n.1.(Elec.) A device utilized in the making of a loud-speaking telephone, depending on the fact that the friction between a metallic point and a moving cylinder of moistened chalk, or a moving slip of paper, on which it rests is diminished by the passage of a current between the point and the moving surface.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
* In 1911, Pennsylvania inventor Everett Bickley invented an electric sign he called a motograph (not to be confused with Thomas Edison's motograph receiver, invented in 1872) that spelled out moving messages with a series of light bulbs.
On Times Tower, the Motograph News Bulletin, better known as "The Zipper," began flashing its 14,800 light bulbs.