INCOME OF MATTER 97 



by the liver, and the pancreatic juice, secreted 

 by a gland similar in structure to the 

 salivary glands, called the pancreas. The 

 bile is constantly being formed by the liver, 

 and passes drop by drop from the end of the 

 bile-duct into the duodenum. This fluid 

 does not take an active part in the digestion 

 of the constituents of food, and it may be re- 

 garded more as an excretion or waste product 

 of the complicated chemical processes occur- 

 ring in the liver. Still, as it is poured 

 into the small bowel so near its beginning, 

 it must exert some influence. That influence 

 may or may not be beneficial according to its 

 quantity. If in great amount it may pass back 

 into the stomach and partly arrest the digestive 

 process there, as happens in a bilious attack ; 

 or it may to some extent interfere with 

 processes in the bowel if in excessive amount, 

 and it appears to act as a stimulant 

 to the musculo-nervous mechanism of the 

 bowel by which the chyme is propelled on- 

 wards. In excess it may cause diarrhoea. 

 A portion of the bile may be stored in the 

 gall bladder, an organ, however, that does not 



