Text: " The laws of transverse vibrations in strings are simple and easily demonstrable. It can be shown that the velocity with which they travel along a flexible chord is equal to the square root of the tension applied to it divided by the mass of it's unit length. The disturbence of any point in a string causes two pulses to start from this point and run along it in opposite directions. Each of these, on arriving at the end, is reflected from the support to which it is attached,and undergoes reversal as to side. It runs back thus reversed to the other end, and is there again reflected and reversed. When it arrives at the origin of the disturbence it has travelled over twice the length of the string, the other pulse arriving there at the same instant. The period of a complete vibration is therefore that required for a wave to travel over twice it's length" Scientific Basis of Music - W.H.Stone

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