How long Food stays in the Stomach.—A ring of muscle around the end of the stomach keeps the food from escaping until it has become a thin grayish liquid. The stomach can finish its work on some kinds of food in one or two hours. With other foods it must work four or five hours.
The stomach can finish its work on soft boiled eggs, milk, roasted potatoes, and broiled lamb within two hours. With pork, veal, cabbage, and fried potatoes it must work four or five hours. When a person is sick the stomach is weak, and he should have only the food which causes the stomach the least work.
The Work of the Intestines.—The last part of the work in getting the food ready for the blood is done in the long folded tube known as the intestine ([Fig. 27]). Here juices coming from the pancreas and liver mix with the food and change into a liquid those parts not acted on in the stomach.
The intestine does quite as much work as the stomach. Sometimes when the stomach is sick, too much work is put off on the intestines and then they become sick and give much pain.
The pint of watery fluid from the pancreas and the quart of greenish yellow fluid called bile given out by the liver are carried through two tubes into the intestine ([Fig. 27]). To mix these juices with the food the intestine is being swung gently back and forth and the walls squeezed together by muscles forming its outer coat. As soon as the intestine has finished its work the food begins to enter the blood.
Fig. 27 —The organs which get the food ready to enter the blood.
