CHOLIC ACID. 119 



acid, and at 290 it becomes converted into dyslysin (Strecker*) ; 

 when inflamed it burns with a clear flame. It dissolves in sulphuric 

 acid ; and if to this solution we add a drop of syrup (1 part of sugar 

 to 4 of water), the fluid assumes a beautiful purple-violet tint. If 

 cholic acid be boiled for some time with hydrochloric acid it ceases 

 to be crystallisable, and is converted into the resinous choloidic 

 acid; and on further prolonging the boiling,, the body, at the same 

 time that it loses its solubility in alcohol and alkalies, also parts 

 with its acid properties and then forms dyslysin. By the action of 

 boiling nitric acid, it is for the most part converted into capric, 

 caprylic, and cholesteric acids, without yielding oxalic acid or the 

 volatile acids of the first group. 



Composition. This acid, which was first obtained in a state of 

 purity by Demarcay, has been recently examined with much care 

 by Strecker.f He found that it was constituted in accordance with 

 the above formula. It consequently consists of : 



Carbon 48atoms .... 70'588 



Hydrogen 39 .... 9'559 



Oxygen 9 .... 17'647 



Water 1 .... 2-206 



100-000 



Consequently the atomic weight of the hypothetical anhydrous 

 acids =4987*5, and its saturating capacity = 2-005. 



Mulder,! from his analyses of this acid, has deduced for it the 

 the formula, C 50 H 36 O 6 4-5HO. 



Strecker, who by his admirable memoir on the bile of the ox, 

 has done so much to advance our knowledge regarding this very 

 obscure fluid, has unfortunately increased the existing confusion 

 regarding cholic acid by giving it the new name of cholalic acid, 

 while he applies the name of cholic acid to another acid which we 

 shall subsequently describe. It is, however, true that Gmelin 

 applied the term cholic acid to that acid of the bile in whose salts 

 he recognized a sweet taste, and regarded it as a nitrogenous acid ; 

 but the non-nitrogenous acid first obtained in a state of purity by 

 Demarcay, which in its mode of preparation and in its properties 

 is identical with that which is here described, has so long been 

 known as cholic acid that this name ought to be retained, and the 

 more so because the new name of cholalic acid is by no means 



* Ann. d. Ch. u. Pharra. Bd. 58, S. 375-378. 



t Ibid. Bd. 66, S. 1-61. 



| Unters. ub. d. Galle, ubers. v. Vdlkel., Frank, a. M. 1847. 6. 26. 



