208 TEXT-BOOK OF PHYSIOLOGY. 



believed that in the intestine it in some way prevents or 

 factive^changes in the food. ^^There can be no doubt that if the bile 

 be prevented from entering the intestine there is an increase in the 

 formation of gases and other products which impart to the feces 

 certain characteristics which are indicative of putrefaction. As to 

 the manner in which bile retards this process nothing definite can be 



Bile has been supposed to be a stimulant to the peristaltic move- 

 ments of the intestine, inasmuch as"tKese~mo vemenfs " diminish when 

 one is diverted rrom the intestine. 



Though no definite nor specific action on any of the different 

 classes of food principles can be attributed to the bile, there is abun- 

 dant evidence to show that its presence in the alimentary canal during 

 digestion is essential to the maintenance of the nutrition of the body. 

 That the bile as a whole, or at least part of its constituents, favorably 

 influences digestion and general nutrition is evident from the 

 phenomena which follow its total exclusion from the intestine, as 

 when the common bile-duct is ligated and a fistula of the gall-bladder 

 is established. The following phenomena were observed in a young 

 dog so prepared by Professor Flint. During the first five days 

 succeeding the operation the abdomen was tumid and there was 

 some rumbling in the bowels. Though the animal ate every day, the 

 discharge of fecal matter became infrequent, the matter passed being 

 grayish in color and highly offensive. After two weeks the alvine 

 discharges took place three and four times daily. For four days the 

 weight remained normal; afterward it began to diminish, and from 

 this time the animal continued to lose strength and weight until its 

 death, thirty-eight days after the operation. Ten days after the oper- 

 ation the appetite, which had been very good, increased, but did 

 not become ravenous until a few days before death. The animal 

 usually ate from a pound to a pound and a half of beef-heart daily, 

 always refusing fat. There was an absence at all times of jaundice, 

 fetor of the breath, and falling of the hair. Postmortem examination 

 showed that the bile-duct was obliterated, and there was no evidence 

 that any bile could have passed into the intestine. The results of this 

 and similar cases go to show that that portion of the bile which is 

 secretory in character is essential to digestion and the nutrition of 

 the body that, though large quantities of food are consumed, pro- 

 gressive diminution of weight takes place until nearly 40 per cent, of 

 the body is consumed. In some instances the breath becomes fetid 

 and there is a falling of the hair, showing some profound disturbance 

 ot the general nutritive process. 



Intestinal Peristalsis. During digestion the walls of the in- 



line exhibit a series of contractions which, beginning at the pylorus, 



run along the canal to its termination in the large intestine. These 



