322 DIGESTION. 



Functions of the Liver. 



The Secretion of Bile is the most obvious, and one of the 

 chief functions which the liver has to perform ; but, as 

 will be presently shown, it is not the only one ; for im- 

 portant changes are effected in certain constituents of the 

 blood in its transit through this gland, whereby they are 

 rendered more fit for their subsequent purposes in the 

 animal economy. 



The Bile. 



Composition of the Bile. The bile is a somewhat viscid 

 fluid, of a yellow or greenish-yellow colour, a strongly 

 bitter taste, and when fresh with a scarcely perceptible 

 odour ; it has a neutral or slightly alkaline reaction, and 

 its specific gravity is about 1020. Its colour and degree 

 of consistence vary much, apparently independent of 

 disease ; but, as a rule, it becomes gradually more deeply 

 coloured and thicker as it advances along its ducts, or 

 when it remains long in the gall-bladder, wherein, at 

 the same time, it becomes more viscid and ropy, of a 

 darker colour, and more bitter taste, mainly from its 

 greater degree of concentration, on account of partial 

 absorption of its water, but partly also from being mixed 

 with mucus. 



The following analysis is by Frerichs : 



Composition of Human Bile. 



"Water 859-2 



Solids 140-8 



I,000'0 



a, small branch of an interlobular hepatic duct ; 6, smallest biliary 

 ducts ; c, portions of the cellular part of the lobule in which the cells 

 are seen within tubes which communicate with the finest ducts. 



