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No. XV. 

 Memoir on the Analyjis of Black Vomit. By Dr. Isaac 



CaTHRxVLL. 



Read June 'T"^ HE invefligatloii of the properties of fecre- 

 zoth, 1800. JL ted fluids has long engaged the attention of 

 the phyfiologift and chemift : but, their enquiries have 

 generally been dire£ted to a knowledge of thofe fluids in 

 a healthy ftate, while little notice has been taken of the 

 fecretions of fome of the moft important vifcera after a 

 ftate of difeafe. The caufe of this deficiency, in the ex- 

 amination of morbid fecretions, and particularly in that 

 denominated the black vomit, mufi: be afcribed to the 

 danger fuppofed to attend fuch an undertaking ; though 

 moft obfervers muft have been ftruck with the Angular 

 appearance of this difcharge, and much aftoniflied with 

 the fpeedy diflblution that enfued ; yet, none that I have 

 had an opportunity of confulting, have attempted an 

 analyfis of this fluid. When I firft contemplated an ex- 

 amination of the black vomit, in 1793 and 1794, I 

 confidered it as an hazardous undertaking, and limited 

 my views merely to diftinguifh that fluid from putrid 

 bile ; but, after fubjedling it to many experiments, and 

 finding that it had no effecl on my health, I have been 

 enabled to advance one ftep farther in the enquiry ; and, 

 I have now the fatisfadiion of fubmitting to the Philofo- 

 phical Society, an analyfis of that fluid, together with its 

 effedts, when applied to the healthy fyftem. 



Defcription of the Black Vomit. 



The black matter, or vomit, fo called, appears to be of 



two kinds. One, confining of a number of black flaky 



Vol. V. R particles, 



