DIGESTION. 205 



Human bile obtained from an accidental biliary fistula was shown 

 by Jacobson to contain the following ingredients, viz. : 



COMPOSITION OF HUMAN BILE. 



Water, 977-4 



Sodium glycocholate, 9.94 



Cholesterin, 0.54 



Free fat, o.io 



Sodium palmitate and stearate, 1.36 



Lecithin, 0.04 



Other organic matters, 2.26 



Sodium chlorid, 5.45 



Potassium chlorid, 0.28 



Sodium phosphate, 1.33 



Calcium phosphate, 0.37 



Sodium carbonate, 0.93 



In this analysis the solid ingredients constitute 22.5 parts per 1000, 

 of which two- thirds are organic and one- third inorganic. The 

 amount of solids varies according to the animal from which the bile 

 is obtained. 



Sodium Glycocholate and Taurocholate. Of the various in- 

 gredients of the bile none are more important than these two salts, 

 usually known as the bile salts. The sodium glycocholate is found 

 most abundantly in the bile of herbivora, the sodium taurocholate 

 in the bile of the carnivora. These salts are compounds of sodium 

 and glycocholic and taurocholic acids. When separated from the 

 sodium, the acids will crystallize in the form of fine acicular needles. 

 Under the influence of hydrating agents, such as dilute acids and 

 alkalies, both acids will undergo cleavage into their respective com- 

 ponents e. g., glycocoll and cholalic acid, taurine and cholalic acid. 

 Glycocoll and taurine are crystallizable nitrogenized compounds 

 known chemically as amido-acetic and amido-isothionic acids re- 

 spectively. The bile salts are produced in the liver by a true act 

 of secretion, as they are not found in any of the tissues and fluids of 

 the body. After being discharged into the intestine they undergo 

 chemic changes, after which they can no longer be recognized. In 

 all probability they are reabsorbed into the blood and play some 

 ulterior part in the nutrition of the body. 



Cholesterin. Cholesterin is a constant ingredient of bile, though 

 it is not confined to this fluid, as its presence has been determined in 

 the crystalline lens, blood-corpuscles, nerve-tissue, and various patho- 

 logic fluids. It is an organic non-nitrogenized substance resembling 

 the fats in some particulars, but differing from them in not being 

 capable of saponification with alkalies. It presents itself in the form 

 of thin transparent rectangular crystals, insoluble in water but soluble 



