THE BILE. 145 



Man Ox 



(hepatic bile). (bladder-bile). 



Sodium chloride 65.16 7.50 l 



Potassium chloride 3.39 



Sodium carbonate 11.16 2.50 



Trisodium phosphate 15.90 



Tricalcium phosphate 4.44 40.0 



Calcium carbonate 9.50 



Potassium sulphate variable 



Sodium sulphate 25.0 



Iron, Silica 1 traceg traces 



Magnesium, copper J 



The Mucinous Body of the Biles. 



The mucinous body which is found in the bladder-bile of all 

 animals is apparently of a different nature in different animals. The 

 mucus of the human bile thus largely consists of true mucin, while 

 in ox-bile a mucinous nucleo-albumin is principally found. To 

 isolate this latter, the bile is precipitated with 5 times its volume 

 of absolute alcohol and immediately centrifugalized. The super- 

 natant liquid is poured off, and the sediment rapidly dried with 

 filter-paper and dissolved in water. By repeating this process the 

 substance can be obtained in a fairly pure form. Its character as 

 a nucleo-albumin becomes apparent on treating its neutral solutions 

 with a small amount of hydrochloric acid. A flocculent precipitate 

 then develops, which readily dissolves upon the further addition of 

 hydrochloric acid to the extent of 0.3 per cent. This solution re- 

 mains clear for a long time even when kept at the temperature of 

 the body. If a small amount of pepsin, however, is added, a sepa- 

 ration of nuclein occurs. On fusing the dried substance, moreover, 

 with potassium hydrate and sodium nitrate, an amount of phosphoric 

 acid is obtained which is greatly in excess of the amount required 

 to saturate all of the mineral ash that is present when calculated as 

 tricalcium phosphate. On boiling with a dilute mineral acid no 

 reducing-substance is formed, as in the case of true mucin. Acetic 

 acid precipitates the substance from its solutions, in the absence of 

 biliary acids ; but this precipitate, unlike that of mucin, is soluble 

 in an excess of the acid. 



The mucin proper \vhich is found in human bile may be isolated, 

 as already described (page 113). 



The Biliary Acids. 



The biliary acids which are normally found only in the bile are 

 essentially compound amido-acids, which are formed through the 

 union of glycocoll on the one hand, and taurin on the other, with a 

 cholalic acid. In the bile of sharks Hammarsten discovered the ex- 

 istence of a third group of biliary acids, which are rich in sulphur, 

 and, like the conjugate sulphates of the urine, yield sulphuric acid 



1 This figure is too low, owing to the fart that Hoppe-Seyler's analysis has reference to the 

 inorganic salts, which were not dissolved by alcohol. 



10 



