Address by Charles Cros, poet and inventor (1842-1888) at the Academy of Sciences of Paris...

Address by Charles Cros, poet and inventor (1842-1888) at the Academy of Sciences of Paris on April 18, 1877. Description of a method of recording and reproducing sounds for the Invention the Phonograph Principle. Transcript of photograph text, first and last page: “” In general, my method is to obtain the trace of back and forth of a vibrating membrane and to use this trace to reproduce the same back and forth, with its intrinsic relationships of hardness and intensity, on the same membrane or on another suitable to render the sounds and sounds that result from this series of movements.