Digestion. 143 



This fluid did not coagulate on heating, nor did it form 

 an emulsion with fatty matter. 



According to Ellenberger and Hofmeister, the succus 

 entericus contains three ferments. Starch can be converted 

 into sugar, cane-sugar into grape-sugar (being the only body 

 secretion, so far as we are aware, which possesses this 

 power), and proteids are converted into peptones. These 

 results were also previously obtained by Colin. They do 

 not harmonize with the views of human physiologists, who 

 attribute but a slight action to the intestinal fluid, and con- 

 sider its chief function is to change maltose into dextrose. 

 Buno-e considers that in the human subject the chief use of 

 the intestinal fluid is to neutralize the acid of the intestinal 

 contents, which it is capable of doing owing to the con- 

 siderable quantity of carbonate of soda it contains ; its 

 further function is to emulsify fats with the surplus soda. 



This view will not hold good for the horse, as the contents 

 of the stomach are no doubt neutralized by the pancreatic 

 and biliary secretions immediately or shortly after they 

 leave the stomach, so much so that on the duodenal side 

 of the pylorus the reaction of previously acid chyme is 

 neutral, and a few inches further back alkaline ; this alka- 

 line reaction, faint at first, becomes more marked as we 

 reach the ileum. 



Reaction of the Contents. — It is strange that on questions 

 of fact any difference of opinion should exist. Ellenberger 

 describes the small intestines as two-thirds acid, then 

 neutral as far as the ileum, where it becomes alkaline. I 

 have only once found it otherwise than alkaline throughout. 

 He further states that in the fasting horse the contents are 

 alkaline, but that in the digesting animal, whether horse, 

 ox, or sheep, they are acid, the acidity decreasing after 

 passing the common duct, and becoming decidedly alkaline 

 at the lower, or what we would call the posterior, portion of 

 the small intestine. This, as I have said, does not agree 

 with my experience in the horse. It is usual to find the 

 duodenum neutral. As we approach the middle of the 

 small intestines the reaction becomes faintly alkaline, whilst 



