160 ORIGIN OF THE BILE. 



formed, in bile, we should obtain the same products 

 by the action of acids and of alkalies. This, how- 

 ever, is contrary to experience. 



Thus, even if we could convert allantoine, or uric 

 acid and urea, into taurine and ammonia, out of the 

 body, we should acquire no additional insight into 

 the true theory of the formation of bile, just because 

 the pre-existence of ammonia and taurine in the 

 bile must be doubted, and because we have no rea- 

 son to believe that urea or allantoine, as such, are 

 employed by the organism in the production of bile. 

 We can prove that their elements serve this pur- 

 pose, but we are utterly ignorant how these ele- 

 ments enter into these combinations, or what is the 

 chemical character of the nitrogenised compound 

 which unites with the elements of starch to form 

 bile, or rather choleic acid. 



62. Choleic acid may be formed from the ele- 

 ments of starch with those of uric acid and urea, or 

 of allantoine, or of uric acid, or of alloxan, or of ox- 

 alic acid and ammonia, or of hippuric acid. The 

 possibility of its being produced from so great a va- 

 riety of nitrogenised compounds is sufficient to 

 shew that all the nitrogenised products of the meta- 

 morphosis of the tissues may be employed in the 

 formation of bile, while we cannot tell in what pre- 

 cise way they are so employed. 



By the action of caustic alkalies allantoine may 

 be resolved into oxalic acid and ammonia ; the 

 same products are obtained when oxamide is acted 



