“The voice of the artist, singer, speaker or the music for dance were recorded in the studio. The actors then rehearsed their roles until they had obtained a perfect synchronization with the phonographic recording. Then the cinematographic record was taken. The two instruments, photo and phono, were united by an electric contrivance which assured their synchronization.”

Alice Guy, The Memoirs of Alice Guy Blaché, a cura di Anthony Slide, Scarecrow Press, Metuchen, 1981, p. 44