mar 25, 1857 - The Phonautograph was invented
The phonautograph is the earliest known device for recording sound. Previously, tracings had been obtained of the sound-producing vibratory motions of tuning forks and other objects. Invented by Édouard-Léon Scott de Martinville, on the 25 of March 1857 it was patented, Apparently, it did not occur to anyone before the 1870s that the recordings contained enough information about the sound that they could be used to recreate it.
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