INTEGUMENTS. 



■months, and tbe urine in the cold : the former was in greater fore, before putting on tliis drefs, and immediately after leav- 

 quantity during five months, and the latter during fevcn. ing it, tlie total lofs by ihepulmonaryand ciitaneousdif. barges 

 The largelt proportion of urine was 143 oz. which occurred was afcertained. The amount of the lofs by the lun^^s was 

 in the month of Ueceraber ; and of the perfpiration 1300Z. known by weighinir the fubjeft of experi?iient juft before 

 in Sep'.ember. The average daily amount of the food, on he put on the drcfs, and again immediately before he re- 

 a mean of experiments continued for a year, was 27,1802. ; moved it. Wl\en the latter quantity was fubtraded from 

 of the drink 102,17 ; of the urine 64,84; of the perfpi- the total lofs, the remainder gave the value of the cuta- 

 ration 60,10 ; of the feces 4,35'. The ingefta were to the ncous difcharge. From repeated trials performed in tliis 

 •urine, throughout ihe whole year, as 2,03 to i : but at manner, Seguin and Lavoificr found the mean lofs, by the 

 •many particular times they were as 3 to 2 ; their ratio to cutaneous and pulmonary exhalations, to be aboiit iSgr. 

 the perfpiration as 2,18 to i ; to the fecal difcharge as in the minute, or 2 lb. 130Z. in 34 hours. The pulmonary' 

 30,13 to I ; and the perfpiration of the whole year to the difcharge amounted to 15 oz. ; fo that there remains i lb. 

 urine as i to 1,08. Thefe experiments differ from thofe of 140Z. as the mean quantity of daily perfpiration. 

 SanAorius and of Rye, in (hewing that the urine exceeds The greateil quantity of matter perfpired in a minute 

 tlie perfpiration even in a hot climate. was 26,25 gr. troy ; and the minimum 9 gr. The quantity 



It appears doubtful, fays Haller, on comparing together perfpired is increafed by drink, but not by folid food, 

 the re'fults of the trials made by individuals of different Perfpiration is at its minimum during meals, and im.mediately 

 ages in various climates and feafons, whether the difcharge after : it reaches its maximum during digeition. Memoires 

 by the (kin exceeds that by the uri:ie. On fu<jR a com- de I'Acad. des Sciences, 1790 ; or in Fourcroy, Syft. des 

 parifon we mu'.t fet down the cutaneous exhalation much Connoi(r. Chimiqiies, feci. 8, ord. 3. 



below the quantity afligncd by Sandorius, as it did not Our next objeft of inquiry is into the compofition and 

 exceed 60 oz in a. very hot climate, and in colder countries properties of the cutaneous exhalation. As it efcapes from 

 was 56, 45, or even 30 oz. the furface infenfibly, there is a difficuhy in collefling it in 



It will be readily perceived, as we have already obferved, fuflicient quantity for examination : hence its nature and 

 that thefe cjlculations 'do not give the meafure of the per- compofition are very imperfectly known. Lifter, who col- 

 •fpiration alone, but of the cutaneous and pulmonary dif- letted it by placing his hand in a glafs, found it to be water 

 charges together. To feparate thefe, and to determine the with a faltifh or urinous tafte. 



■quantity of each, ItiU remained an important problem. The fluid colleded by Mr. Cruikfliank appeared to pof- 

 the folution of whicli has been attempted only of late fefs all the properties of pure w,\t ?r. When Mr. Aberne- 

 years. thy had procured 3 dr. of fluid, he evaporated one half : 



Mr. Cruikfhank introduced his hand into a glafs jar, and there remained on the glafs a fmall refiduum, which had a 

 tied a bladder, lixed to the :!iouth of the jar, round his wrift. very flight tafte of fait. The other half was fuffered to 

 In iefs than a minute the infide of the bottle was rendered ftand many days, in which time no chai'ge appeared. It 

 dim, as if it had beeiv held over the fteam of warm water : did not alter the colour of vegetable blue ; no coagulation 

 fmall diops appeared in Iefs than ten minutes, and a tea- or precipitation of animal matter was produced by muri- 

 fpoonful of tranfparent and perfectly infipid fluid, weighing atic acid, neither was any change caufed by the addition 

 30 gr., was collected in an hour. AlFuiriing that the h.^nd of pure alkali. It appeared, therefore, to Mr. Abernethy, 

 is to the whole body as i to 60, and that the who!e furface that the v;ater of perfpiration contains httle of any thing, 

 perfpires equally, the exhalation at this rate would be 71b. except a very fmall portion of fait. 



6 oz. in 24 iiours. When the experiment was repeated after We cannot reafonably doubt that the greater part of the 

 taking exercife, 48 gr. were collefted in an hour, which matter of perfpiration is water ; but it certainly contains 

 is at the rate of 12 lb in 24 hours. By breathing into a other matters, of which the nature is not well afcertained. 

 bottle for an hour, this gentleman collected 124 gr. of I:s fenfible properties are often very perceptible: it caufes 

 infipid tranfparent fluid : the produce in 24 hours at this the peculiar odour of the body, which is very remarkable 

 rate would be 6 oz. i dr. 36 gr. If this be added to the in particular individuals, and poflefTes peculiar charaders in 

 former llattment of the c'.itaneous exhalation, the fum will be whole races of mankind. Its fmel is often four ; and it is 

 81b. I dr. 36 gr.; and the evaporation from the lungs will faid, under fuch circumftances, to ciiange the vegetable blue 

 be little more than •-th of the whole. Bichat fays that he colours to red. Berthollet thought he had dacfted the 

 colledied 2 oz. of fluid by breathing for an hour into a prefence of the phofphoric acid ; he obferved that a blue 

 veffel. Anat. Gener. t. 2, p. 70X. paper, applied to a part labouring under a gouty paroxyfni, 



Mr. Abernethy collected from his hafid and wrift, inclofed became red ; but Fourcroy remaiks, that if this acid were 

 in a glafs jar for fix hours, about 3 dr. of fluid. He efti- conftantly fccreted, it mull accumulate on the ikin, as it is 

 mated the furface from which this was colleCled at 4-th of too fixed to be volatilized with the aqueous vapour of per- 

 the whole body : hence, if the perfpiration be equal at all fpiration. 



times and in all parts, the produce in one day would be From' the ftrong odour of the perfpiration when profufe, 

 about Zr. lb. This reftdt is fo different from that of Mr. and from the tinge which it communicates to linen, there is 

 Cruikfhank, that there muft be fome fignal error in the data reafon to fuppofe that it contains a particular animal matter. 

 on one fide or the other. In the perfpiration of the horfe, an animal lubliance tff the 



The method adopted by Lavoifier and Seguin feems cal- nature of urea has been dctcficd by Fourcroy and Vauque- 

 eulated to aftbrd refults more worthy of our confidence, lin, who have alfo difcovered that the phofphatc of lime is 

 The whole body was iiiclofed in a filk bag, varnitlied with left in confiderable quantity by the evaporation of the per- 

 elaftic gum, impenetrable by air or moillure, haring a fmall fpircd matter on the f1<in of the fame animal. It feems to 

 opening carefully cemented round the mouth through which cryft^alhze on the furface, and forms the branny matter de- 

 the perfon might breathe ; fo that whatever came from the tached by friction of the furface. The above-mentioned 

 lungs efcaped, while the whole of the cutaneous difcharge chemiils obferve that the urine of this aniiiial contains no 

 was confined within the bag. By weighing the body, there- calcareous phofphatc. 



Vol. XIX. Gg Mr. 



