148 STARCH, &c. CONTRIBUTE TO THE 



when heated in the air, like resin, yields ammoniacal 

 products, and when treated with acids, yields taurine 

 and the products of the decomposition of choleic 

 acid ; when acted on by alkalies, it yields ammonia 

 and cJiolic acid. At all events, the sugar of bile 

 contains nitrogen, and much less oxygen than starch 

 or sugar, but more oxygen than the oily acids. 

 When, in the metamorphosis of sugar of bile or 

 choleic acid by alkalies, we cause the separation of 

 the nitrogen, we obtain a crystallized acid, very 

 similar to the oily acids (cholic acid), and capable 

 of forming with bases salts, which have the general 

 characters of soaps. Nay, we may even consider 

 the chief constituents of the bile, sugar of bile and 

 choleic acid, as compounds of oily acids with organic 

 oxides, like the fat oils, and only differing from 

 these in containing no oxide of glycerule. Choleic 

 acid, for example, may be viewed as a comjDound of 

 choloidic acid with allantoine and water : 



Choloidic acid. Allantoine. Water. Choleic acid. 



^72^0,0,, + C^N^HsOg + H7O7 = C,eNoH6e022 



Or as a compound of cholic acid, urea, and water : 



Cholic acid. Urea. Water. Choleic acid. 

 C74H60O18 + C^N.H.O, + H,0. = C^eN^HeeO^^ 



46. If, in point of fact, as can hardly be doubted, 

 the elements of such substances as starchy sugar, 

 &c., take part in the production of bile in the 

 organism of the herbivora, there is nothing opposed 

 to such a view in the composition of the chief 



