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A History of Wireless Telegraphy (2nd edition, revised), J. J. Fahie, 1901, pages 6-10:


    While arranging, in 1883, the Edward Davy MSS., now in the library of the Institution of Electrical Engineers, the present writer discovered two passages which he at first took to have reference to some kind of telephonic relay; but on closer consideration it would appear that Davy had in view some contrivance based on the conjoint use of sound and electricity, much as Steinheil suggested the joint use of electricity and heat. The following are the passages to which I refer:--
    At the end of a long critical examination of Cooke and Wheatstone's first patent of June 12, 1837, he says: "I have lately found that there is a peculiar way of propagating signals between the most distant places by self-acting means, and without the employment of any conducting wires at all. It is to be done partly by electricity, but combined with another principle, of the correctness of which there can be no doubt. But until I know what encouragement the other 8 will meet with I shall take no steps in this, as it may happen there will be other rivals. To give you a general idea of it, a bell may be rung at the first station, and then in the next instant a bell will ring at the next station a mile off, and so on for an unlimited series, though there is nothing between them but the plain earth and air! At the termination of the series, the signais may be given in letters, as in the present contrivance."
    Again, in a paper of numbered miscellaneous memoranda, No. 20 reads as follows: "20. The plan proposed (101) of propagating communications by the conjoint agency of sound and electricity--the original sound producing vibrations which cause sympathetic vibrations in a unison-sounding apparatus at a distance, this last vibration causing a renewing wire to dip 9 and magnetise soft iron so as to repeat the sound, and so on in unlimited succession."
    It is not easy to say from these passages (which are all we could find on the subject) what plan Davy had in contemplation. In the first quotation he speaks of bells, for which we may read a powerful trumpet at one end, and a concave reflector to focus the sound at the other end; or some arrangement like the compressed-air telephone, proposed by Captain Taylor, R.N., in 1844; or the modern siren; or, in short, any means of producing sharp concussions of the air, such as were known in his day. Let us suppose he used any of these methods for projecting sound waves, then, at the focus of the distant reflector he may have designed a "renewing wire," so delicately poised as to respond to the vibration, and so close a local circuit in which was included the electro-magnetic apparatus for recording the sound, or for renewing it as required.
    In the second passage he speaks of something on the principle of the tuning-fork. Now, tuning-forks in combination with reflectors may be practicable for short distances, but it is difficult to see how their vibrations could be utilised, at the distance of a mile, for "causing a renewing wire to dip."
    However this may be, Davy's idea deserves at least this short notice in a history of early attempts at wireless telegraphy; for, although hardly possible of realisation with the apparatus at his command, it is perfectly feasible in these days of megaphones and microphones. As regards its practical utility, that is a question for the future, as to which we prefer not to prophesy. 10
    Davy's idea was probably the result of an incautious dose of the Auticatelephor of Edwards, which made a great stir a few years previously, and which, at first sight, might be taken to be a telegraph without apparently any connecting medium. We take the following announcement from the 'Kaleidoscope' of June 30, 1829 (p. 430):--


    "We have received several papers descriptive of a new and curious engine, with the above name, invented by Mr T. W. C. Edwards, Lecturer on Experimental Philosophy and Chemistry, and designed for the instantaneous conveyance of intelligence to any distance. After noticing some of the greatest inventions of preceding times, Mr Edwards undertakes to demonstrate clearly and briefly, in the work which he has now in the press, 11 the practicability and facility of transmitting from London, instantaneously, to an agent at Edinburgh, Dublin, Paris, Vienna, St Petersburg, Constantinople, the Cape of Good Hope, Madras, Calcutta, &c., any question or message whatever, and of receiving back again at London, within the short space of one minute, an acknowledgment of the arrival of such question or message at the place intended, and a distinct answer to it in a few minutes. In principle this engine is altogether different from every kind of telegraph or semaphore, and requires neither intermediate station nor repetition. In its action it is totally unconnected with electricity, magnetism, galvanism, or any other subtle species of matter; and although the communication from place to place is instantaneous, and capable of ringing a bell, firing a gun, or hoisting a flag if required, yet this is not effected by the transit of anything whatever to and fro; nor in the operation is aught either audible or visible, except to the persons communicating. It may be proper, however, to state that a channel or way must previously be prepared, by sinking a series of rods of a peculiar description in the ground, or dropping them in the sea; but these, after the first cost, will remain good for ages to come, if substantial when laid down." 12
    From the concluding words of this paragraph it would seem that the Auticatelephor was simply an application to telegraphy of pneumatic or hydraulic pressure in pipes--cautiously styled "rods of a peculiar description." On this supposition the last sentence may be paraphrased thus: "It may be proper, however, to state that a channel or way must previously be prepared, by laying down a continuous series of hollow rods or tubes under the ground or along the sea-bottom." If our supposition be correct, and if Edwards contemplated the use of compressed air, his proposal was certainly novel; but if he designed the use of compressed water, the idea was by no means new. Without going back to the old Roman plan of Æneas Tacticus, we have its revival by Brent and others towards the close of the last century, and the still more practical arrangements of Joseph Bramah in 1796, of Vallance in 1825, and of Jobard in 1827.

    8 That is, his chemical recording telegraph. See my 'History of Electric Telegraphy,' p. 379.
    9 I.e., causing a relay to close a local circuit containing an electro-magnet. Davy always spoke of the relay as the "renewer" or the "renewing wire" and by dip he meant to dip into mercury, or, as we say nowadays, to close the circuit
    10 Such a plan as Davy's was again suggested, in 1881, by Signor Senlicq d'Andres ('Telegraphic Journal,' vol. ix. p. 126), who, however, proposed to use, instead of a renewing wire or relay, the mouthpiece of a microphonic speaker, rendered more sensitive by a contact lever with unequal arms. Mr A. R. Sennett has also worked at the idea in more recent years. His method is very clearly described in the 'Jour. Inst. Elec. Engs.,' No. 137, p. 908.
    11 In 1883 we searched for this book in vain. Under the name T. W. C. Edwards we found in the British Museum Catalogue no less than twenty entries of translations from Greek authors, and of Greek and Latin grammars, &c.; but nothing to show that the writer was either a natural philosopher or a chemist.
    12 See also the 'Mechanics' Magazine,' vol. xiii., First Series, p. 182.
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