed moft ter- rible outcries, breathed very quickly, and with the utmoft difficulty ; by little and lit- tle his limbs became hard and fliff, he fell afleep, and died in lefs than three minutes. Upon opening the thorax and the pericardium, the heart was found more irritable than or- dinary, and its alternate contractions and di- latations 222 GIRTANNER ON THE latations continued upwards o f an hour. The right auricle of the heart was vermilion, and it contained, as well as the right ventri- cle, a great quantity of blood of a bright ver- milion colour, frothy and not coagulated. The blood contained in the left ventricle, in the aorta, and the arteries, was of a rofe colour, and was mixed with bubbles of air. All the mufcles were more irritable than ordinary. After the blood contained in the heart and veins was difcharged, the irrita- bility of the heart and the mufcles fenfibly diminifhed. This experiment appears to me to prove moft decifively, that the vermilion colour which the blood affumes in pafling through the lungs is not owing to the lofs of the carbonic-hydrogene air, but that it proceeds from the combination of the blood with the oxygene air. In the experiment I have de- fcribed, the livid colour of the venous blood in the right auricle and right ven- tricle of the heart was changed to vermi- lion. Neverthelefs it could not have loft any PRINCIPLE OF IRRITABILITY. any carbonic-hydrogene air; it only acquired oxygene. Befides, this experiment is a di- rect proof that oxygene is the principle of irritability; for by furcharging the blood with oxygene, by hyper-oxygenating it, if I may ufe the expreffion, the irritability of the blood was, as we have feen, confiderably increafed. 4. A fmall quantity of azotic air, which had been expofed for fome time to the con- tact of lime water, in order to feparate any carbonic acid air it might contain, was in- jected into the jugular vein of a dog. The animal died in twenty feconds. Upon opening the thorax, the pericardium, and the heart, the right auricle and ventricle were filled with black thick and coagulated blood. The left ventricle was of its ordi- nary colour. ■ The heart, and almoft all the mufcles, loft their irritability almoft in* tirely ; they contracted but weakly upon the application of the ftrongeft ftimuli, fuch as fulphuric asther and the electric fpark. 5. The ^4 GIRTANNER ON THE 5. The venous blood of a fheep was re- ceived in a bottle filled with azotic air. The blood coagulated in an inftant, and af- fumed a colour black as ink. There was a feparation of a great quantity of ferum. The next day, on opening the bottle, a faint fmell of ammoniac was perceivable. The air was azotic air, which extinguifhed a light. In this experiment, the azotic air in con- tact with the venous blood rendered its co- lour deeper, and even quite black. The ammoniac produced is owing to the hydro- gene air which efcaped from the venous blood, and united itfelf to the azote. The colour of the blood becoming deeper after it had loft part of the hydrogene united with it, feems to prove that this deep colour is owing to the carbon of the blood, and not to the combination of hydrogene air, as has been fuppofed. 6. A bottle full of carbonic acid air was *■ half PRINCIPLE OF IRRITABILITY. 225 half filled with the venous blood of a fheep. It coagulated in an inftant, affumed a very deep colour, and there was the feparation of a great quantity of reddim ferum. 7. A fmall quantity of carbonic acid gas was injected into the jugular vein of a dog. The animal became fleepy, and died in about a quarter of an hour. The right auricle and ventricle of the heart were filled with thick blood, and in part coagulated. The blood contained in the left ventricle and auricle was of a deeper colour than ordinary. The heart and mufcles had loft all their irritability. This experiment proves, moreover, that the deep colour of the venous blood is not owing to the combination of hydrogene air. In this experiment, part of the oxygene of the carbonic acid air probably unites itfelf with the hydrogene of the blood, and forms water, and the carbon, which before was combined with this oxygene, unites with the blood, and gives it its deep colour. 2 g &. An. 22$ GIRTANNER ON THE 8. An incifion was made in the jugular vein of a fheep, and the blood which came from it was received in a bottle full of ni- trous air. When the bottle was half filled, it was clofed. The blood coagulated im- mediately, and a feparation of a great quan- tity of blackifh ferum took place. The day after, on opening the bottle, a very ftrong fmell of nitrous aether (dulcified fpirit of nitre) was perceived ; the nitrous air hav- ing been changed in part to nitrous aether by the carbonic-hydrogene air of venous blood. This experiment proves beyond a doubt that the venous blood contains carbonic-hy- drogene air, and that this air is not very in- timately united with it, but that it feparates with the greateft eafe. The nitrous aether produced in this experiment is owing to the union of the carbonic-hydrogene air, which exhales from the blood, with the nitrous air. The blood, after it has loft this air, does not affume a vermilion colour; but, on the contrary, it takes a very deep co- lour; it is not, therefore, to the union of the PRINCIPLE OF IRRITABILITY. 227 the blood with carbonic-hydrogene, that the deep colour of the venous blood is owing, fince this colour becomes ftill deeper when the hydrogene is feparated from the blood. 9. A fmall quantity of nitrous air was injected into the jugular vein of a dog. The animal died in lefs than fix minutes. The right auricle and ventricle of the heart were filled with blood, thick, black, and partly co- agulated. The blood contained in the left ventricle of the heart, was of a much deeper colour than ordinary j the heart had loft its irritability. The lungs were of a greenifh caft, and partly putrefied*. All the canal of the wind pipe was filled with a green foam, that came in great quantities out of the mouth of the animal during the convulficns that preceded its death. Experiments upon arterial blood, 10. An incifion was made in the carotid * The green colour is a fign of nitrous acid, not of nut refaction. B. 2 G 2 arteiv 228 (SIRTANNER ON THE artery of a fheep, and the blood that iffued thence was received into a bottle full of oxygene air. The bottle, when half filled, was clofed. The colour of the blood be- came in an inftant of a bright vermilion. The next day the bottle was opened, and the oxygene gas which it contained was found mixed with a very fmall quantity of carbonic acid gas. n. The arterial blood of the carotid ar- tery of a fheep was received into a bottle full of azotic air. The bottle, being half filled, was clofed; the blood coagulated at the fame moment, and affumed a very deep colour. On opening the bottle the next day, the azotic air which it contained was found mixed with a fmall quantity of oxy- gene air, fo that a candle burnt in it for near two minutes. This experiment proves decifively, i. That arterial blood contains oxygene air. 2, The PRINCIPLE OF IRRITABILITY. 229 2. That it is to its combination with this air that its vermilion colour is owing; and that it affumes its deep colour as foon as it is deprived of its oxygene air. 12. Three ounces of vermilion blood, from the carotid artery of a fheep, were re- ceived upon a plate, which was immediately placed under a veffel filled with carbonic acid air. The blood did not change its colour, but continued the fame for fome hours. 13. Arterial blood, from the carotid ar- tery of a fheep, was received into a bottle filled with carbonic acid air. No change in the vermilion colour. Thefe two experiments prove that car- bonic acid air has no action upon arterial blood, although it has a very great one upon venous blood. 