Reis telephone

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This article is about the invention by Phillipp Reis. For other uses, see Telephone (disambiguation).
"100 Years - Philipp Reis - 1861": a German postal stamp commemorating the centenary of Reis' achievement, issued October 1961

The Reis telephone, was an invention by Philipp Reis inspired by a French article in 1854 (by Charles Bourseul) on how to create microphone-like devices. His first successful work was achieved in October 1861.

Later developments[edit]

In 1862, Reis demonstrated his telephone to Wilhelm von Legat, Inspector of the Royal Prussian Telegraph Corps who produced an account of it (Legat, 1862), a translation of which was obtained by Thomas Edison in 1875 and was used in Edison's successful development of the carbon microphone. (The Legat account included drawings that are different from the one below suggesting that it is of a later version). Edison acknowledged his debt to Reis thus:

The first inventor of a telephone was Phillip Reis of Germany only musical not articulating. The first person to publicly exhibit a telephone for transmission of articulate speech was A. G. Bell. The first practical commercial telephone for transmission of articulate speech was invented by myself. Telephones used throughout the world are mine and Bell's. Mine is used for transmitting. Bell's is used for receiving. (Edison 2006, [LB020312 TAEM 83:170])

However Reis' telephone was not limited to musical sounds. Reis also used his telephone (the word also invented by Reis) to transmit his phrase"Das Pferd frisst keinen Gurkensalat" (The horse does not eat cucumber salad). This phrase in German is hard to understand acoustically so Reis used it to prove if speech can be recognized on another side successfully.[1]

Loudspeaker[edit]

Reis's speaker worked by magnetostriction. In his first receiver he wound a coil of wire around an iron knitting needle and rested the needle against the "F" hole of a violin. As current passed through the needle, the iron shrank and a click was formed. The image shown below is a more advanced version where the iron bar is clamped to a cigar-box-shaped resonator. This receiver is very insensitive. It produces weak sound but has good fidelity. It requires very high current and is a current-sensitive device rather than a voltage-sensitive device.

Reis was marginally successful. This instrument could transmit continuous musical tones but produced indistinct speech. In 1865, however, British scientist David E. Hughes used Reis' telephone with "good results".[2]

Johann Philipp Reis telephone.jpg

See also[edit]

References[edit]

External links[edit]

References[edit]

  1. ^ "The Telephone" by Discovery Channel
  2. ^ Nature 106, p. 650