 Until 2008 it was considered to be the oldest surviving sound recording but a phonautogram of Au Clair de la Lune by Édouard-Léon Scott de Martinville from 1860 has been found to pre-date it.However, Lambert's recording is still the oldest which can be played with its own original device, unlike the phonautogram which was played by optically scanning it and using a computer to process the scan into a digital audio file.Lambert completed his main invention, a typewriter on which the keyboard consists of one single piece.