14. The arterial blood of the carotid ar- tery of a fheep was received into a bottle full 230 GIRTANNER ON THE full of nitrous air. The bottle, when half filled, was clofed. The blood contained in it coagulated immediately, and affumed a green colour upon the furface. A fmall quantity of greenifh ferum was feparated. The day after, on opening the bottle, the vapours of nitrous acid were obferved by all who were prefent. Here then is an experiment which proves, in a moft decifive manner, the prefence of oxygene in the arterial blood; fince it is from this circumftance alone that it is ca- pable of changing nitrous air into nitrous acid. The green colour, obferved in this and the 9th experiment, arifes from part of the azote feparating itfelf from the nitrous air. 15. Arterial blood, from the carotid arte- ry of a fheep, was received into a bottle full of hydrogene air, which was clofed wtien half filled. The blood became of a brighter vermilion, and remained fluid for fome time. It coagulated at laft, and a fmall quantity of ferum PRINCIPLE OF IRRITABILITY. 231 ferum was feparated. The day after, the hydrogene air contained in the bottle was found mixed with a fmall quantity of oxy- gene air, which the nitrous air abforbed. This experiment proves the prefence of oxygene air in arterial blood. 16. The arterial blood, as before, was received in a bottle containing equal portions of oxygene and hydrogene air. The bot- tle, when half filled, was clofed. The blood in the bottle became moderately hot, remained fluid, and was of a more vermi- lion colour. It coagulated at laft, and a fmall quantity of ferum was feparated. The day after, the air in the bottle was mixed with a fmall quantity of carbonic acid air, of which the prefence was afcertained by lime water. 17. A fmall glafs tube was filled with arterial blood of a bright vermilion; it was fealed hermetically, and expofed to the lieht. The blood changed its colour by 232 GIRTANNER ON THE by degrees, and in fix days became as black as venous blood. 18. The fame experiment was repeated, with this difference only, that the tube was expofed to heat, and not to the light. The blood became black in a fhorter time. The 17th and 18th experiments made by Dr. Prieftiey, and repeated afterwards, appear to me to demonftrate, that it is not to the contact with hydrogene air that the venous blood is of a black colour. I conclude from thefe experiments, 1. That the change of colour the blood undergoes during circulation is not owing to it3 combination with hydrogene air. 2. That the deep colour of the venous blood, is owing to the carbon it contains. 3. That the vermilion colour of the ar- 2 terial PRINCIPLE OF IRRITABILITY. 2,33 Serial blood proceeds from the oxygene with which the blood is combined, during its paffage through the lungs. 4. That refpiration is a procefs exactly analogous to the combuftion and oxidation of metals ; that thefe phsenomena are the fame, and to be explained in the fame manner. • 5. That during circulation, the blood lofes its oxygene, and charges itfelf with carbonic-hydrogene air, by means of a dou- ble affinity. 6. That during the diftribution of the oxygene through the fyftem, the heat which was united with this oxygene efcapes; hence the animal heat. 7. That the great capacity of the arterial blood for heat is owing to the oxygene with which it is united in the lungs. Having fhewn that the blood is oxyge- nated in its paffage through the lungs; that 2 h in; 23* GIRTANNER ON THEF7 in the circulation it lofes the oxygene it had abforbed; and that it returns to the lungs furcharged with carbottic-hydrogene air, it remains to prove* that to this oxygene, diftri- buted through every part of the fyftem, is owing the irritability and the life of orga- nized bodies. Here follow the proofs upon which this theory is founded. The irritability of organized bodies is al- ways in a direct ratio of the quantity of oxy- gene they contain. i. Every thing that increafes the quan- tity of oxygene in organized bodies, in- creafes at the fame time their irritability. We have feen a direct proof of this in the 3d experiment,»cited above. Befides this, a great number of other phaenomena fupport my opinion. The irritability of animals made to breathe oxygene air is wonderfully encreafed. Blanched plants, whofe irritability has been accumulated in confequence PRINCIPLE OF IRRITABILITY. 235 confequence of the abftraction of the fti- mulus of light, contain a great quantity of oxygene, according to the experiments of Mr. Fourcroy. 1 have obferved, in the courfe of my experiments, that plants made to grow in oxygene air become white, al- though expofed to the light. But what fhows more clearly than all, that the irri- tability is always in proportion to the quan- tity of oxygene, are the phsenomena attend- ing the action of mercury and mercurial falts upon animals. As this is one of the moft ftriking proofs of my theory, and as I have before obferved, that many perfons, and amongft the reft philofophers of the firft rank, fuch as Dr. Crawford, have been ftruck with the novelty and fimplicity of my mode of explaining thefe phamomena, I cannot forbear entering into fome detail upon this fubject. It is a well-known fact amongft phyficians, that mercury, in its metallic ftate, has no effect upon the human body. I have known many people, who for many years took a daily portion of quickfilver, to the amount of one or twro ounces, from an 2 n 2 idea 236 GIRTANNER ON THE idea of guarding themfelves from epidemic difeafes, but who never perceived any ef- fect whatever from this lingular cuftom. It is proved alfo by the experiments of Dr. Saunders, that the effects of mercurial oint- ment are owing only to the fmall quantity of mercury that has been oxidated during a long trituration. It is neceffary, therefore, that mercury fhould be oxidated, to have any effect upon the human body. On the other hand it is well known, that in perfons who have rubbed themfelves with mercurial ointment, or who have taken the oxid of mercury, the mercury, after having pro- duced its ufual effects, has paffed through the fkin in a metallic form, and has amal- gamated itfelf with watches, and the gold in the pocket, &c. The oxid of mercury, in paffing through the human body, parts with its oxygene, and it is to this oxygene alone, which remains combined with the fyftem, that the effect produced by oxidated mercury is owing, This effect is the mercurial difeafe, the fymptoms of which arc the fame as thofe of the fcurvy; the mouth. PRINCIPLE OF IRRITABILITY. 237 mouth, gums, and the ^vhole fyftem are affected in a manner extremely analogous. But the fcurvy, as I have proved in my firft effay, is a difeafe produced by the accu- mulation of the irritable principle *, The accumulation, therefore, of the oxygene producing the fame effects, the great ana- logy between the irritable principle and oxygene appears to be proved, and I think myfelf authorized to conclude, that oxygene is the principle of irritability. (M. Berthollet, in the Paris Me moires, 1780, has attributed the caufticity of me- tallic oxids to the oxygene they contain). 