METAMORPHOSES OF BILE. 135 



If now we subtract from the elements of choleic 

 acid, the products formed by the action of muriatic 

 acid, namely, ammonia and taurine, we obtain the 

 empirical formula of choloidic acid. Thus: from the 



Formula of choleic acid ............ G^NgH^s 



Subtract 

 1 atom taurine ......... C 4 NH 7 O 1 



1 eq. ammonia ......... NH 3 



There remains the formula of cho- 



loidic acid .; ...................... = C n H 5 A 2 (30) 



27. Again, if from the formula of choleic acid 

 we subtract the elements of urea and 2 atoms of 

 water ( 2 eq. carbonic acid and 2 eq. ammonia), 

 there will remain the formula and composition of 

 cholic acid. Thus ; from the 



10 ~1 

 J = : C 4 



Formula of choleic acid = 



subtract 



2 eq. carbonic acid = Cj O 4 ~l _ 

 2 eq. ammonia = N 2 H 6 j 



Remains the formula of cholic acid = C 74 H^O^ (31) 



When we consider the very close coincidence be- 

 tween these formulae and the actual results of ana- 

 lysis (see Appendix, 29, 30, 31), it is scarcely possible 

 to doubt that the formula above adopted for choleic 

 acid expresses, as accurately as is to be expected in 

 the analysis of such compounds, the relative propor- 

 tion of its elements, no matter in how many differ- 

 ent forms they may be united to produce that acid. 



28. Let us now add the half of the numbers 

 which represent the formula of choleic acid, to the 



