80 Memoir upon Animal Fat. 
which liberated acetic acid upon treating it by the sulphurie 
acid *, 
The precipitate formed by the acetate of Jead in the wash- 
ing of oxygenated fat, is nothing else but the fat itself com- 
bined with oxide of lead, and which carries with it a little 
mucous acid; the former floats above, when the precipitate 
is decomposed by the sulphuric acid. 
Oxygenated fat being very soluble in alcohol, a great 
part of it may be precipitated by water. By the energetic 
action of the concentrated nitric acid upon fat, there is a 
notable quantity of nitrate of ammonia formed, of which 
we may be convinced by mixing potash or quicklime with 
the washings. 
Oxygenated Muriatic Acid.—The action of this acid upon 
fat not having been yet described, I think it may be useful 
to enter into some details. 
I passed a great quantity of oxymuriatic acid gas into fat 
kept in fusion in B. M., the gas, before arriving at it, pass- 
ing through a vessel containing water. The fat absorbed a 
very great quantity of it. 1 continued to pass it until the 
bubbles no longer arose. i 
After cooling, the fat was considerably augmented in 
weight; its whiteness became dirty, and its consistence was 
entirely changed; it was soft, resembled an oily thick h- 
quid, which might be easily poured from one flask to the 
other, even at the temperature of 10°'(50° Fabr.): in the 
air, white vapours of acid are disengaged at the commence- 
ment. 
Having left it nearly two months in the air, it resumed a 
little more solidity, but never that of common fat, much 
less that of oxygenated fat: its taste was rancid, not sensi- 
bly acid, leaving behind it a slightly bitter taste, which 
burns the throat. The simple muriatic acid is so combined » 
with fat, that by washings in boiling water I only took off 
a very small quantity of it. The nitric acid disengages the 
above acid from it in abundance, with effervescence and 
* Rancid fat, and very old suet, also furnished me with acetic acid upon 
treating them in this manner. 
white 