2. Whatever diminifhes the quantity of oxygene in organized bodies, diminifhes at the fame time their irritability. This has been fhewn in the 9th experi- ment, where the heart and the mufcles loft their irritability, having been deprived of their oxygene by nitrous air. But not to * CcmifiW erroneous. lezxc 238 GIRTANNER ON THE leave any doubt upon this fubject, I made the following experiment. Experiment 19. The heart of an animal juft killed was cut into pieces, and put into a glafs retort, to which was affixed a pneuma- tic apparatus. A very fmall degree of heat was applied to it, by means of a lamp placed under the retort. When the pieces were heated, babbles of air were perceived in the pneumatic apparatus. They remained ex- pofed to the fame degree of heat for nearly two hours, till the furface was juft burnt. Upon examining the air which had paffed into the apparatus, it was found that the firft portion of air was the atmofpheric air of the retort, mixed with a very fmall quan- tity of vital air, whofe prefence was afcer- tained by nitrous air. The fecond was vital air mixed with carbonic acid air. I have repeated this experiment upon many other parts of animals juft killed, and I have always obtained a greater or a lefs quantity of oxygene air. It is poffible to ob- tain PRINCIPLE OF IRRITABILITY. 239 tain the fame quantity of this air many times following, by expofing the animal fubftances alternately to the atmofpheric air, and to a heat of 60 or 70 degrees of Reaumur. I fhall obferve, however, that thefe experi- ments are very difficult to make, and fome time is requifite to afcertain the degree of heat neceffary to difengage the oxygene air. If the heat applied be too great, car- bonic acid air will come over inftead of oxy- gene air. It is poffible to extract all the oxygene which animal fubftances contain, by means of hot water: it is thus we make jellies. Thefe jellies are always more or lefs tranfparent, which, without any other proof, would be fufficient to authorize us to fuppofe the prefence of oxygene in jellies, becaufe it is certain that all tranfparent bodies except alcohol and aether owe their tranfparency to the oxy- gene that enters into their compofition*. I have proved, that oxygene combines with venous blood in the lungs ; that it is diftri- * This is reafoning very rapidly. Who has dete&ed oxygene in rock cryflal? buted 240 GIRTANNER ON THE buted to all parts of the fyftem by the cir- culation ; that to this principle irritability is owing: it remains only to examine what becomes of the great quantity of oxygene which all parts of the fyftem are continu- ally receiving from the blood. I fhall attempt to prove, that the different ftimu- lating fubftances abforb this oxygene. 1 have obferved in my firft effay, that there are three different flates of the or- ganized fibre. i. The ftate of health or tone of the fibre. 2. The ftate of accumulation, in which the fibre is furcharged with the irritable principle. 3. The ftate of exhauftion, in which the fibre fails through want of the irritable principle. All fubftances capable of coming in con- 2 tad PRINCIPLE OF IRRITABILITY. 241 tact with the irritable fibre, can likewife be 1. ranged under three claffes, of which The firft comprehends the fubftances which have the fame degree of affinity to the irritable principle, or the oxygene, as the organized fibre itfelf. Thefe fubftances produce no effect upon the fibre. The fecond contains thofe which have a lefs degree of affinity to the oxygene than the fibre has. Thefe fubftances, coming in contact with the fibre, will furcharge it with oxygene, and produce the ftate of ac- cumulation. Thefe fubftances may be called negative ftimuli. The third clafs contains thofe fubftances which have a greater degree of affinity to the oxygene than the fibre itfelf has. Thefe, coming in contact with the fibre,, will deprive it of its oxygene, and produce the ftate of exhauftion. I fhall call thefe fubftances pofitive ftimuli. It is a fact known at this time, that the 2 1 affinity H2 GIRtANNER ON THE affinity of different fubftances varies confi- derably according to the degree of tempera- ture. The fame variety takes place in the organized fibre. I fhall obferve, therefore, in order to be exact, that when I fpeak ge- nerally of the affinities of the irritable fibre, I mean always in the ordinary temperature of the blood of warm animals. I -will make fome obfervations upon each of thefe claffes. The firft clafs comprehends, as I have faid, fubftances having the fame degree of affinity to the oxygene as the irritable fibre. All organized, or living fubftances, are to be ranked under this clafs. (Note, The words organized and living are, in my opinion, fynonymous. I regard as living, every body, each part of any body, in a word, all or- ganized fubftances, as long as they contain the principle of irritability, or of life, and as long as the affinities are the fame as thofe of living fubftances. The wood, for inftance, of which our chairs and tables are 2 made, PRINCIPLE OF IRRITABILITY. 243 made, is an organized or living fubftance; and to fpeak properly, it cannot be faid that the wood is dead before it be rotten, and fo of the reft. Our ideas of life and death are very vao;ue ideas, and I fhall at- tempt to fix them in fome other way). Thefe fubftances produce no effect upon the irritable fibre, while their. degree of temperature is the fame as that of the fibre with which they come in contact. I have arranged, in the third clafs, the pofitive ftimuli, that is to fay, thofe fub- ftances which have a greater degree of affi- nity to the oxygene than the fibre has. Thefe fubftances, coming in contact with the fibre, combine with the oxygene it contains, deprive it of its irritability, and leave it in a ftate of exhauftion. There is a great number of thefe fubftances. The moft known are alcohol, fulfuric a?ther, opium, and other narcotics, oil of lauro- cerafus, and oils in general, greafe, fugar. AH thefe fubftances are combuftible, that. is to fay, they have a great affinity to oxy- 2 1 2 gene. 244 GIRTANNER ON THE gene, and it is by this property that they deprive the organized fibre of its irritabi- lity, by combining with the oxygene it contains. The fecond clafs comprehends the negative ftimuli, or fubftances, which have a lefs affinity to the oxygene than the fibre has. Some of the moft terrible poi- fons we know of muft be ranked under this clafs. The oxygene wThich combines with the organized fibre, when it comes in contact with thefe poifons, renders it fo extremely irritable, that the weakeft ftimulus is capable of producing death; by a law of irritability which has been explained in the firft effay. Oxygenated marine acid is for this reafon fo fatal a poifon to all organized bodies. It deftroys them by furcharging them with irritability, that is, by hyper- oxygenating them, and becomes marine acid by this operation. Arfenic, under its metallic form, has no effect upon animals; but the white oxid of this metal is one of the moft terrible poi- fons ; for it hyper-oxygenates the organized fibre PRINCIPLE OF IRRITABILITY. 245 fibre with which it comes in contact,, and re-affumes its metallic form. Oxygenated metallic falts, fuch as the corrofive or muri- atic fublimate of mercury oxygenated, &c. produce the fame effects. The oxids of filver and mercury produce greater or lefs effects upon the organized fibre, in pro- portion as they contain more or lefs oxy- gene. The black oxid of mercury, other- wife called aethiops, produces the moft trifling effects; the red oxid of the fame metal produces the moft terrible effects, and deftroys organized bodies in a very fhort time. The fame explanation applies to the action of fulfate of tin and lead, and the acetate of lead and brafs upon the organized fibre. I am convinced by experiments which I fhall relate fome other time, that the or- ganized fibre, both animal and vegetable, decompofes the water that comes in contact with it. The greateft part of the water we drink is firft decompofed, and then recompofed. It is indeed one of the means by which nature funiifhes organized bodies with 3+6 GIRTANNER ON THE with the oxygene neceffary to preferve their irritability and life. * This difcovery explains very many phaenomena hitherto inexplica- ble. I have alfo reafon to think, that by this difcovery of the decompofition of water hj organized bodies, we fhall be able to explain the moft hidden myfteries of animal phyfiology. Reflecting upon the refults of feveral of my experiments, I begin to fuppofe that the hydrogene air, which re- mains after the oxygene of the water is united to the irritable fibre, may ferve to fupply the lofs of nervous fluid, or, in other words, I fuppofe that the nervous fluid is the hydrogene air, perhaps carbon ic-hy- drogene gas. I confefs this is only a con- jecture, which 1 am not yet able to prove, but which appears to me very probable. Be this however as it may, it is very certain that water is decompofed and recompofed conti- nually in organized bodies. This is clear from experiments I fhall hereafter enume- rate. I have explained the phaenomena of hunger in animals; I have faid, that this fenfation PRINCIPLE OF IRRITABILITY. 