Jasper County Democrat, Volume 20, Number 7, Rensselaer, Jasper County, 21 April 1917 — Vibrations Make Sound. [ARTICLE]

Vibrations Make Sound.

Anything stretched is likely to be thrown into vibration, or made to tremble, by the force of the air blowing against it. If At vibrates sO fast as to produce the air waves that our ear can hear, thep that is what we call sound. This is what happens to the telegraph wires when they hum; and if we put our hand on the telegraph pole we shall feel that the wires vibrate strongly enofigh to set the whole pole to trembling, too. When the air is quite still you will not hear the telegraph lines humming.