Inventions


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Sounds were recorded for the first time in 1877 on an experimental machine that Thomas Edison hoped would translate telephone calls into telegraph messages. It recorded the calls as indentations in a strip of paper passing under a stylus. Edison noticed that when he passed the indented paper through the machine again, he heard a faint echo of the original sound. This mechanical-acoustic method of recording continued until electrical systems appeared in the 1920s according to Invention (Dorling Kindersley) one of thousands of titles available in the Gale Virtual Reference Library.

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