247 fenfation was the confequence of irritabi- lity accumulated in the fyftem; and that for a fubftance to be nutritious, it muft be a pofitive ftimulus; namely, one that has a great tendency to unite itfelf to the oxy- gene, becaufe it is only by uniting itfelf with this principle, with which the fyftem is furcharged, that it can reftore the tone of the fibre, and allay the painful fenfarion of hunger. Every phenomenon fupports this theory. Different fubftances nourifh on- ly in proportion to their affinity to oxygene. Living animal fubftances (oyfters for in- ftance) afford little or no nourifhmenr, be- caufe they cannot combine with the oxy- gene, with which they are already fatu- rated; hence the common obfervation, that oyfters increafe the appetite. Animal jel- lies, fruits, vegetable fubftances in general* afford little or no nouriihment. Animal food juft killed does not nourifh fo much as that which has been kept fome time; and raw meat is not fo nourifhing as that which has been cooked. Hence all the art of cookerv, which confifts only in depriving ths, 243 GIRTANNER ON THE the food of its oxygene, by applying dif- ferent ftimulating fubftances, and, above all, the ftimulus of heat. Roafting the food is the moft fimple manner of cooking it; whilft it is expofed to the heat, it parts with its oxygene, as in the 19th experi- ment. Oils, fat, fugar, alcohol, and other fubftances, which have a great affinity to oxygene, are very nourifhing. In the Eaft: Indies, millions of men fupport themfelves by fmall quantities of opium, when the rice harveft fails them, as very frequently hap- pens in thofe wretched countries, groaning .under the defpotifm of a company of Eng- lilh merchants. Thirft is a ftate of the fyftem oppofite to that of hunger; it is a fenfation which in- dicates a ftate of exhauftion, a deficiency of oxygene. Every thing that reftores to the, fibre its loft oxygene, puts an end to this difagreeable fenfation. Water produces this effect by its decompofition when it comes in contact with the fibre. The fame effect will be produced by vegetable acids, which. PRINCIPLE OF IRRITABILITY. 249 which are always decompofed in the fto- mach of animals. It is only in proportion fo the oxygene in toe compofition of the acids, and to which they have but little affinity, that they refrefl* and allay the fen- fation of thirft. Thus vegetable acids are the beft remedies agamft the effects of nar- cotic poifons; for by their decompofition they reftore to the fibre the oxygene which the poifons had deprived it of. Vinegar, taken in large dofes, cures the ftate of ex- hauftion produced by a ftrong dofe of opium, and prevents death, which would otherwife enfue. It is well known that drunken perfons become fober by drinking a glafs of vinegar; that is, the vinegar reftores the tone of the fyftem which it had loft, by the effect of the alcohol contained in the wine. A great quantity of water produces the fame effect. Many other phaenomena may be ex- plained upon the fame principle. We find the air frefher and more agreeable after heavy rain, becaufe the watery vapours Or K which 25» GIRTANNER ON THE which rife from the earth, and come in contact with our bodies, are decompofed and reftore the loft oxygene *. The phaenomena difplayed by the rotifer, that Angular infect, which, though entirely dried up, may be re- vived by moiftening it with a drop of water, appear inexplicable; but it feems that it is eafy to account for it on my principles. The drop of water is decompofed, the oxygene it contains combines with the rotifer, re- ftores its irritability, its life, and organic motion, of which it had been deprived by the ftimulus of heat, to which it had been expofed in becoming dry. Amongft the known pofitive ftimuli, thofe which produce the greateft effects are the ftimulus of putrid fevers, or of the plague, and that of the mephitis, which exhales from putrefied animal fubftances in places where the air cannot enter, as in tombs and burial places. The affinity which this mephitic gaz has for oxygene is fo great, * Nonfenfe. The air is only become a better con- ductor of heat. that PRINCIPLE OF IRRITABILITY. a5i that as foon as it comes in contact with the fibre, it deprives it of its oxygene, and caufes death, frequently in an inftant. The beft way to prevent the fatal effects of this gaz is, to detonate nitre upon burn- ing charcoal. The oxygene gaz which e£- capes during the decompofition of the nitre fupplies the oxygene which combines with the mephitic air. This theory is fo true, that the workmen who have been fuffocated by the mephitic air exhaling from tombs have recovered their fenfes and been refrefhed (according to their own expreflion) as foon as they have been made to refpire oxygene air. I fhall hereafter relate the experiments I have made upon vegetables, with many ftimulating fubftances, but, above all, with alcohol, opium, the folution of white oxid of arfenic, vinegar, water, heat, and the oxids of mercury. I have found that thefe fubftances had effects upon plants fimilar to what they had upon animals; that the irritability of the moft irritable plants, fuch 2K2 as t$z ADDITIONAL as the mimofa and hedifarum, may be en- tirely deftroyed by pofitive ftimuli, by opium for example, alcohol, or heat; and that it is poffible to give very fenfible irritability to plants which did not appear to poffefs it, by applying, for fome time, negative ftimuli, fuch as vinegar, or white oxid of arfenic I hope that the refult of thefe experiments will be of confiderable ufe to agriculture, by {hewing us the true nature of plants, their difeafes, and the means of remedying them, I have found that oils and alcohol, employed in fmall quantities, are fpecifie remedies for the difeafes of plants, produced by the accumulation of the irritable princi- ple ; difeafes marked by the yellow colour which the leaves affume. IT is eafy to fupply the latter part of this theory with a neceffary correction. It is not credible that many pofitive ftimuli, fuch, for inftance, as the vegetable poifons of the tro- pical countries, and the venom of certain fer- pents, which produce death, in quantities fo aftonifhingly minute, fhould, as Dr. Girtan- nei OBSERVATIONS. 