The Reis telephon was an early sound transmitting device, invented by

Philipp Reis Johann Philipp Reis (; 7 January 1834 – 14 January 1874) was a self-taught German scientist and inventor. In 1861, he constructed the first ''make-and-break'' telephone, today called the Reis telephone. It was the first device to transmi ...

in 1857. Reis's first successful work is dated to October 1861. When properly set up, it would allow verbal communication via electronic signals. Many sources credit Reis as the inventor of the first telephone. Others point to the prior work of Antonio Meucci, or to later work of

Elisha Gray Elisha Gray (August 2, 1835 – January 21, 1901) was an American electrical engineering, electrical engineer who co-founded the Western Electric, Western Electric Manufacturing Company. Gray is best known for his Invention of the telephone, dev ...

Alexander Graham Bell Alexander Graham Bell (; born Alexander Bell; March 3, 1847 – August 2, 1922) was a Scottish-born Canadian Americans, Canadian-American inventor, scientist, and engineer who is credited with patenting the first practical telephone. He als ...

. However it is generally agreed that Reis coined the word ''telephon'' -- which has been Anglicised to

telephone A telephone, colloquially referred to as a phone, is a telecommunications device that enables two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most ...

History

In 1861, Philipp Reis succeeded in creating a device that captured sound, converted it to electrical impulses that were transmitted via electrical wires to another device, which transformed these pulses into recognizable sounds similar to the original acoustical source. Reis coined the term ''telephon'' to describe his device. In 1862, Wilhelm von Legat, Inspector of the Royal Prussian Telegraph Corps, published an article on Reis' invention. von Legat provided a theoretical explanation for

why, in the practical experiments... melodies... are transferred with astonishing correctness, whereas single words in reading, speaking, and so forth, could be noticed less distinctly, not withstanding here, also, the flexions of the voice are allowed to assist the interrogatory, exclaiming, astonishing and appealing cadence. Undoubtedly, the matter discussed here, before attaining a practical form, will need considerable perfection... Still, I am persuaded, after repeated practical experiments, that the following up of this matter will prove to be of the highest theoretical interest, and its practical realization in this intelligent age will not be long delayed.

In 1865,

David Edward Hughes David Edward Hughes (16 May 1830 – 22 January 1900), was a British-American inventor, practical experimenter, and professor of music known for his work on the printing telegraph and the microphone. He is generally considered to have bee ...

tested Reis' invention at St Petersburg, finding that it was "often" able to successfully transmit words "due to an accidental adjustment of tscontacts to a true microphonic condition". A translation of Legat's article on Reis' invention was obtained by

Thomas Edison Thomas Alva Edison (February11, 1847October18, 1931) was an American inventor and businessman. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These inventions, ...

prior to his filing his patent application on a telephone in 1877. In correspondence of 1885, Edison credits Reis as having invented "the first telephone", with the limitation that it was "only musical not articulating". In 1878, Edison's recently-patented design for a telephone was explained by inventor Samuel M Plush as having been based on Reis' 1861 invention. Plush described Reis' invention as being "the first telephone", explaining that "This apparatus was capable of reproducing but one of the characteristics of sound, viz., pitch. Further experiment was necessary to reproduce its quality and dynamic force."

Microphone

As Reis was considering his invention as a means of broadcasting music, he termed his

microphone A microphone, colloquially called a mic (), or mike, is a transducer that converts sound into an electrical signal. Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and publi ...

the 'singing station'. The Reis microphone was based on a horizontal

parchment Parchment is a writing material made from specially prepared Tanning (leather), untanned skins of animals—primarily sheep, calves and goats. It has been used as a writing medium in West Asia and Europe for more than two millennia. By AD 400 ...

diaphragm as a sound transducer. The diaphragm was mounted on the top of a closed wooden sound box, with a speaking horn on the front. Sound received by the horn caused the diaphragm to vibrate. Above this were two brass strips, later with two platinum contacts, originally with a single platinum contact, and the lower contact formed of a drop of mercury in a recess at the end of the screw. One strip was glued to the center of the diaphragm; another strip, usually two strips in a V, was mounted above this. The strip's weight gave a light pressure between the contacts. Sound vibrations caused the diaphragm and lower contact to vibrate in sympathy. This changed the resistance between the two contacts, giving an electrical signal to the telephone line.

Patent dispute in the US

There was some question as to the operation of the Reis microphone. It is regarded today as having varied the ''resistance'' of the contacts. However, Reis's description claimed that the contacts opened and closed. At the time, it was held that a circuit with such a 'make and break' circuit was incapable of transmitting intelligible speech. Reis's device had been used to transmit speech from 1861, and widely publicly demonstrated from 1863, yet when Bell's patent claim was set against Reis's primacy of inventing the telephone this 'inability' for it to work because of its use of a "false theory" was enough to (legally) portray Reis's invention as invalid, thus allowing Bell to claim novelty. Historian Lewis Coe identified another reason why Reis was unable to claim priority in US Patent disputes:

Possibly the main reason that the Reis priority never stood up in court was that no one seemed to be able to demonstrate a Reis instrument in the transmission of articulate speech. Once, when attorneys were attempting to demonstrate the Reis instrument in court they could not get the right adjustment on the apparatus, succeeding only in producing squeaks and squawks, but no speech. Finally, one of them in disgust exclaimed, "it can speak, but it won't."

Loudspeaker

Reis's speaker worked by

magnetostriction Magnetostriction is a property of magnetic materials that causes them to change their shape or dimensions during the process of magnetization. The variation of materials' magnetization due to the applied magnetic field changes the magnetostrictive ...

. 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 produced. The image, below, shows an advanced version where the iron bar is clamped to a cigar-box-shaped

resonator A resonator is a device or system that exhibits resonance or resonant behavior. That is, it naturally oscillates with greater amplitude at some frequencies, called resonant frequencies, than at other frequencies. The oscillations in a reso ...

. This receiver is not very sensitive. It produces weak sound but has good

fidelity Fidelity is the quality of faithfulness or loyalty. Its original meaning regarded duty in a broader sense than the related concept of '' fealty''. Both derive from the Latin word , meaning "faithful or loyal". In the City of London financial m ...

. It requires very high current and is a current-sensitive device rather than a

voltage Voltage, also known as (electrical) potential difference, electric pressure, or electric tension, is the difference in electric potential between two points. In a Electrostatics, static electric field, it corresponds to the Work (electrical), ...

-sensitive device.

References

* Legat, V. 1862
"Reproducing Sounds on Extra Galvanic Way"
accessed 26 March 2006. * Friedrich Georg Wieck, Otto Wilhelm Ålund "''Uppfinningarnas bok''" vol. II, 1874. * Thompson, Sylvanus P. "''Philipp Reis, Inventor of the Telephone''" London: E. & F.N. Spon, 1883. * Coe, Lewis "''The Telephone and Its Several Inventors: A History''" Chapter 2, McFarland & Co, 1995.

External links