232 UNCONSCIOUS NERVOUS OPERATIONS 



alkaline medium, affects the proteids more rapidly and 

 more powerfully than pepsin, and so digests those which 

 were not sufficiently changed by the gastric juice. 



Another ferment in the pancreatic juice acts like the 

 saliva upon starch, converting it into malt sugar, but its 

 action is far more powerful. This ferment is not present 

 in the pancreatic juice of infants, and they are therefore 

 unable to digest starchy foods properly. 



The pancreatic juice has two different effects upon the 

 fats, they having hitherto been unchanged. The first 

 effect is to separate them into exceedingly small particles, 

 which can pass through the walls of the intestine, that is, 

 the juice forms an emulsion with the fat. The second 

 effect is a chemical decomposition of fat into fatty acid 

 and glycerin by the action of the third of the pancreatic 

 ferments. The acids set free unite with the alkaline sub- 

 stances present to form soaps. 



The fourth ferment possesses the power of curdling 

 milk, as does rennin, though its action is not identical 

 with that of rennin. It is able to act upon any particles 

 of milk which have by any possibility escaped the influ- 

 ence of the gastric juice. 



331. The Secretory Nerves of the Pancreas have been found 

 to be fibers of the vagus, or tenth cranial nerve, which, as 

 already mentioned, are stimulated by efferent impulses ex- 

 cited in the brain by afferent impulses from the stomach. 



332. Other Functions of the Pancreas. In addition to 

 its office in connection with digestion, experiments have 

 proved that this gland has some further influence upon 

 the general condition of the body ; but what that influ- 

 ence is, is as yet unknown. 



333. The Liver, which weighs from fifty to sixty-four 

 ounces, is the largest gland in the body. It lies chiefly 