25J ner imagines, exhauft the irritable principle, by combining with it directly themfelves; neither, furely, can alcohol, opium, and oil of lauro-cerafus, be fuppofed to attract from the irritable fibre, if we -confider only the quantity in which they produce their effects, a large quantity of oxygene. Is it not more likely that they occafion, throughout the whole fyftem, a new com- bination of oxygene? The blood, and the mufcles of animals deftroyed by pofitive ftimuli, and of thofe deftroyed by nega- tive ftimuli, as nitre or arfenic, ought, according to this idea, to exhibit appearances diametrically oppofite. It is alfo evident, that Dr. Girtanner's, or, more properly fpeaking, Dr. Brown's, Materia Medica is too fcanty: negative ftimuli will be neceffary to correct certain aberrations of the fyftem from health. His idea of negative ftimuli, as I often obferved to Brown and his difciples in 1785 and 6, fup- plies one of the greateft defects of Brown's fyftem, It is in vain to (ay of thofe fubftan- ces 154 ADDITIONAL ces which directly, and without any appear- ance of previous excitement, in whatever quantity they are adminiftered, fuch as lead, diminifh the actions of life, that they are lefs powerful ftimuli; for how, on this principle, can they leffen the effect of the ordinary fti- muli, which are applied at the fame time ? It is equally in vain to fay (what Dr. Girtanner repeats), that the depreffing paflions are only the abftraction of the ftimuli of the exciting paflions. Univerfal experience, I apprehend, will immediately reject fuch a fcale of mental affections, as this fyftem fuppofes; a fcale which muft prefent the paflions fomewhat in this order; fuppofing the moft exciting to ftand uppermoft: ANGER, JOY, HOPE, CONTENT, {As far as the mind is capable of indif- ference. FEAR, sorrow, and fo on. Now OBSERVATIONS. 255 Now is it credible or poffible, that forrow fhould be to indifference what darknefs is to twilight ? Every individual almoft is ca- pable of judging, whether the thoughts of a perfon in affliction are lefs bufy than of an idiot ? whether the mind of one under the influence of the diftreffing paflions is lefs upon a ftretch, than of him, " Who " Whiffles as he walks for want of thought ?" During fuch a ftate of vacancy, it will hardly, I prefume, be thought that there is more mental exertion than in the moft profound forrow, even if we admit the com- mon fuppofition, that in this ftate the mind refts upon the contemplation of one or a few ideas; a fuppofition which requires much limitation. Brown very properly warns his readers of the methaphorical nature of his terms.* We * Partim ob inccrtam rei naturam, partim ob Jermonu ngefiatem, item hujus doclrbuc novitatem, incitabititas mo- tto abundare, cum filimuli parum admotum, modo deflcere, exhuuriri out confumi, c:nr, is rxhementius incubuit, pofifiv. 25* ADDITIONAL We muft therefore, without regard to them, if obfervation indicates it, admit a power in fome drugs, in fome of the paflions, and paffim deincepr dicetur. 'Turn hie, cum alias, uhique REBUS veris standum : lubrica eaufarum utpote fere incomprehenfibilium, qiutfiio, vemnatus Hit philofophie unguis, cum curd fugienda. Nequis igitur, pejr modo: re- lata dicla, tncitabilitatis naturam refpici, aut, an materia fit, et fie modo augeatur, modo imminuatur: an adharens materia facultas, nunc •vigeat, nunc langueat, definiri: aut ullo modo reconditam quafiionem altingi, quod magna fcientU mato femperferefiaElum, interpreted. 1. c I. 5. 6. Thf warning againft the enquiry concerning caufes, as being incomprehensible, requires fome explanatipn. Caufes are only phsenomena, uniformly preceding other phenomena •, they are, therefore, juft as comprehenfible as effects : we ceafe to comprehend juft where we ceafe to perceive. The bane of philofophy is the transferring of phenomena, by the imagination, from one part of nature to another, where the fenfes difcern no traces of their exiftence-, and placing them as antecedents before obferved phenomena. As this imaginary fueceflion will be wrong 999 times at leaft in icco, we fhall as often fail when we attempt, in practice, to modify the confe- quents, by regulating the fuppofed antecedents.—-But, by difcovering the real fucceffion of phaenomena, we fhall afTuredly gain infinite advantages. Thus, were oxygene the principle of irritability, we fhould not only OR S E R tf A T I O N S\ itf and in fome external circumftances, either of preventing the fyftem from giving out its excitability, or from accumulating it (which flate is very often feen, where a conti- nuance of fleep, fufficient as to its dura- tion, does not refrefh, or, according to Gullen's expreffion, render the fyftem more liable to be affected by ftimuli of all kinds), or on the contrary, of accumulating it too ra- pidly. We are even enabled, by the fore- going hypothefis,. to conceive a modus ope- randi in all thefe cafes. Thefe principles, with which the late won- derful difcoveries of Mr. Galvani, Valli, and* Volta, feem perfectly well difpofed to coa- lefce, promife all thofe advantages which would refult from a perfect knowledge of the rriechanifm of the animal functions. Was only have the fatisfa&ion of comprehending more clearly the actions of the living fyftem, but we fhould have them more in our power, than while we were ignorant of this truth. While, therefore, we religioufly abide by facts, We can do nothing fo well as invefti- gate caufe?. 2 L not Z5.& ADDITIONAL not Mayow, for inftance, infinitely nearer the truth, than any author of a later hypo- thefis, when he imputed mufcular motion to the effervefcence of his nitro-atmojpherical particles f Does not mufcular contraction or intumefcence really depend upon the com- bination of oxygene with hydrogene and azote (feparately and combined, in various proportions), in confequence of a fort of explofion produced by the nervous electri- city \ According to this hypothefis, animal motion, at leaft that of animals analogous to man, would be produced by a very beautiful pneumatic machinery; and our nervous and mufcular fyftems may be confidered as a fort of fleam-engine: This hypothefis, though not perhaps at this moment capable of ftrict proof, is extremely probable, fince it is countenanced by every obfervation and ex- periment yet made on the fubject. It ac- counts for the perpetual necefiity of inhal- ing oxygene, and enables us to trace the changes undergone by this fubftance, from the moment it is received, till the moment it is expelled. By the blood it is imparted to OBSERVATIONS. 259 to the mufcular fibres ; here, during their contraction, it combines with the elements above-mentioned into water and various falts, among which the marine and phof- phoric acids deferve particular notice. In this ftate it is taken up by the abforbents, and afterwards exhaled, or excreted. Ob- fervations, adduced in the preceding pages, fufficiently fhew the neceffity of oxygene to mufcular motion; and how the power of motion languifhes, when this principle is fcantily fupplied. It appears that meat be- comes tender in confequence of the fecondary combination of oxygene, in whatever way this fecondary combination be effected; whether by keeping it till the putrefactive procefs takes place more or lefs; by cook- ery ; by obliging the animals to "undergo violent exercife before death, as in hare- hunting, bull-baiting, and in an expedient of gluttony, rather more barbarous than either of the preceding, that of flogging poultry to death. The flefh of animals fo deftroyed ought to be more fucculent, as well as more tender. It is an obfervation 212 cf t6o ADDITIONAL of experienced fportfmen, that an hunted hare will continue to emit fleam, when brought to table, very much longer than an hare otherwife killed. I have heard the fame remark made with refpedt to hunted venifon. Thefe phenomena cor- refpond perfectly with the fuppofitiQn of liquids, partly volatile, being generated during mufcular action. In the Weft India Iflands they kill their poultry with vegetable poifon, in order to render them tender without keeping. Sti- muli, which are only lefs violent poifons, are fometimes ufed for the fame purpofe in this country. It does not appear whe- ther they produce their effect immediately, or by firft exciting the nervous electricity. But whatever be the mode of action of thefe poifons and ftimuli, that of contagious mia/mata feems to be exactly the fame.