The Phonograph

 

Due to his deafness, Edison had great difficulty in perfecting the phonograph. In an 1876 letter to a friend he said, "...I am so deaf that I am debarred from hearing all the finer articulations and have to depend on the judgment of others." In an attempt to compensate, he had this phonograph attached to a wooden frame so that when he bit into it, he could feel the vibrations and "hear" the music.

 

-info supplied by the Edison Ford Museum