28 THE WONDERFUL HOUSE THAT JACK HAS 



it secretes about ten ounces, or a little more than 

 a half pint daily. Pancreatic juice digests starch, 

 fat, and proteid. We found that the lining of the 

 stomach contained many small tubes which se- 

 creted gastric juice. In the lining of the small intes- 

 tine are also small tubes that secrete the last of 

 the digestive fluids, the intestinal juice. The fluid 

 that pours from these tubes is supposed to aid in 

 the digestion of proteids, fats, starches, and sugar. 

 These intestinal glands form, as it were, clearing up 

 workshops that help digest any food material which 

 arrives in an unprepared state. The intestinal tubes 

 are thought to secrete about one-half pint daily. 



The quantity of the digestive fluids and the 

 special work of each have been discovered by ex- 

 periments. Many of these have been tried on dogs 

 and other animals. Much valuable information has 

 also been gained by doctors from patients with wounds 

 in some part of the stomach or intestines, through 

 which the digestive processes were watched. 



After chyme has been acted upon by the di- 

 gestive juices of the intestines, it becomes changed to 

 a milky white fluid called chyle. How does chyle 

 get into the blood? All along the inner lining of the 

 small intestine, for a distance of about twenty feet, 

 there are small, hair-like projections called mill. These 

 are few in number near the stomach, but gradually 

 become so numerous that they give the inside of the 

 intestine a velvety appearance. These little villi 



