Stock Photo - An engraving depicting Johann Philipp Reis's ""musical"" telephone: Transmitter (left) and receiver. Johann Philipp Reis (1834-1874) a German scientist, teacher and inventor. Dated 19th century

Stock Photo: An engraving depicting Johann Philipp Reis's ""musical"" telephone: Transmitter (left) and receiver. Johann Philipp Reis (1834-1874) a German scientist.

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