SECTION IV. 
DISEASES OF THE DIGESTIVE SYSTEM. 
CHAPTER I. 
DIGESTION. 
Nicety of expression would likely invite confusion, and indeed it is quite 
sufficient to say that the lean portions of meat are very largely digested in the 
stomach. This process does not, however, go on as rapidly in the dog as in 
man; and while in the latter it would ordinarily be completed in the course of 
three or four hours, in the former the end would scarcely be reached before 
the eleventh or twelfth hour. 
The starchy elements of vegetables do not have, to any degree worth men- 
tioning, the helpful influence of the saliva towards their digestion, nor is the 
stomach much, if any, concerned in the process; and soon after they reach it 
they begin to pass downward into the intestines, where they are converted into 
sugar by its fluids, and at once absorbed. Pure starch itself is rapidly digested. 
Indeed, under experiment it has been found that three-quarters of an hour after 
a moderately full meal of boiled starch and meat, all traces of the starch and 
sugar had disappeared from both the stomach and intestines. The conversion 
of some starchy foods, however, seems to be quite slow. For example, potatoes, 
when well cooked and mashed, disappear in the course of two or three hours, 
but if not broken up they remain five or six hours. The digestion of boiled rice 
commences at once, but its conversion is slow, and traces of it can generally be 
found even at the seventh or eighth hour. Although milk is considered one of 
the most easily digestible of foods, as a matter of fact its digestion is compara- 
tively a slow process. 
The fats or oily matters in foods are not digested in the stomach, but, melted 
by its warmth and the tissues containing them being partially broken up and 
digested by the gastric juice, they pass into the intestines, where the oil globules 
are freed, and then emulsified ; or, in other words, they are minutely subdivided, 
so that they are capable of being absorbed. This, practically, is the extent of 
their digestion. 
As stated in substance, when the food is meat, stomach digestion, if normal, 
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