The following month the American inventor began work on a way to transmit an automated human voice over the telephone. Apparently, quite independently of Cros, he developed a system where the oscillation of a diaphragm was recorded on a cylinder of tinfoil by means of an attached stylus. In November 1877 Edison announced and then demonstrated his phonograph. He submitted the patent application on Christmas Eve that year and on 19th February 1878 Edison received U.S. Patent 0,200,521 (his 117th US patent) for his ‘Phonograph or Speaking Machine.’
In March 1857, the French printer and bookseller, Édouard-Léon Scott de Martinville, patented the first device for recording sound, the phonautograph. His invention inscribed an image on a cylinder coated in lampblack, which he then pressed onto paper. Unfortunately he had no means to play back the sounds that he had recorded. Twenty years later, another Frenchman, the scientist Charles Cros, had the idea of recording sounds by using an oscillating diaphragm to engrave a cylinder that could then be used to produce a similar oscillation. He submitted his idea to the Academy of Science in Paris in a letter that he sealed in an envelope in April 1877, but he did not make any prototypes of his Paleophone, as he called it.