176 THE BILE. 



COMPOSITION OF Ox BILE. 



Water 888.00 



Glyko-cholate of soua I 90 00 



Tauro-cholate " " I 



Biliverdine 1 



Fats I 1342 



Oleates, margarates, and stearates of soda and potassa 



Cholesterin .......... J 



Chloride of sodium 1 



Phosphate of soda ........ 



" " lime }> 15.24 



" " magnesia 



Carbonates of soda and potassa ...... J 



Mucus of the gall-bladder 1.34 



1000.00 



BILIVERDINE. Of the above mentioned ingredients, biliverdine 

 is peculiar to the bile, and therefore important, though not pre- 

 sent in large quantity. This is the coloring matter of the bile. 

 It is, like the other coloring matters, an uncrystallizable organic 

 substance, containing nitrogen, and yielding to ultimate analysis a 

 small quantity of iron. It exists in such small quantity in the bile 

 that its exact proportion has never been determined. It is formed, 

 so far as can be ascertained, in the substance of the liver, and does 

 not pre-exist in the blood. It may, however, be reabsorbed in 

 cases of biliary obstruction, when it circulates with the blood and 

 stains nearly all the tissues and fluids of the body, of a peculiar 

 lemon yellow color. This is the symptom which is characteristic 

 of jaundice. 



CHOLESTERIN (C 25 H 22 0). This is a crystallizable substance which 

 resembles the fats in many respects ; since it is destitute of nitrogen, 

 readily inflammable, soluble in alcohol and ether, and entirely in- 

 soluble in water. It is not saponifiable, however, by the action of 

 the alkalies, and is distinguished on this account from the ordinary 

 fatty substances. It occurs, in a crystalline form, mixed with color- 

 ing matter, as an abundant ingredient in most biliary calculi ; and 

 is found also in different regions of the body, forming a part of 

 various morbid deposits. We have met with it in the fluid of 

 hydrocele, and in the interior of many encysted tumors. The 

 crystals of cholesterin (Fig. 46) have the form of very thin, color- 

 less, transparent, rhomboidal plates, portions of which are often 

 cut out by lines of cleavage parallel to the sides of the crystal. 

 They frequently occur deposited in layers, in which the outlines of 



