ANALYSIS OF BLACK VOMIT. 119 



Tiding to the bottom of the vefiel, than the flaky fub- 

 ftance. There were fome dilproportions between the 

 yellow-coloured fluid, and the quantity of flaky fub- 

 itance, as in the other appearance of the vomit. The 

 flaky matter was very readily re-incorporated with the 

 yellow-coloured fluid, by the leaf! agitation of the velTel j 

 and, when kept in a phial, corked for eight or ten days, 

 affiimed rather an agreeable faccharine odour, and was 

 extremely brifk, like fermenting beer. This laft pro- 

 perty is not peculiar to this fluid, but common to fome 

 other animal fecretions. When the black vomit was 

 kept for two years in a ftate of reft, the flaky particles 

 became perfedly feparated. On agitating the veffel, the 

 former was immediately incorporated with the latter ; 

 and, after remaining at reft fix months, ihowed fcarce 

 any difpofition to feparate. This was the appearance, if 

 1 recoiled:, accurately, of the black vomit, exhibited by 

 Dr. Monro, of Edinburgh, to his clafs, in 1792, and 

 which had been lent to him from the Weft-Indies : yet, 

 as the profefl~or did not permit it to go out of his hand, 

 1 cannot fpeak correfily as to the fa£t ; but, believe it was 

 not feparated, and coniiiled of a turbid black-coloured 

 fluid. 



The mucus-matter which was fometimes vomited in 

 the yellow fever, and particularly in that which appear- 

 ed in lyg", was very ropy, and of a black colour. 

 This matter floated on a fluid of a dark colour, which 

 appeared to receive its tinge from the colouring-matter 

 of the mucus. When this matter was agitated in a phi- 

 al, the mucus fliowed no difpofition to mix with the 

 rtuid-part of the vomit, and, when it was repeatedly 

 v.'ailied, in clear water, became nearly of the colour of 

 the mucus fecveted in the alimentary cana'l. This black 

 matter was difcharged in large quantities, in the cafes 

 which proved mortal in 1 797, and was a very in- 



R 2 adive 



