Source : Webster's Revised Unabridged Dictionary (1913)

Motograph \Mo"to*graph\, n. [L. movere, motum, to move +
   -graph.] (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. --
   {Mo`to*graph"ic}, a.