98 THE HUMAN BODY. 



CHAPTER VII. 



DIGESTION AND ABSORPTION. THE 

 LYMPHATIC SYSTEM. 



SECTION I. 1. Pood repairs the waste of the body, and 

 keeps up life. If asked how it is made to do this, you 

 could answer, " It is eaten." By that, you mean that it is 

 taken into the mouth, and chewed, and swallowed. But 

 if asked again, What becomes of it after it is swallowed, 

 and how does it get into our bones and flesh and brains, 

 and keep every particle living, and perhaps growing, you 

 could not answer without study. For, in health, we know 

 nothing about our food, by our feelings, after it is swal- 

 lowed. 



2, If, however, we examine into the matter, we find that 

 the food, after being swallowed, passes on down a tube 

 which extends through the whole length of the trunk, be- 

 ginning at the lips. This tube is the alimentary canal. 



3, The alimentary canal is about twenty-seven feet long, 

 in a man. In order to get it into the trunk of the body, 

 which is only about two feet long, a portion of it is coiled 

 up in a mass. This portion we call the bowels. 



4, Most of the canal is about an inch and a half wide. 



SUGGESTIONS TO TEACHERS. 1. An emulsion can be made with oil and 

 the white of an egg, or with mucilage obtained from the druggist's. This 

 can be compared with a mixture of water and oil. 



2. A tube made of chamois leather, or a cone of filter-paper, will illus- 

 trate the soaking through membranes. 



