On German inventor Johann Philipp Reis' 181st birth anniversary, we revisit the man's most significant innovation, the Reis Telephone
The Reis telephone, an invention by Johann Philipp Reis, a self-taught German scientist and inventor was constructed in 1861. It is considered by many today as the first make-and-break telephone, which thus predates Alexander Graham Bell's telephone, but the actual credit for the telephone's invention is a subject but great dispute to this day.
Reis was inspired to create the phone after reading a French article in 1854 by Charles Bourseul, which talked about creating microphone-like devices.
The Reis telephone
Johann Philipp Reis demonstrated his work to Inspector of the Royal Prussian Telegraph Corps Wilhelm von Legat in 1862. Legat produced an account of the demonstration and its transalation was acquired by none other than Thomas Edison himself, who acknowledged his debt to Reis in a writeup.
The Reis telephone was marginally successful. While the instrument could transmit continuous musical tones it produced indistinct speech. In 1865, however, British scientist David E. Hughes used Reis' telephone with "good results".
Reis. has also been credited for coining the term telephone to describe his invention. In addition to transmitting musical sounds, Reis also used his invention to transmit his phrase, "Das Pferd frisst keinen Gurkensalat". This German phrase, roughly transalated as, 'The horse does not eat cucumber salad", which is difficult to understand acoustically was used by Reis to prove if speech can be recognized on another side successfully.
Johann Philipp Reis
The Reis telephone's loudspeaker worked by magnetostriction, a property of ferromagnetic materials that causes them to change their shape or dimensions during the process of magnetization. Reis coiled a 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 receiver was very insensitive and produced weak sound as a result but had good fidelity and required very high current. It was a current-sensitive device rather than a voltage-sensitive one. An advanced version of the Reis telephone proved effective later, where the iron bar is clamped to a cigar-box-shaped resonator.
Johann Phillip Reis, like Graham Bell came across the idea of creating an apparatus for transitting sound by means of electricity after studying the organs of ear. He had difficulty interesting people in Germany in his invention despite demonstrating it to Wilhelm von Legat. The Reis telephone however generated more interest in the United States In 1872, when Professor Vanderwyde demonstrated it in New York.
European scientists dedicated a monument to Philip Reis as the inventor of the telephone in 1878. This was four years after his death and two years after Alexander Graham Bell received his first telephone patent. After making technical adjustments, engineers from the British firm Standard Telephones and Cables (STC) found Reis' telephone dating from 1863 could transmit and "reproduce speech of good quality, but of low efficiency". This information is courtesy of documents from 1947 in London's Science Museum.
The Johann-Philipp-Reis Preis an award named in Reis' honour is presented biannually to scientists for "....distinguished scientific achievements in the area of communication technology" by the VDE or German electrical engineering association, Deutsche Telekom and the cities of Friedrichsdorf and Gelnhausen.