[Gk. bios, life ; graphein, to write.] An instrument for the reproduction from photographs of seemingly living forms. The photographs are taken on a film in such rapid succession that every phase of movement of the figures is caught as a separate picture. To produce the effect of life the film with its successive pictures is run rapidly through a lantern arrangement, they being thrown on a screen in such quick succession that they blend to the vision and produce a remarkable vivid representation of actual life movements.