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1866 __ First wireless telegrapher
Mahlon Loomis (1826-1886)
Comment : In 1866, the American Mahlon Loomis experimented with a system for transmitting electrical signals in the atmosphere between two kites covered with copper wire screens, linked to a galvanometer and 18 miles apart. (Compiled from various sources)Loomis, a Washington, DC dentist, claimed to have transmitted signals in October 1866 between two Blue Ridge Mountain-tops 14 miles apart in Virginia, using kites as antennas, but with no independent witnesses present (Shaw, E. C. (1979). DX-ing according to NASWA. Liberty, Ind: North American Short Wave Association). Loomis received U.S. Patent 129,971 for a wireless telegraph in 1872.[5] This one-page patent makes a vague claim about using atmospheric electricity to eliminate the overhead wire used by the existing telegraph systems, but it contains no schematic diagram of how to build it, and no theory of how it might function. Loomis envisioned towers "on the tops of high mountains, and thus penetrate or establish electrical connection with the atmospheric stratum ... to form the electrical circuit." Loomis's patent is substantially similar to U.S. Patent 126,356 received three months earlier by William Henry Ward who applied for the patent on June 29, 1871 when Loomis was actively promoting his idea of using atmospheric electricity for telegraph communication. Ward's patent also contains no schematic diagram. Instead, Ward illustrates and describes towers that rotate into the wind "to drive an aerial current of electricity into the insulated middle portion of the tower, which current passes upwardly through the upper portion of the tower and out through the ventilator or the top... whereby the tower is receiving continually fresh and new supplies of electricity". The two patents in some places use almost identical language: "I also dispense with all artificial batteries, but use the free electricity of the atmosphere, co-operating with that of the earth... for telegraphing and for other purposes, such as light, heat, and motive power." (Loomis)"I entirely dispense with artificial batteries, forming my circuit merely by connecting the aerial current with the earth current... for the use of land lines of telegraphs or for other purposes, such as light, heat, &c." (Ward) In January 1873, the United States Congress declined to charter the Loomis Aerial Telegraph Co. One congressman, pleading Loomis' case in the House, said, "He entertains a dream, and it may be only a dream, a wild dream that when his proposition comes to be fully applied, it may light and warm your houses...." Loomis, himself, addressed Congress at one point, stating that his proposal functioned by "Causing electrical vibrations or waves to pass around the world, as upon the surface of some quiet lake one wave circlet follows another from the point of the disturbance to the remotest shores, so that from any other mountain top upon the globe another conductor, which shall pierce this plane and receive the impressed vibration, may be connected to an indicator which will mark the length and duration of the vibration; and indicate by any agreed system of notation, convertible into human language, the message of the operator at the point of the first disturbance." Loomis noted that transmission was possible only when the kites were flown to the same altitude above ground, which seemed to confirm his hypothesis that he was completing a DC circuit through layers of the atmosphere that he hypothesized carried such currents. We know now that there is no basis for such a system. One version of the Loomis apparatus used a keyed connection to ground at the transmitting station, and a spark gap to ground at the receiver. Radio frequency transients would have been generated by keying the sky-ground DC potential at the transmitter, and if the kite wires were of the same length (which would have the kites at the same altitude above terrain), the receiving apparatus would have been resonant and able to receive such a signal. This may account for his result.not by tapping into the same layer of atmosphere, but because the wires were the same length. (Compiled from various sources)
French comment : Le fait de pouvoir le considérer comme un des inventeurs de la radio repose sur les expériences qu'il a semble-t-il menées en octobre 1866 dans les Blue Ridge Montains (Montagnes Bleues), en Virginie, 8 ans avant la naissance de Marconi et un an seulement après la fin de la Guerre de Sécession. Parmi les témoins des expériences de Loomis, se trouvaient des personnes sérieuses, tel le Sénateur Samuel Pomeroy du Kansas et un membre du Congrès américain John A. Bingham de l'Ohio, qui appuyèrent ses demandes de subvention au gouvernement fédéral pour commercialiser son invention. Le dispositif utilisé par Malhon Loomis était très simple et pourrait être refait sans peine aujourd'hui. Il avait construit 2 stations distantes de 18-20 miles (28-30 Km) en vue directe entre deux collines. Dans chaque station il y avait un cerf-volant auquel était accroché une toile métallique de cuivre d'environ 40 cm de coté (15-inch), un fil de cuivre d'environ 200 m (600') pour relier le cerf-volant et un galvanomètre. Les gens qui conduisaient l'expérience avaient calé leurs montres sur la même heure. A intervalles déterminés, un opérateur mettait le fil à la masse au travers du galvanomètre sur le cerf-volant "émetteur". Loomis constata que le galvanomètre du cerf-volant "récepteur" déviait chaque fois que le cerf-volant "émetteur" était mis à la masse. Il répéta plusieurs fois l'expérience et vérifia chaque fois le même résultat. Les possibilités d'une exploitation commerciale du procédé apparurent rapidement intéressantes. Cependant Loomis compris assez vite qu'il était nécessaire de développer un "détecteur" plus sensible que