The 18 April 1877, Charles Cros wrote a letter to the Académie des sciences with details of ‘a method to record and reproduce phenomena perceived by the ear’. It was the first time the world had heard of a description outlining a mechanical method to reproduce sound. On 30 April 1877, the Académie des sciences accepted a sealed cover under the reference 3109.
Unlike Thomas Alva Edison, Charles Cros was not well-known in industrial and scientific circles. He never had the financial means to make a prototype and market his invention known as the phonograph: voice of the past
He died in total destitution on the 9th August 1888.