1818.] their Combinations with Alkalies. 199 



and by the potash and lime, which proceed from the decompo- 

 sition of certain salts. Two suggestions are offered by the 

 author, which seem to result from his conclusions, although 

 they are in opposition to the opinions generally received on this 

 subject, and which he proposes to make the subject of a future 

 memoir. He asks, whether fat is not the only animal matter 

 which is capable of being converted into the peculiar adipose 

 matter, and not the muscular fibre? and must not this change 

 be effected by alkalies, and not, as is generally supposed, by 

 nitric acid? 



The author concludes by giving a summary view of the differ- 

 ences between the three bodies which have obtained the name 

 of adipocire. The biliary calculus and spermaceti may be con- 

 sidered as immediate simple principles, since we have not been 

 able to separate any bodies from them, without changing their 

 nature. But this is not the case with adipocire, properly so 

 called, as this certainly results from the action of two fatty 

 bodies, one of which has the greatest analogy with margarine, 

 while the other is very similar to the fluid fat. Biliary calculus 

 requires for its fusion a temperature of 278°, whilst spermaceti 

 melts at 112°. The fatty matter from dead bodies melts at 

 different temperatures, from 111 to 129°, according to the pro- 

 portions of the substances that enter into its composition. One 

 hundred parts of boiling alcohol dissolve 18 parts of biliary 

 calculus, and 6*9 parts of spermaceti : adipocire appears to 

 dissolve in it in an indefinite quantity. 



Potash boiled during 15 days with biliary calculus in the 

 proportion of five to one does not saponify it. The same alkali 

 boiled with spermaceti during five days in the proportion of 18 

 to 30 entirely saponifies it. A substance is then produced ana- 

 logous to margarine, but which differs from it so decidedly in 

 some respects, that they may be considered as forming two 

 distinct species. If the difficulty of saponifying biliary calculus 

 does not depend entirely upon its force of cohesion ; if, for 

 example, we should prove that it cannot be effected by exposing 

 it in a digester to a temperature of above 280°, we must conclude 

 .that the proportion of the elements of biliary calculus does not 

 admit of its being reduced into the state of a body which has a 

 great affinity for alkalies. The difficulty which there is in sapo- 

 nifying spermaceti shows that the elements of it are not in the 

 same relation as those of fat ; and what proves the same thing is, 

 that spermaceti does not produce the sweet principle of oils, as is 

 ;the case with fat. 



(To be continued.) 