* The * I once faw an inftance, in which I could not doubt that complete intoxication was produced by the conta- gion of typhus, to which the perfon had been much expofed. One morning, immediately upon rifmg, and I knew OBSERVATIONS. 26t The Similarity of the fymptoms in typhus and fcurvy has been frequently noticed; and the fimilar fymptoms of thefe difeafes feem evidently to depend upon the fame eaiife -, the contagion of typhus depriving the fyftem of oxygene, by caufing the com- tination of a great part of that which it al- ready contains. Hence it is probable that the true indication of cure in typhus is to I knew that he had been perfectly fober the night be- fore, I was aftonilhed to obferve that flighty vivacity and difpofition to wild disjointed talk, together with the other figns that infallibly denote a certain degree of intoxication, efpecially when you are well acquainted before-hand with the manners of the party. In the courfe of the day, during which I faw him frequently, he became heavy, had febrile fhiverings, and complained of head-ache. The next day he became moire feverifh, but was not confined till the fifth day, though the head- ache and other fymptoms never quitted him. He paiTcd through all the ftages of typhus, but never feemed to be in imminent danger. In moft inftance?, the period of the excitement of the brain is not perceived \ we, hew- ever, frequently fee the action of the vafcular fyftem in- creafed at the onfet of typhus; this increafe of action fometimes mifleads practitioners into the fatal meafure of blood-letting.—Does not the highly ftline urine in fe- brile difeafes, and after exercifej depend on the chemical combinations above-mentianeJ ? reftore 262 ADDITIONAL reftore the oxygene; and it is likely that upon this principle, a certain and fpeedy cure will be contrived. The modern prac- tice, which employs ftimulants very freely, though, upon the whole, I believe, not fo mifehievous as the contrary, is not fuch as we ought by any means to acquiefce in. It does not enfure fo much fuccefs as might be expected from a method founded on juft principles; and, indeed, as far as I can learn, the different methods in ufe anfwer pretty much alike, and the difeafe is very little in the doctor's power—Oxygene may be more bene- ficial at one ftage of typhus than at another. Thofe cafes where typhus attacks per- fons after expofure to fevere cold, at a time when you cannot, by the ftricteft fcrutiny, difcover any previous veftiges of contagion in the neighbourhood, render it highly pro- bable that this difeafe may be produced by ordinary ftimuli applied to excitability much accumulated. The fymptoms of the influenza, which are fcarce diftinguifhable from thofe of catarrh, as well as the effect produced by the ftewardV vifit to the na- tives OBSERVATIONS. 263 tives of St. Kilda, (if this refptctably at- tefted though furprifing, narrative be true) afford another inftance where difeafes, extremely fimilar, at leaft, are produced by ordinary ftimuli, and by the extraor- dinary ftimulus of contagion. If the marfh-miafma be not an imaginary being, there is reafon to prefume the fame thing of intermittents, which very often appear where marfh-miafma cannot well be fup- pofed prefent. One may, I conceive, reafonably expect to remove the feverifhnefs, or indirect debi- lity, that follows intoxication, by caufing the perfon who is fuffering under it to re- fpire oxygene air. This would, perhaps, not only make up the wafle of this princi- ple, but alfo reftore the nervous electricity; a circumftance to which it will always be neceffary to attend in diforders of excite- ment, or produced by excitement. From the experiments of Mr. SaulTure and Volta, on the electrical phsenomena attending con- denfation, it may be conjectured that the animal 264 A D D I T f" d K A L animal electricity is renewed by refpiration. The want of fome Certain method of ef- fecting this will, perhaps, produce fome doubt in the reader's mind refpedting the' certain efficacy of an hyper-oxygertated at- mofphere in typhus ; but the few imper- fect trials that have hitherto been- made upon the refpiration of oxygene air, feem to me no1 more than counterbalance this doubt. The experiments of Mr. Fourcroy, the beit upon record, feem to promife the happteft fuccefs. Attention is undoubtedly not llefs' due fo the other elements of organized bodies; and if the importance of oxygene feems to have been magnified in the foregoing ob- fervations', it is only becaufe we" have few Or no facts which afford a foundation for rea- foning concerning the connection of an excefs or deficiency of hydrogene or azote With the functions of life: and yet much o'bfcurit'y and many difficulties muft be expected to remain, till we acquire the' knowledge of fuch facts. This reflection fhould render 2 11*. OBSERVATIONS. 265 us only the more attentive to the phseno- mena of life; for if we can but perceive enough to fuggeft a hew hypothefis, capable of being verified by experiments, phyfio- logy will not fail to gain fomething, and perhaps fomething confiderable, even by the proof of its falfehood. This reflection fhould alfo teach us to fet a due value on our prefent knowledge, though it be imper- fect ; and it fhould reftrain thofe rude hands that are ever ready to pluck up the tender plants of fciencej becaufe they do not bear ripe fruit at a feafon when they can only be putting forth their bloffoms. A boundlefs region of difcovery feems to be opening before us. Fhyfical fcience, which began with remote objects, now promifes to unfold to us the more difficult- and more interefting knowledge of our- felves. This kind of knowledge will af- furedly, as Dr« Girta'nner obferves, become a part, and the moft important part, of edu- cation ; and it will effect a greater improve- ment in the morals of mankind, than all the ?. m fermons 266 ADDITIONAL fcrmons that ever have been, or ever will be preached. I'hyfiological ignorance is the moft abundant fource of our fufferings ; every perfon accuftomed to the fick, muft have heard them deplore their ignorance of the neceffary confequences of thofe practices, by which their health has been deftroyed ; and when men fhall be deeply convinced, that the eternal laws of nature have connected pain and decrepitude with one mode of life, and health and vigour with another, they will avoid the former, and adhere to the latter. And as actions are named immoral from their effects, felf-love and morality are fo far perfectly the fame. Nor is this fort of morality likely to terminate in itfelf; but the habit of acting with confideration, and upon principle, will extend from the felfifh to the focial actions, and regulate the whole of life. If it be faid, that the general rules of health have long been deduced from univer- fal experience, it may be anfwered, that the difference between the perception of two events, OBSERVATIONS. 