le galvanomètre s'il voulait faire des transmissions sur plus longue distance sans augmenter de façon prohibitive la surface de sa grille et la taille du cerf-volant. Il fit ériger une vraie antenne en acier et continua ses expériences, mais le coût financier de ses travaux fut pour lui un perpétuel problème. Ses expériences firent grand bruit dans les années 1870. Une grande controverse éclata même au Congrès en 1869 quand l'éminent Sénateur du Massachusetts, Charles Summer, présenta une note de $50,000 pour subventionner les travaux de Loomis. Pendant 2 ans, le paiement de cette note fut même bloqué en commission, sans doute à cause du lobby du télégraphe qui voyait d'un mauvais oeil le développement de ce nouveau mode de transmission de signaux à distance. En janvier 1873, Bingham membre du congrès fit une note à la Chambre des Représentants en vue de la création de la Société LOOMIS AERIAL TELEGRAPH COMPANY (sans apport de subventions de l'Etat disait la note). La note d'accompagnement était signée du président Ulysses S. GRANT en personne - celui-là même qui avait battu le Général LEE, le chef des Confédérés et gagné la guerre de sécession (American civil War) quelques années auparavant (1865). Pendant ce temps, Loomis avait reçu le brevet N° 129,971 intitulé "Improvement on Telegraphing" (améliorations dans le télégraphe) pour son système "sans fil". (Compiled from various sources)
Original excerpt 1 : « UNITED STATES PATENT OFFICE - MAHLON LOOMIS OF WASHINGTON, DISTRICT OF COLUMBIA. - IMPROVEMENT IN TELEGRAPHING. - Specification forming part of Letters Patent No. 129,971, dated July 30, 1872.To all whom it may concern: Be it known that I, MAHLON LOOMIS, dentist, of Washington, District of Columbia, have invented or discovered a new and improved Mode of Telegraphing and of Generating Light, Heat, and Motive-Power; and I do hereby declare that the following is a full description thereof. The nature of my invention or discovery consists, in general terms, of utilizing natural electricity and establishing an electrical current or circuit for telegraphic and other purposes without the aid of wires, artificial batteries, or cables to form such electrical circuit, and yet communicate from one continent of the globe to another. To enable others skilled in electrical science to make use of my discovery, I will proceed to describe the arrangements and mode of operation. As in dispensing with the double wire, (which was first used in telegraphing,) and making use of but one, substituting the earth instead of a wire to form one-half the circuit, so I now dispense with both wires, using the earth as one-half the circuit and the continuous electrical element far above the earth's surface for the other part of the circuit. I also dispense with all artificial batteries, but use the free electricity of the atmosphere, co-operating with that of the earth, to supply the electrical dynamic force or current for telegraphing and for other useful purposes, such as light, heat, and motive power. As atmospheric electricity is found more and more abundant when moisture, clouds, heated currents of air, and other dissipating influences are left below and a greater altitude attained, my plan is to seek as high an elevation as practicable on the tops of high mountains, and thus penetrate or establish electrical connection with the atmospheric stratum or ocean overlying local disturbances. Upon these mountaintops I erect suitable towers and apparatus to attract the electricity, or, in other words, to disturb the electrical equilibrium, and thus obtain a current of electricity, or shocks or pulsations, which traverse or disturb the positive electrical body of the atmosphere above and between two given points by communicating it to the negative electrical body in the earth below, to form the electrical circuit. I deem it expedient to use an insulated wire or conductor as forming a part of the local apparatus and for conducting the electricity down to the foot of the mountain, or as far away as may be convenient for a telegraph-office, or to utilize it for other purposes. I do not claim any new key-board nor any new alphabet or signals; I do not claim any new register or recording instrument; but What I claim as my invention or discovery, and desire to secure by Letters Patent, is-- The utilization of natural electricity from elevated points by connecting the opposite polarity of the celestial and terrestrial bodies of electricity at different points by suitable conductors, and, for telegraphic purposes, relying upon the disturbance produced in the two electro-opposite bodies (of the earth and atmosphere) by an interruption of the continuity of one of the conductors from the electrical body being indicated upon its opposite or corresponding terminus, and thus producing a circuit or communication between the two without an artificial battery or the further use of wires or cables to connect the co-operating stations. MAHLON LOOMIS. »
French translated excerpt 2 : « Je soussigné, MAHLON LOOMIS, dentiste, Washington, District de Colombie, ai inventé ou ai découvert un nouveau moyen pour télégraphier et de produire de la lumière, de la chaleur, et de la force motrice; et j'affirme par la présente que ce qui suit en est une description complète. La nature de mon invention ou découverte consiste, d'une façon générale, dans l’utilisation de l'électricité normale et dans la mise en place d’un courant électrique ou un circuit télégraphique sans aide de fils, de batteries artificielles ou de câbles, pour établir un circuit électrique qui communique d'un continent du globe à l'autre. [...] » (extrait Patent n° 129,971, 30 juillet 1872)
Urls : http://www.smecc.org/mhlon_loomis.htm (last visited ) http://dspt.perso.sfr.fr/LOOMIS.htm (last visited ) http://earlyradiohistory.us/129971.htm (last visited )

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