1868 __ Transmission of vocal melodies
‣ Comment : The Reis telephone was brought to America by Dr. P. H. Van der Weyde, a well-known physicist in his day, and was exhibited by him before a technical audience at Cooper Union, New York, in 1868, and described shortly after in the technical press. The apparatus attracted attention, and a set was secured by Prof. Joseph Henry for the Smithsonian Institution. (Compiled from various sources) — The invention of the [Telephone of Mr. Reiss] dates from 1860, and Professor Heisler speaks of it in his teatrise of technical physics, published at Vienna in 1866; he even asserts, in the article which he devotes to the subject, that although the instrument was still in its infancy, it was capable of transmitting vocal melodies, and not merely musical sounds. The system was afterwards perfected by M. Van der Weyde, who, after reading the account published by M. Heisler, sought to make the box of the sender more sonorous, and to stregthen the sounds produced by the receiver. (Theodore du Moncel) — Van der Weyde had described for a receiver an electromagnet mounted on a sounding box. Joseph Henry had reported years earlier that an electromagnet expands slightly when magnetized and contracts slightly when dematignetized. So an intermittent current makes it vibrate and produce a sound of the same frequency. Charles G. Page of Salem had discovered that effect and made “galvanic music” with it in 1837. The transmitter described by Van der Weyde had been invented in 1860 by a German named Philipp Reiss. Unlike the rheotomes of Bell and Gray, it presaged the telephone transmitter, for it picked up and transmitted the pitches of outside sounds, using a membrane diaphragm with a platinum contact point in its center that made and broke the battery-powered current. But of course the intermittent current did not vary in strength to correspond with the volume of the circuit-breaking sound. And therefore, since Reis’s instrument could not reproduce amplitudes or degrees of loudness, it could never transmit the subtle compound of many frequencies and amplitudes that constitutes speech. It could convey the rhythms and pitches of speech and thereby the illusion of intelligibility. — but only the illusion. Reiss did not choose to patent what he regarded as a purely scientific experiment. And indeed it had no conceivable commercial use then nor would it ever. Reiss called his device a “telephone”. He was not the first to use the word. As far back as 1796 another German had coined it, perhaps for the first time, from Greek roots meaning “far-speaking”. Until Reiss, the word referred to mechanical conductors of sound, such as speaking tubes. After Reiss published an account of his ‘telephone” in 1861, it became well known among physicists and in lecture demonstrations. Eventually it appeared in several forms, including the one described by Van der Weyde. In all of them, a sound-vibrated membrane repeatedly interrupted a battery-powered current, and the intermittent current produced a sound in an electromagnet core, amplified by a sounding-box base. (Robert Bruce)
‣ French comment : Vander Weyde présente à l'Institut Américain une version améliorée du téléphone de Reiss. (Compiled from various sources)
‣ Original excerpt : « In 1868 I caused two telephones to be made, similar to those I have described, and I exhibited them at a meeting of the Polytechnic Club of the American Institute. The transmitted sounds were produced at the farthest extremity of the Cooper Institute, quite outside the hall in which the audience sat : the receiver was placed on a table in the hall itself. The vocal airs were faithfully reproduced, but the sound was rather weak and nasal. I then tried to improve the instrument, and I first obtained stronger vibrations in the box [K] by causing reverberation from the sides of the box, by means of hollow partitions. I next intensified the sounds produced by the receiver, by introducing several iron wires into the coil instead of one. These improvements were submitted to the meeting of the American Association for the Advancement of Science, which was held in 1869, and it was considered that the invention contained the germ of a new method of telegraphic transmission which might lead to important results. » (In American Scientific Journal)
‣ Source : Du Moncel, Theodore (1869), “Notice sur le cable transatlantique”, Gauthier-Villars, Paris, pp. 20.
‣ Source : Bruce, Robert V. (1990), “Bell: Alexander Graham Bell and the conquest of solitude”, Cornell University Press, pp. 117-118.
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