336 DIGESTION. 



through the portal vein to the liver at this time, and that 

 this blood contains some of the materials of the food 

 absorbed from the stomach and intestines, which may need 

 to be excreted, either temporality, to be re-absorbed, or 

 permanently. 



Respecting the functions discharged by the bile in 

 digestion, there is little doubt that it assists in emulsifying 

 the fatty portions of the food, and thus rendering them 

 capable of being absorbed by the lacteals. For it has 

 appeared in some experiments in which the common bile- 

 duct was tied, that although the process of digestion in the 

 stomach was unaffected, chyle was no longer well-formed ; 

 the contents of the lacteals consisting of clear, colourless 

 fluid, instead of being opaque and white, as they ordinarily 

 are, after feeding. (2.) It is probable, also, from the re- 

 sult of some experiments by Wistinghausen and Hoffmann, 

 that the moistening of the mucous membrane of the in- 

 testines by bile may facilitate absorption of fatty matters 

 through it. 



(3.) The bile, like the gastric fluid, has a strongly 

 antiseptic power, and may serve to prevent the decompo- 

 sition of food during the time of its sojourn in the intes- 

 tines. The experiments of Tiedemann and Gmelin show 

 that the contents of the intestines are much more foetid 

 after the common bile-duct has been tied than at other 

 times ; and the experiments of Bidder and Schmidt on 

 animals with an artificial biliary fistula, confirm this ob- 

 servation ; moreover, it is found that the mixture of bile 

 with a fermenting fluid stops or spoils the process of fer- 

 mentation. 



(4.) The bile has also been considered to act as a kind 

 of natural purgative, by promoting an increased secretion 

 of the intestinal glands, and by stimulating the intestines 

 to the propulsion of their contents. This view receives 

 support from the constipation which ordinarily exists in 

 jaundice, from the diarrhoea which accompanies excessive 



