sound wave

Similarly a sound wave in air is reflected upon striking the surface of a body.

During a complete vibration of the fork, therefore, the sound wave moves four times the length of the air column.

Let the curve A represent the sound wave sent out by one tuning fork and B, that sent out by the other.

The result was that I saw a wave of compression, of the same sort as a sound-wave in air, move through the throng.

Now the actions and reactions between the air-particles in a sound wave are purely mechanical.