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12 not stand erect and move about. They protect the softer parts of the body. Thus the skull gives protection to the brain, while the ribs protect the heart and the lungs. Doctors have counted 238 bones in the human body. The outside of the bones is hard, but the inside is soft and hollow. Where there is a joint between two bones, there is a coating of marrow, which may be regarded as a soft bone. The teeth, too, are to be counted among the bones.

When we feel the flesh at some points, we find it to be tough and elastic. This part of the flesh is known as the muscle. It is the muscles that enable us to fold and unfold our arms, to move our jaws, and to close our eyes. It is by means of the muscles, again, that our organs of perception do their work.

It is beyond the province of this book to give a detailed account of the structure of the body; nor has the present writer enough knowledge to give such an account. We will, therefore, content our-selves with just as much information as is essential for our present purpose.

The most important portion of the body is the stomach. If the stomach ceases to work even for a single moment, the whole body would collapse. The work of the stomach is to digest the food, and so to provide nourishment to the body. Its relation