Dictionary illustration of a phonautograph. The barrel is made of
plaster of paris.
The
phonautograph was the earliest known invention of a sound transcription device. It was invented by Frenchman
Édouard-Léon Scott de Martinville and patented on
March 25,
1857. It could transcribe sound to a visible medium, but had no means to play back the sound after it was recorded. The transcriptions, known as
phonautograms, were first successfully played back in 2008, thanks to computer technology.
The device consisted of a horn or barrel that focused sound waves onto a membrane to which a hog's bristle was attached, causing the bristle to move and enabling it to inscribe the sound onto a visual medium. Initially, the phonautograph made recordings onto a lamp-blackened glass plate. A later version (see image) used a medium of lamp-blackened paper on a drum or
cylinder. Another version would draw a line representing the sound wave on a roll of
paper. The phonautograph was a laboratory curiosity for the study of
acoustics. It was used to determine the frequency of a given
musical pitch and to study sound and speech; it was not understood at that time that the waveform recorded by the phonautograph was in fact a recording of the sound wave that needed only a playback mechanism to reproduce that sound.
In 2008, phonautograph recordings were for the first time played back as sound by American audio historians.
The team accessed Leon Scott's phonautograph papers which were stored in France's patent office and the Académie des Sciences. They then optically scanned the etched paper recordings into a computer program developed a few years earlier for the
Library of Congress. The sound waves on the paper were then translated by the computer into audible sounds. One recording, created on
April 9,
1860, was revealed to be a 10-second recording (low fidelity but just recognizable) of the French folk song "
Au Clair de la Lune". While it was initially believed to be the voice of a woman or adolescent, further research in 2009 suggested the playback speed had been too high, and that it was actually the voice of Scott himself.
A phonautogram containing the opening lines of
Torquato Tasso's pastoral drama
Aminta has also been found. Recorded around 1860, probably after April 9, this phonautogram is the earliest known recording of spoken human speech to be played back, predating
Frank Lambert's 1878
recording of a talking clock by twenty-one years and the
Edison Company's 1888 phonographic recording of a
Handel concert by over thirty years. Earlier recordings made in 1857 contain Scott's voice, too, but are unrecognizable due to the irregularity of speed.
See also
