152 ORIGIN OF THE BILE. 



same products by the action of acids and of alkalies. 

 This, however, 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 

 preexistence of ammonia and taurine in the bile must 

 be doubted, and because we have no reason 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 purpose, but we are utterly 

 ignorant how these elements enter into these combina- 

 tions, or what is the chemical character of the nitro- 

 genized compound which unites with the elements of 

 starch to form bile, or rather choleic acid. 



61. Choleic acid may be formed from the elements 

 of starch with those of uric acid and urea, or of allan- 

 toine, or of uric acid, or of alloxan, or of oxalic acid 

 and ammonia, or of hippuric acid. The possibility of 

 its being produced from so great a variety of nitrogen- 

 ized compounds is sufficient to show, that all the nitro- 

 genized products of the metamorphosis of the tissues 

 may be employed in the formation of bile, while we 

 cannot tell in what precise 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 on by the 

 same reagents. Yet we cannot, from the similarity of 

 the products, conclude that these two compounds have 

 a similar constitution. In like manner the nature of 



