‎"CROS, CHARLES. - INVENTING THE PHONOGRAPH.‎
‎""Procédé d'enregistrement et de reproduction des phénomènes perçus par l'ouïe"". (Seance du Lundi 3 decembre 1877).‎

‎(Paris, Mallet-Bachelier), 1877 4to. In: ""Comptes Rendus Hebdomadaires des Séances de L'Academie des Sciences"", Tome 85, No 23. Pp. (1029-) 1084. (Entire issue offered). Cros' letter: pp. 1082-1083.‎

Reference : 49293

‎First printing of this paper which describes the invention of the Phono-autograph (Phonograph) a few month before Edison introduced his invention. It was on this letter to the Academy that the French made claim to the invention.""He (Charles Cros) is perhaps most famous as the man who almost, but not quite, invented the phonograph. No one before M. Charles Cros had thought of reproducing sound by making an apparatus capable of registering and reproducing sounds which had been engraved with a diaphragm. The inventor gave the name of Paleophone (voix du passé) to his invention. On April 30, 1877 he submitted a sealed envelope containing a letter to the Academy of Sciences in Paris explaining his proposed method. The letter stated in French, ""Alors qu'il séjourne à Sablé au début de 1877, Charles Cros rédige une courte note, « Procédé d'enregistrement et de reproduction des phénomènes perçus par l'ouïe », dans laquelle il expose le principe de ce qu'il nomme « Paléophone » (« voix du passé ») : « Un index léger est solidaire du centre de figure d'une membrane vibrante "" il se termine par une pointe [...] qui repose sur une surface noircie à la flamme."" The English translation is one close to this: ""A lightweight index is fixed to the center of figure of a vibrating membrane, it ends with a tip [...] based on a blackened surface flame. This surface is integral with a disc driven by a double movement of rotation and linear progression. The system is reversible: when the tip makes ironing in the furrow membrane restores the original acoustic signal."" The letter was read in public on 3 December following. In his letter, after having shown that his method consisted of detecting an oscillation of a membrane and using the tracing to reproduce the oscillation with respect to its duration and intensity. Cros added that a cylindrical form for the receiving apparatus seemed to him to be the most practical, as it allowed for the graphic inscription of the vibrations by means of a very fine-threaded screw.""(Wikipedia)‎