Page:Popular Science Monthly Volume 11.djvu/724

704  of the future" will be? We ourselves complacently regard our age and its works, while anticipating the constant progress of the human race and its increasing ability to "reveal itself in tones."



O those unacquainted with the mysterious parlance of the anatomist, the use of strictly scientific terms might prove discouraging and fail to interest. I shall therefore discard the scientific in favor of the every-day phrases, in explanation of the following figure (1), which, it will be observed, represents a human head split from above downward through the central line.

Through the only two channels in which the air travels in going to the lungs, namely, through the nose and mouth, are drawn two arrows,



a and b. These two passages unite in a common cavity at f, and from that point there is but one tube leading to the lungs.

At c is a bone called the hard palate, which forms the roof of the mouth and the floor of the nose, separating these two air-channels from each other. At the inner or posterior end of the bone, c, is seen a little body, d, called the soft palate, made of muscle and covered with a delicate skin. This soft palate is attached at one end to c, the hard palate; the other end hangs loose, and moves or flaps in the act of breathing, something like a window-curtain when acted upon by a current of air. This is its condition while we are asleep or awake, though during sleep it lacks in tonicity, being much more relaxed, or flabby, than when we are awake. At e is represented the tongue.