ACTION OF THE BILE IN DIGESTION. 253 



Disregarding slight variations in this table, which may be accidental, it 

 may be stated, in general terms, that the bile begins to increase in quantity 

 immediately after eating ; that its flow is at its maximum from the second to 

 the eighth hour, during which time the quantity does not vary to any great 

 extent ; after the eighth hour it begins to diminish, and from the twelfth 

 hour to the time of feeding it is at its minimum. 



One of the uses which has been ascribed to the bile is that of regulating 

 the peristaltic movements of the small intestine and of preventing putrefac- 

 tive changes in the intestinal contents and the abnormal development of gas ; 

 but observations on this point have been somewhat conflicting. During the 

 first few days of the experiment just described, the dejections were very rare ; 

 but they afterward became regular, and at one time there was even a tend- 

 ency to diarrhoea. There can be little doubt, however, that the bile retards 

 the putrefaction of the contents of the intestinal canal, particularly when 

 animal food has been taken. The fasces in the dog with biliary fistula were 

 always extremely offensive. Bidder and Schmidt found this to be the case 

 in dogs fed entirely on meat ; but the faeces were nearly odorless when the 

 animals were fed on bread alone. In the case of intestinal fistula in the 

 human subject (Busell), the evacuations which took place after the intro- 

 duction of alimentary substances into the lower portion of the intestine had 

 an unnaturally offensive and putrid odor. In this case, as it was impossible 

 for matters to pass from the portions of the intestine above the fistula to 

 those below, the food introduced into the lower opening was completely 

 removed from the action of the bile. 



It has been shown that the bile of itself has little action upon any of the 

 different classes of alimentary substances. In the faeces of animals with 

 biliary fistula, the only peculiarity which has been observed, aside from the , 

 putrefactive odor and the absence of the coloring matter of the bile, has been 

 the presence of an abnormal proportion of fat. This was observed in the 

 faeces of a patient suffering under jaundice apparently due to temporary ob- 

 struction of the bile-duct (Flint). The fact was also noted in the dogs 

 experimented upon by Bidder and Schmidt. 



The various experiments which have been performed upon animals render 

 it almost certain that the bile has an important influence, either upon the 

 digestion or upon the absorption of fats. Bidder and Schmidt noted, in ani- 

 mals with biliary fistula, that the chyle contained very much less fat than in 

 health. In an animal with a fistula and the bile-duct obliterated, the pro- 

 portion of fat was 1'90 parts to 1,000 parts of chyle ; while in an animal 

 with the biliary passages intact, the proportion was 32'79 parts per 1,000. 

 In animals operated upon in this way there is frequently a great distaste for 

 fatty articles of food. In the observation made in 1861 the dog refused fat 

 meat, even when very hungry and when lean meat was taken with avidity. 



Experiments on animals, with regard to the influence of the bile upon 



the absorption of fats, have resulted in hardly anything definite. It is 



known, however, that when the bile is diverted from the intestine, the 



quantity of fat in the chyle is greatly reduced and a large proportion of 



18 



