The Phonograph and its Applications - Text 1
The phonograph is especially wonderful in that could be used to both listen to recorded cylinders and to capture, preserve and reproduce voices live. It was also possible to restart the recording as many times as one wished: all one had to do was to shave the recorded surface and put the stylus of the diaphragm back on it.[1]
The idea of recording sound independently of the telephone began to emerge when, in his laboratory notebook, Thomas Edison copied on 18 June 1877 the sketch of a device made up of two rollers on which a strip of wax paper unspooled. A “Bell” microphone was placed above the first roller, and the stylus was attached to the diaphragm of this recorder. The reader was set up in identical fashion above the second roller. On 29 November 1877, Edison drew a second device in his laboratory notebook. This “phonograph” was now made up only of a horizontal metal cylinder, mounted on a threaded spindle. Using a crank, the cylinder was turned in a spiralling movement, and the recording was carried out on a sheet of tinfoil wrapped around the cylinder. That same day, he gave the diagram to his collaborator John Kruesi. The employees in the mechanical workshop built an initial “material” prototype between 4 and 6 December 1877, proceeding to the first tests on the latter date.