267 events, which, though feemingly allied, are placed at a great diftance from each other, with a blank between them, and a dif- tinct view of the whole fucceffion of ope- rations that infeparably connect them, is immenfe. In the former cafe, there will feem to be room for the caprice of chance to intervene and feparate them ; in the fe- cond, there cannot be room for any fuch de- lufivc expectation; and this more particu- lar information will render it much more difficult for a perfon to impofe upon his own underftanding, than it has hitherto been. It has always, indeed, appeared to me an effential requifite in a tolerably conftituted feminary of knowledge, to provide the means of popular information on the means of preferving health; but peculiar advan- tage may now be expefted from fuch an in- ftitution. Its extreme imperfedion has hi- therto rendered medicine a particular craft, little worth fludying, but for the money it would bring. A medley of error, non- m 2 fenfe ?6$ ADDITIONAL &c. fenfe, and contradiction, was not likely 'a engage volunteer fludents ; for nothing is more intolerable to moft minds, than to lie toflipg upon a fea of doubt. At prefent there is beginning to appear, in phyfiology and pathology, fomething like the fimpli- city and certainty of truth. In proportion as the laws of animal nature come to be af- certained, the fludy will be gradually ef- teemed more worthy of general attention, and in fpite of the difguft raifed by anatomy at firft, it will finally prove the moft popu- lar, as being the moft curious and intereft- ing, branch of philofophy ; and a New Me- dicine will at length arife, with healing on her wings, from the afhesofthe Old ADDENDA. AD D E N D A. r~| i I HE following is the paffage of the Flora Laptonica alluded to at page 58. It were to be wifhed that the few pages of incidental obferva- tions, occurring in that work, were printed fepa- rately. In fpite of much quaintnefs of language • and puerility of fentiment, they would intereft many readers, not likely to meet with them in their prefent fituation :— Ofe/ix Lappa ! qui in ultimo angulo mundific be- ne lates contentus et inmcens. Tu nee times annonts charitatem, nee Mar lis pmlia, qua ad or as tuas per- venire nequeunt,fed fiorentifiimas Europe provincial et urbes, unico momento, fapc dcjiciunt, delcnt. Tu dor mis hie fub tuapelle ab omnibus curis, contenthw^ bus, rixis liber, ignorans quid fit invidia. Tu nulla nofci nifi tonantis Jovis fidmina. Tu duels innocentif fimos tuos annos ultra ccntenariuni numcrmn cumfaciii fenectute etfummdfanil ate. Te latent myriades mork- rum nobis Europms communes. Tu vivis in fyhisy avis infkar, nee fementemfacis, nee metis, tamen alit te Deus optimus optime. Tua ornamsntafunt tremula arborum folia, graminofique luci. Turn potus aqua crytlallinapelluciditatis, qua nee cerebrum infanid ad- fcit, nee firumas in Alpibus His producit. Cibus tuus efi vet verno tempore pifcis recens, vsl aftivo ferum laclis, vel autumnali tetrao, vcl hiemali, cam recens. rangiferina abfque fale et pane, finguld -vice unico confians ferado, cdis, dumfecurm s leclofurgu, 27» ADDEND A. dumque eum petis, nee nofii venena nofira, qua latent fub didci melli. Te non obridt fcorbutus, necfebris intermittens, nee obejitas, nee podagra, fibrofo gaude's corpore et alacri, animoquc libero. 0 fancla innocen- tia, efine hie tuus thronus inter Faunos in fummo feptentrione, inque vilifftmd habitd terra ? numnefic prafers firagula hac betulina mollibus ferico teclis plumis £ Sic etiam credidere veteres, nee male. HAPPENING, in a company where the Reve- rend Mr. Lellie was prefent, to mention my opinion of the poffible good effects of air, containing lefs ox- ygene* than common, in confumption, he related fome circumftances relative to the academy at Liege, which he thought gave fome countenance to my idea; and afterwards favoured me, at my requefl, with the following particulars :— Cum a me, vir eruditiffime, pollutes ut charta ea commendem qua nuper in familiari colloquio afferui circa modum procedendi cum adolefcentibus in academid Anglorum Leodii in Germanid, cum morbo vulgo diclo confumptione vel febri hectica laborarent, hoc eo lubentius facto, quod exinde ope principiorum artis me- dica forfitan poteris aliqua deducere qua humano ge- neriplurimum proderunt. Notandam imprimis academiam ill am, in qua ego ipfe per plures annos habitavi,in vertice alti montispro- pe arc em civitatis Leodienfis effefitam, et aerem ibi eflfe tampurumutin eo moniales Angla, qua prope acade- miam ADDENDA. miam olim habitabant, ut plurimum pulmonum con- fumptione vitam amiferint, et ob illam caufam in infimd urbisparte, prope Mofamflumen, in denfo aere domici- liumfixerint, ubi raro confumptione labor ant. Exinde partim et ex aliis obfervationibus mos invaluit in aca- demid, adolefcentes confumptionelabor antes adloca in* fima, nebulofa, et paludofaFlandria Auflriaca mitt ere, Brugas puta. Antwerpiam, vet Gandavum, ubi ope denfioris aeris intra paucos menfesfanitatemfermefem- per recuperabant; fiver o adacademiamredibant, ite- rum in eundem morbum incidebant. Si cut verb in men- tem venerit dubitare an confumptione proprie dicld la- bor-averint,' ex fequentibus fymptomatibus five indiciis poterit ferre judicium. Laborabant initio morbitufft ferme continud, deinde fputafanguinolenta mittebant, turn purulent a et foetida, macilentiores quotidie evade- bant, pallidus illis erat ut plurimum vultus,fed inter- dumfubito rofeo colore dififufus, oculi ut plurimum vi- vidi et acuti. Hac pauca currente calamo,Jine terminorum tech- nicorum ornatu confcripfi ; fedfi crudus hie fcribendi modus difpliceat, nihil vetat quominus poffis ea, non mutato fenfu, in meliorem formam redigere. Vive, vale, vir docliflime, et epifiold hdc, fiquid prodejfe point, rutere. C. LESLIE. Osonii, die 70 5^/. anni 1792, THE ADDEND A. THL following conjecture concerning the ufe and effect of manure, is part of a paper read before the Chemical Society at Edinburgh, April 7, 1786, and printed in that very excellent mifcellany, the Edinburgh Magazine, for one of the two following months. The theory advanced in it ftill appears to me, fo far as it goes, to be juft, and as it is fo much akin to the fpeculations contained in the preceding pages, I have fubjoined it here.— The refult of Dr. Ingenfioufz's experiments on vegetables expofed to the light of the fun is well known. Since the publication of hisEnglifhwork, he has been more or lefs conflantly employed on the fame fubject; and on occafion of fome controverfies, lias publifhed both in French and German many ex- periments, all tending to the fame conclufion. His chief controverfy was with Mr. Senebier of Ge- neva, which, however, has terminated completely in his favour, for his antagonifl has publicly ac- knowledged that he was totally milled by fome in- attention in conducting his proceffes. I find too in the Acta Thcddoro-Paktina (Vol. V. 1784,) a very long feries of experiments-by Profeffor'Sue- cow of Mannheim, which exactly coincide with thofe of Dr. Ingenhoufz. He concludes his account of them in the follow- ing manner. ' Thofe effects of the folar light on plants, which Dr. Ingenhoufz firft fo admirably pointed out, are confirmed by the preceding expe- riments, in which trees and plants appeared moil capable of yielding pure air in the light of the fun ; whereas in the made they afforded air more or lefs phlogi.licated. That the air which is extricated when ADDENDA. *,3 when vegetables are expofed in water to the fun^ fhine, proceeds from their leaves and other pares, fcarce needs any proof. Water indeed does con- tain a quantity of air which is difengaged by the influence of light; but the quantity is' fo fearing even in a large quantity of water, that it can by no means be fet in competition with that which vegetables yield in the courfe of a few hours. Did this air proceed from the water, it would in very few cafes prove fo pure, unlefs the water contained fome of the green conferva ; but then it would be to this mofs that the origin of the air muft be afcribed. The difference in the air itfelf which vegetables yield when other circumilances are alike, puts it be- yond all doubt, that the air mull proceed, not from the water, but the vegetables.' I mall leave the fociety to judge how many negative refults will be requifite to deflroy the force of thefe numerous ex- periments, and proceed to what I have more par- ticularly in view. Dr. Ingenhoufz, in his laft work, (Verm. Schr.p, 394.) has related fome variations of his experi- ments. He found that water impregnated with acids, alkalis, neutral falts, exprefled juices of vegetables, as of raifins, peaches, &c. very much promoted the production of pure air by vegetables, except in the cafe of the graffes (of which the product is variable from undifcovered caufes), of the conferva rivularis, and water-plants in general, which are killed by fixed air, and fome others, when this acid is employed. The dirTer* race is fo ftriking that it will be proper to felect iomc instances. *-4 ADDENDA. Quantity. Quality. ?