33 QN THE SEBACIC ACID. 



dccompofition of a certain portion of fulphuric acid by the fat, 



or of the carbone of the acetous acid difengaged from its 



combination. 



His fccond by In following the fecond procefs defcribed by Crell, we do 



gavc^munatic 11 not °^' tim an . v acetous acid, but an acid, which is nothing elfc 



acid, but the muriatic. In fact, it forms with the nitrate of fiiver 



a precipitate infoluble in an excefs of nitric acid ; with foda it 



yields cubic cryllals. If we pour fulphuric acid upon thcfe 



cryitals, a penetrating gas is difengaged, which, on being 



brought into contact with the air, gives rife to vapours : the 



fame acid, mixed with nitric acid, diflblves gold. With the 



oxide of mercury it forms a volatile fait; with potafh it forms 



a fait capable of being fufed without undergoing decompoii- 



tion. Thefe circumftances render it probable that Crell has 



employed the potafh of commerce, which always contains mu- 



But if well per- riate of potafh ; for in repeating this procefs with pure potafh, 



formed, vinegar. nQ ac id j s obtained, except an almoft imperceptible quantity 



of vinegar. This vinegar is formed by treating the fat with 



potalh and the fulphuric acid ; for fat contains no acid, not 



even when it is rancid. At leaft, I have feveral times treated 



rancid fat with water, and have uniformly obtained a liquid, 



which did not redden the tincture of Tournefol. 



E. Recapitulation. 

 Enumeration THESE experiments prove, in my opinion, what I have 



o? d thrXve f ° n advanced in the beginning of this memoir ; namely, that there 

 refults. exifts in the product of diftiiled fat a peculiar acid, which, in- 



ftead of being volatile, odorous, fuffocating, is on the con- 

 trary folid, inodorous, and fixed to a certain degree ; that, 

 betides this acid, the product of diftiiled fat contains acetous 

 acid ; that the febacic acid, has no fliare in producing the 

 fmell of diftiiled flit, which probably depends upon fome par- 

 ticles of fat, converted into vapour and altered in their nature^ 

 They prove, betides, that by the procefles of Crell, and by 

 that defcribed in the chemiftry of Dijon, we obtain only the 

 muriatic or the acetous acid ; that confequently the febacic 

 acid has hitherto remained unknown, and that in the prcfent 

 ftate of our knowledge it is a new acid. 

 Hog's lard only I ought to mention, that all the experiments which I have 

 related have been made with hog's lard, and that I have not, 

 like Crell, varied thefu experiments with human fat, the 



marrow 



was ofed. 



