ANIMAL MATTEK. g^J. 



• After feparating the greafe, and filtring the liquor, the re* 

 fidue was fubmitted to the following experiments. 



To boiling water it gave a yellow colour, and the property 

 oF reddening vegetable blues: After wafhing in feveral wa- 

 ters, it continued to turn the colour, though it ceafed to give 

 acidity. VVafliing rendered its colour deeper than at firft; 

 aiid when ditTufed in a little water, it ftill reddened paper of 

 turnfol. 



Its folution in alcalis was of a deep blood colour. It was 

 precipitated by acids in yellow flakes. 



This matter feels fat and pitchy; has a rancid fmell, and The fibrous 

 %ery bitter tafte. matter refembles 



The fufion and fweliing which it undergoes when placed on 

 hot coals, the greafy vapour, and fetid colour, produced by 

 this operation; the fmall quantity of coal which it leaves, 

 fliews its refemblance to fat fubftances, notwilhftanding its 

 acidity. 



. Sect. 2. On a clofer inveftigation of the yellow matter^ 

 the following charafteriftics and properties were obferved : 



It fo faturated alcalis as nearly to ma(k their properties, — Itfaturatsi 

 Its combinations with potafli and ammonia lathered like foap alkalis, 

 and water, and are not decompofad by carbonic acid, but 

 precipitated the foiutioiis of mercury and lead in yellowiih 

 white flakes. 



The yellow matter decompofed alcaline carbonates, in the Decompofes car- 

 cold, with efFervefcence, and likewife the acetate of potafli, ''O"*^*' 

 with the afliftance of water, and a gentle heal. 



The authors of the memoir next made ufe of alcohol, and It is a yellow 



found that the yellow matter was compoled of a fmall quan- .. ^"^ 

 f r T matter, 



lity of fat, which was taken up by the alcohol; and of an 

 3cid, which, on account of its colour, they denominated 

 ** yelloxv acid." This acid, when deprived of its fat, which 

 occafions an alteration in its properties, was of a deeper co- 

 lour, more readily reddened the paper of turnfol, did not 

 melt in the fame manner as before, nor exhale the fame rancid 

 fmell, but fetid and ammoniacal vapours. • 



The yellow acid is diflblved in the fat, to which it com- The yellow !i. 

 municated acidity and rancidnefs. It combined with ammo- ^"°'' ". ?" ^"'* 

 nia, and deprived it of its fmell ; and by diflillation it yielded fifting of a2ote, 

 all the products of animal fubftances. Its conftituent princi- hydrogen, car- 

 pies, therefore, are azote, hydrogen, carbon, and oxigen; and 

 it muft be placed among animal acids* 



, Sect. 3. 