*. cubic inches of a triplex lacini- ^ Q ata m common water ... 3 220 --------------in ftrongly aerated water . . . . Si 286 but .i was fixed air from the water. 3 cubic inches of yew, , - 4 2 06 .-----------—in aerated water 19 244 of which the pure air was 12 2 cubic inches of grafs in 86 of common water . . . 5 280 -------in 86 of aerated water . 13 336 N. B. * was fixed air. 2 cubic inches of yew in com- mon water . . . 2^ 225 —------------in aerated water 20 322 | fixed air. * In 6 hours of pretty fair weather. i • • i r ' Quantity of Fixed Onallfr- 3 cubic inches or yew in 120 pure Air. Air. ^HaiIT* of common water . i\ o 234 Ditto with the addition of 2 cubic inches of muft . 5 a little 270 with 2 of peach juice 5 a little 292 with 2 of ripe apple . 34 4 250' with $0 drops of aqua- fortis . . . 44- 4 250 * * 6 hours of bright fun-fhine. 3 cubic inches of grafs in 86 cubic inches of water . 4 o 248 r 2 cubic ADDENDA. 2 75 Quantity of Fixed ~ ,. ' 2 cubic inches of grafs with pure Air- Air- • ^ '' 1 cubic inch of mull • . 91 a little 312 Ditto of ripe cucumber juice . . 2-j- a little 230 40 drops of vitriolic acid 74 £ 295 a little vitriolated tartar 12 1. 296 * * * fine fun-ihine, 6 hours. 2 cubic inches of fempervi- vum tectorium in 86 of water ... 3 fcarce any 24^ Ditto with 1 cubic inch of its own juice . . . 43. o 308 * * * * fine weather, 6 hours. 2 cubic inches of grafs in 86 of water ... 3 fcarce any 245 Ditto with 1 cubic inch of ftrong vinegar 74 £ 276 with 1 of juice of the cornus mafcula . 8j 4 323 1 of juice of onion 2-j \ 228 1 of juice of turnep 2-j. i 217 In thefe numerous inftances, the effect of the ad- dition equally appears from the numbers that ex- prefs the quantity and thofe that exprefs the quality of the air produced. It may be obferved alfo, that a few fubftances, fuch as the juice of onions, cu- cumbers, and turneps, prevent, inftead of forward- in?, the extrication of air, and that it is of an in- ferior quality to that which is produced when no addition is made. 1 n 2- In l]6 A D D E N D A. In the firft place it is evident, that among the fubitances which favour the extrication of pure air, we have every thing which can well be fup- pofed to enter into the compofition of manure, falls fimple and compound, with the juices and extrac- tive matter of plants. If we may likewife affume, that the production of this falutary fluid is a natu- ral function and an healthy procefs, it follows di- rectly, that the ufe of manure is to occafion a great- er exertion of that function. That the production * of dephlogilticated air is among the chief functions of vegetables is a fuppo- fition countenanced by many experiments. Mr. Cavendifh himfelf infers, that the vital air obtained by Dr. Ingenhoufz comes from the decompofition oi water. There is one experiment related by the kit-mentioned author, highly remarkable, and not to be explained on any other fuppofition that has .been hitherto thrown out. ' I boiled, (fays he I.e. p. 198. B. 2.) fome water for two hours, and then poured it boiling into a glafs balloon of the c.ipr,city of 200 cubic inches. The balloon was *hen carefully clofed. Before the v/ater was grown quite cold, I introduced into the balloon four cubic inches of granulated green matter, which was taken out of the great refer voir in the botanic garden fat Vienna), and repeatedly warned in boiling water ; care being taken to fqueeze out after each warning r.!l the moifture, in order that none except boiling water might remain adhering to it. I next clofed the balloon with a perforated flopple, in order to allow the water an exit when it mould be preffed by the air evolved from the green matter. The balloon u.;s inverted intci-a vefiel of quickfilver placed in the ADDENDA. 271 the fun. The air generated at firft was abforbed by the wrater itfelf: but being foon faturated, it re- fufed to talce up any more ; and in the courfe of a few days I found a confiderable quantity of air collected.' If it then be true that water is decom- pounded by vegetables, it follows that inflammable air is abforbed and fixed ; an opinion countenanced by Prieflley's experiments of charcoal, on fliced roots of onions, &c. for neither he nor Senebier, nor Ingenhoufz, nor I think any other, has ever found inflammable air in the elaftic fluid afforded by the leaves and other proper parts of vegetables expofed to the fun. The inflammable matter which furrounds certain vegetables is, 1 fuppofe, an ef- fential oil in the ftate of vapour ; and if any plant fhould yield inflammable air in the way I have men- tioned, I doubt not but it would furnifh, in other refpects as well as in this, a Angular exception to the refl of the kingdom. There is ftill another corollary more precife and Satisfactory to be drawn from thefe premifes. The quantity of dephlogiilicated air that is extricated, will afford a teft of the quantity of food taken in by the plant. It may, moreover, be fuppofed, that the addi- tions, which Dr. Ingenhoufz made ufe of, are not thofe which will produce the greateft effect. It is. reafonable to fuppofe, that Nature in the immen- sity of her ftores, has ftimulants far exceeding thefe in power; which further inquiry will both difcover and teach how to apply. For if thefe principles be juft, they will be eafily applicable, when we are in poffeffiou of a greater number of facts, both to gardening 278 ADDENDA. gardening and agriculture : And I doubt not but that in time a rational fyftem of vegetable medi- cine may be conflructed, if the fubject be properly profecuted. In the mean time, languiihing trees may be wafhed dr fprinkled with water acidulated with vitriolic acid, which Ingenhoufz found to be moft effectual in promoting the production of pure air. It will not be difficult for any perfon who may choofe to reflect on the fubject, to contrive other experiments, by which thefe principles may be con- firmed to refuted. THE END. POSTSCRIPT. I KNOW how much Millman infifts upon the crafTa- mentum, obferved by fome authors infcorbutic blood. But in fuch a cafe I think a very few negative more than coun- terbalance thoufands of pofitive tcftimonies, where no ac- count is given of circumftances, and no attention has been probably paid to them: the very mode of blood-letting, the time it ftands before it is examined, the temperature in which it is kept, &c. may affect the combination of blood with oxygene, and by confequence, its coagulation. It is perhaps, in the prefent improved ftate of chemiftry, practicable to afcertain the laws of the coagulation of the blood : M. Parmentier and Deyeux, have not indeed perfectly fucceeded in their refearches on milk, a very li- milar fluid. It is remarkable, that in their experiments the heat of boiling water would not crudle or produce a fkin upon milk without theprefence of air, and yet thatit fhould have been indifferent what kind of air was prefent. N. B. I have lately attended to the colour of phthifical blood ; and in fome inftances where it was juft drawn, I have preceived both tht florid and claret or purple colour > the former is diftindtly feen, when the blood is fpread thin, the latter, when it has a confiderable depth. This will ex- plain the apparent contradiction in p. 124. ;L7 0 "Aiyiij-^VrV" yy ■ W'--v ■ *$£l':'*'■ •'■■*:' ''■ <' ■\,*v .-■■' : SJiXipi' ■ ' ■ • ' - '• ' k'l^S>:-^-----;----:';;.-.'--'- ^^xevu'v-,;- ;. fS>iv: &#&>•..