METAMORPHOSES OF BILE. 129 



26. 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 



Formula of choleic acid = C 76 N 2 H 66 O 22 



subtract 



2 eq. carbonic acid = C 2 O 4 > r- ivr u r 

 2 eq. ammonia = N 2 H 6 j = C N " 



Remains the formula of cholic 

 acid = C 74 H 60 18 (31) 



When we consider the very close coincidence be- 

 tween these formulae and the actual results of analysis 

 (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 proportion of 

 its elements, no matter in how many different forms 

 they may be united to produce that acid. 



27. Let us now add the half of the numbers which 

 represent the formula of choleic acid, to the elements 

 of the urine of serpents, that is, to neutral urate of 

 ammonia, as follows : 



the formula of choleic acid . . . . = C 38 N H 33 O U 



Add to this 



1 eq. uric acid . . . = C 10 N 4 H 4 O 6 > p, N H n 



1 eq. ammonia . . . = N H 3 5 ~ 



The sum is = C 48 N 6 H 40 O 17 



28. But this last formula expresses the composition 

 of blood, with the addition of 1 eq. oxygen and 1 eq. 

 water. 



