The skull is a hollow box intended to hold and protectthe brain. It is built of eight separate bones, most of them broad flat plates. They are joined together firmly at their edges, because, as they simply form a box, there is no need for these bones to move. The face comprises all the rest of the head that is not included in the skull. It is formed of no less than fourteen separate bones. Theonly thing calling for special notice in the arrangement of these bones is the provision, which is made by them for the protection of the eyes, by lodging those organs in great hollows formed in the bones themselves. These hollows are called the orbits or sockets of the eyes. Notice how providentially they are surrounded by the broad frontal-bone of the forehead above, the
nose-bone between them, and the cheekbones below. These effectually protect the delicate organs from injury. Only one of all these fourteenbones of the face is capable of movement. Which is it?
The lower jawbone moves so as to open and close the mouth. It is attached on either side by a sort of hinge to the other bones of the skull.
