Thomas Alva Edison rose from celebrity to eminence, accepting an invitation to present his talking phonograph to the National Academy of Sciences at the Smithsonian Institution in Washington. George Barker of the University of Pennsylvania organized a public comparison of telephones made by Bell, Phelps, Gray, and Edison. The first three, all magnetic, suffered from weak signals and co-interference on the Philadelphia line, while Edison’s, thanks to its carbon transmitter, sounded loud and clear.
