60 MANUAL OF CATTLE-FKKDIN-G. 



protein, unites with a fresh quantity, transfers this, again, to the pro- 

 tein, and so on to an indefinite extent. 



If this be true, the similarity between the action of the gastric juice 

 and that of acids is very close. 



The quantity of pepsin concerned in this process is very 

 small J and it is found that the same pepsin is capable of 

 acting over and over again and converting apparently nn- 

 liniited quantities of albuminoids into peptones, provided 

 that more acid is added from time to time. 



It is stated that the digestion of the albuminoids by the 

 pepbin and muriatic acid of the gastric juice, and their 

 conversion into soluble peptones, is facilitated by the pres- 

 ence of a little fat hi the food, and by salt, which causes an 

 increased secretion of the gastric juice. 



It is hindered by dilution of the gastric juice by large 

 amoxmts of drink, and too high or too low a temperature 

 of the drink may, by destroying the pepsin, suspend the 

 digestion altogether, until new pepsin can be secreted. 



The action of the gastric juice on the food is aided by a 

 peculiar action of the involuntary nmscles which form one 

 of the coats of the stomach. These keep the food con- 

 tinually in motion in the stomach, and hi this way mix it 

 thoroughly with the gastric juice, so that all parts of it 

 may be acted upon. 



By means of the gastric juice, aided by the motion of the 

 stomach just described, portions of the food are dissolved, 

 and the whole converted into a more or less fluid mass 

 called Ghytne. 



A portion of the chyme is resorbed in the stomach, and 

 passes directly or indirectly into the circulation. This is 

 the case with the sugar produced fi^om the carbhydrates of 

 the food by the saliva, w^tli the vegetable acids, and in 

 general with the easily soluble constituents of the chyme, 



