482 B1LIFUSCIN. 



together with biliprasin and a brown, humus-like body, 

 biiihumin. It is first treated with alcohol, in which 

 only biliprasin dissolves with a beautiful green color, 

 and the bilirubin is then extracted by means of boiling 

 chloroform. 



Bilirubin, C 16 H 18 K 2 3 (or C 9 H 9 E"0 2 ). Dark-red crys- 

 tals, of the color of chromic acid. In an amorphous 

 state, as obtained by precipitating it from its solution 

 in chloroform by means of alcohol, an orange-red 

 powder. Fuses when heated and is decomposed, swell- 

 ing up at the same time. Insoluble in water, very 

 slightly in alcohol and ether, more easily in chloro- 

 form, benzene, and carbon bisulphide. It dissolves in 

 alkalies very easily, forming a deep orange-red liquid, 

 which, on the addition of a great deal of water, be- 

 comes a pure yellow, and, even in very dilute condition, 

 colors the skin yellow. Hydrochloric acid precipitates 

 the bilirubin from this solution. When calcium or 

 barium chloride or lead acetate or other metallic salts 

 are added to a weakly ammoniacal solution of bilirubin, 

 dark-brown colored, fiocculent precipitates separate, 

 which are the metallic compounds (salts) of bilirubin. 

 When an alkaline solution of bilirubin is mixed with 

 commercial nitric acid (containing hyponitric acid), 

 the yellow solution becomes first green, then blue, 

 violet, ruby-red, and, finally, a dirty-yellow; especially 

 do these changes of color take place when alcohol is 

 previously added. 



Biliverdin, C 16 H 20 E" 2 6 (or C 8 H 9 ^0 2 ). Is produced 

 when the solution of bilirubin in caustic soda, is 

 shaken with air or boiled. It then becomes green, and, 

 on the addition of hydrochloric acid, biliverdin is de- 

 posited. Lively green precipitate; insoluble in water, 

 ether, and chloroform, easily soluble in alcohol. With 

 nitric acid it gives the same reaction as bilirubin. 



Bilifuscin, C 16 H 20 K 2 4 . Is contained in biliary cal- 

 culi only in very small quantity. In order to obtain 

 it in a pure condition, its alcoholic solution (see above) 



