4. The drinking of strong liquors often causes incurable disease of the kidneys.
CHAPTER XVIII.
OUR BONES AND THEIR USES.
1. The Bones.—In an earlier chapter we learned something about the bones. This we must try to recall. You will remember that we called the bones the framework of the body, just as the timbers which are first put up in building a house are called its frame.
2. The Skeleton.—All the bones together make up the skeleton. (See page 95.) There are about two hundred bones in all. They are of many different shapes. They vary in size from the little bones of the ear, which are the smallest, to the upper bone of the leg, which is the largest in the body.
3. The skeleton is divided into four parts: the skull, the trunk, the arms, and the legs. We must learn something more about the bones of each part.
4. The Skull.—The skull is somewhat like a shell. It is made of a number of bones joined together in such a way as to leave a hollow place inside to hold the brain. The front part of the skull forms the framework of the face and the jaws. In each ear there are three curious little bones, which aid us in hearing.
5. The Trunk.—The bones of the trunk are, the ribs, the breast-bone, the pelvis, and the back-bone. The bones of the trunk form a framework to support and protect the various organs within its cavities.