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In the 19th century existed very simple mechanical acoustic devices that could transport voice over distance.
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Charles Bourseul publishes a design of a make-and-break telephone transmitter and receive draft, but he dind't construct the invention.
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Johann Philipp Reis constructed the telephone design of Charles Bourseul and demonstrated that it worked
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Thomas Edison experiments with acoustic telegraphy. In November he built an electro-dynamic receiver.