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Show 12 Of An so RPTIO N general/y. Of A a :30R1‘TIO N generally. tion, is found in greater quantity at one time than another. This increase of quantity is evidently connected with greater force in the heart and arte- rics, propelling the fluids, as we see after violent exercise. Now these facts correspond better with the theory which supposes organized orifices, or that the mouths of the cxhalent arteries terminate on surfaces; for, as the force is greater which propels the fltiids, these orifices must be in proportion distended; and the fluid being also propelled with greater velocity, we can easily conceive how the secretion should be encrcased. On the other hand, that (copious cold sweat which takes place on fainting, appears to depend on the greater relaxation ofthese exhalent orifices permitting the fluids to escape : but on the principle of transudation, which must suppose the fluid and liltre to be almost always in the same state, these phaenomena are absolutely mm INQUW ten inexplicable. That the oil is fluid in the living body, I allow; but that it transudes, I deny. It is contained in cells, from whence it cannot escape but by the mouths of absorbent vessels; accordingly, it cannot be squeezed from one part to another, butmaintains invariably certain f‘lXCd situations iti all bodies where it is to be found. Supposing oil capable of transuding in the living body, then it would follow that the most dependant parts of the body would ultimately contain it in the greatest quantity, as gravity would naturally lead it that way, unless the whole of those cells were so full of oily and wa- tery fluids, that the lesser specific gravity ofthe oil should carry it to the top: another consequence would he, that no part of the body could possibly be exempt from oil. But as we know that neither of these circumstances are true, the transttdation of oil becomes more than improbable. Haller, I ob- serve, adduces, asa proof ofthe transudation of oil, the circumstance of its giving transparency to the surfaces of dead bones, and even appearing on these surfaces in a liquid form. But, besides that this is an instance in the dead body, I'laller was not aware, that, in orderto this transttdation, which I allow, some circumstances are necessary, which can never exist in the living body: in the first place, the cells containing the fat must be previously broke down by putrclaction; secondly, the watery fluids must evaporate, and the bones become dry. "m l vr‘ tdatio Ilat taeic v' n throu is no transt ~ ‘ e, I am perfec gh the cuticl tly Certal‘-n. ‘t'csieations "' '""""‘r~-Mv-s-~«rrwr Mrmmwm: . z. 13 Vesications from burns or blisters afford us an opportunity of being con\ ineed of this fact. The fluid tnay sometimes be absorbed by the vessels on the surface ofthe skin, and may thus be suspected to have transuded through, the cuticle; but more commonly it remains days or weeks, or till it is let out by the surgeon‘s scissars. Even in the dead body, where transttdation of watery fluids so generally takes place, there is no transttdation through the cuticle. I have kept aportion ofthe dead body, covered with the skin and cuticle, before the fire, for six weeks together; it was as little dried as the first moment it was placed there,- whcreas, in one hour, had the cuticle been removed, the skin would have become hard, transparent, and horny. In short, the intention.ofnature is just the reverse of what Galen and Professor Mckcl imagine; it is to prevent the evaporation ofsuch fluids as are in the cellular membrane, and are immediately iti contact with the cuticle; for if these evaporate, the cells of the Cellular membrane communicating fre ' with one another all over the body, they would he succeeded by fluids behind, and thus an immense waste offluids would take place. For the same reason, Nature covers oranges, lemons, and fruit in general, with an analogous membrane: it is equally line, and has this property at least of the human cuticle, ofprt'venting transttdation ofccllular fluids. livery one may convince himself of this fact: by removing this membrane, the fluids quickly evaporate, and the fruit becomes shrivelled and dried. In short, nothingT appears to me more evident than this fact, that in the living body there is no transttdation of watery fluids: could it take place, there would be no suCh disease as a pretcrnatural Collection of fluid in any cavity, no such disease as dropsy; for the fluids transuding through membranes and cuticle, must pass from one cavity into another; from the thorax, in the hydro}: p ‘Jn/is, into the subjaccnt abdomen, and having there. formed ast‘fft's, would soon transudc and form writ/1m of the lower extremities, where, likewise, after some little time, it would transude through the cutiele, and these diseases would naturally cure themselves at last. hit (\ery body knows, that water may remain long collected in the chest, without producing dropsy of the belly; and this last I have known exist years, without producing swellings ofthc legs, 'tVlicn swelliugs ofthe legs lime taken place, I l‘me seen the cutis distended, and shining, and hard, for many \\ eelvs, |