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The phonograph was developed as a result of
Thomas Edison's work on two other inventions, the telegraph and the telephone. In 1877, Edison was working on a machine that
would transcribe telegraphic messages through indentations on paper tape, which could later be sent over the telegraph repeatedly.
This development led Edison to speculate that a telephone message could also be recorded in a similar fashion. He experimented
with a diaphragm which had an embossing point and was held against rapidly-moving paraffin paper. The speaking vibrations
made indentations in the paper. Edison later changed the paper to a metal cylinder with tin foil wrapped around it. The machine
had two diaphragm-and-needle units, one for recording, and one for playback. When one would speak into a mouthpiece, the sound
vibrations would be indented onto the cylinder by the recording needle in a vertical (or hill and dale) groove pattern. Edison
gave a sketch of the machine to his mechanic, John Kreusi, to build, which Kreusi supposedly did within 30 hours. Edison immediately
tested the machine by speaking the nursery rhyme into the mouthpiece, "Mary had a little lamb." To his amazement, the machine
played his words back to him.
Edison's original sketch of his
first phonograph
The Improved 1879 Version
Edison tin foil phonograph pictured above was obtained from Edison in 1879 by Gardiner G.
Hubbard and given to Alexander Graham Bell for the purpose of improving the phonograph. The machine was used to make experimental
recordings in wax but by the old indenting method that Edison had originally used in 1877. After two years of experiments,
Bell and Charles Tainter sealed this machine, called a "graphophone" by Bell, inside a tin box for deposit at the Smithsonian
Oct. 20, 1881. The box was opened Oct. 27, 1937.
Thomas A. Edison
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