Heaviside, Oliver

Heaviside, Oliver (hev'ēsīd") [key], 1850–1925, English physicist. He did valuable work in telephony and in the theory of electrical conduction in cables and other areas of electric theory. He suggested (1902) the existence of a layer in the upper atmosphere responsible for altering the path of certain radio waves and thus making possible long-distance transmission of signals. The same conclusion was reached independently by Arthur E. Kennelly; its existence was proven, and it is known both as the Kennelly-Heaviside layer and as the Heaviside layer. See ionosphere.