120 A Manual of Veterinary Physiology. 



the period of digestion ; we have previously drawn attention 

 to the fact that an hour or two after hay has been taken, 

 the material is found in a finely chopped condition, firm, 

 one may almost say dry in places, though towards the 

 pylorus it is liquid. This ha}' contains between four and 

 five parts of saliva ; is yellow in colour where the gastric 

 juice has attacked it, but rather of a greenish tint else- 

 where. It has a peculiar odour. Some hours after a feed 

 the stomach is found to contain a variable quantity of 

 watery fluid discoloured by the hay which is left behind, 

 part of which may be found floating on the fluid. At 

 other times, when the stomach is empty, the fluid is viscid, 

 contains numerous air bubbles, and is of an amber or 

 yellow tint. This particular fluid is no doubt saliva and 

 mucin, with possibly a little bile. 



When oats alone have been given the contents of the 

 stomach are found liquid, the fluid being creamy in con- 

 sistency and colour ; the oats are swollen, soft, and their 

 interior exposed. Towards the end of digestion the creamy 

 fluid is repfaced by the frothy yellow one. With both hay 

 and oats, and also other foods, there is a peculiar sour- 

 milk-like smell from the contents of the stomach, more 

 marked with bran and oats than with hay, which, as 

 previously mentioned, smells like sour tobacco. 



The reaction of the contents of the stomach is strongly acid ; 

 this acid reaction may be obtained on the cuticular as well 

 as the villous portion of the viscus, and is very persistent : 

 the cuticular membrane even after prolonged washing- 

 gives an acid reaction. The acidity is derived entirely from 

 the juice secreted by the villous membrane of the fundus. 



My observations on this subject do not agree with those 

 of Ellenberger, who says that during the first hour of 

 digestion the stomach maybe alkaline; acidity then com- 

 mences in the fundus and extends to the eanlia, though 

 for some time the proportion of fundus acidity is three or 

 four times greater than that of the cardia; in the course 

 "f live or six hours the proportion of acid throughout the 

 stomach is equal. 



