A History of Wireless Telegraphy, 1838-1899: Including Some Bare-wire Proposals for Subaqueous TelegraphsDodd, Mead & Company, 1900 - 325 páginas |
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A History of Wireless Telegraphy, 1838-1899: Including Some Bare-wire ... John Joseph Fahie Visualização integral - 1899 |
A History of Wireless Telegraphy: Including Some Bare-wire Proposals for ... John Joseph Fahie Visualização integral - 1901 |
A History of Wireless Telegraphy, 1838-1899: Including Some Bare-wire ... John Joseph Fahie Visualização integral - 1900 |
Palavras e frases frequentes
aërial apparatus arrangement battery cable cells centimetres charge coherer communication condenser conducting conductors connected copper wire Daniell cell detector diameter discharge distance disturbance Dundee earth ebonite effect Elec electric currents electric waves electrical oscillations Electrician electro-magnetic employed ether ethereal waves exciter experiments feet figure filings Flat Holm galvanometer Guglielmo Marconi gutta-percha Hertz imperfect contact inch increase induction coil Inst iron Leclanché cells length Leyden jar light lighthouse Lindsay magnetic Marconi means ments messages method microphone miles Morse Muckle Flugga needle obtained ohms ordinary paper parallel pass poles possible powder practical Preece preferably present Prof radiation receiving instrument reflector relay resistance Ruhmkorff coil secondary self-induction sensitive tube shore shown signals similar space sparks spheres station surface tele telegraph telephone terminals tion transmitting instrument trembler tricity tube or contact tube or imperfect vibrations Willoughby Smith wire wireless telegraphy yards
Passagens conhecidas
Página 300 - Invention, and in what Manner the same is to be performed, to be particularly described and ascertained in and by the following Statement...
Página 319 - Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is (d).
Página 198 - ... which will easily pass through buildings and fogs, to those long waves whose lengths are measured by tens, hundreds, and thousands of miles; secondly, more delicate receivers which will respond to wavelengths between certain defined limits and be silent to all others; thirdly, means of darting the sheaf of rays in any desired direction, whether by lenses or reflectors, by the help of which the sensitiveness of the receiver (apparently the most difficult of the problems to be solved) would not...
Página 199 - This is no mere dream of a visionary philosopher. All the requisites needed to bring it within the grasp of daily life are well within the possibilities of discovery, and are so reasonable and so clearly in the path of researches which are now being actively prosecuted in every capital of Europe, that we may any day expect to hear that they have emerged from the realms of speculation into those of sober fact.* . . . The purposes and problems of radiotelegraphy are admirably stated in the above.
Página 197 - Here is unfolded to us a new and astonishing world — one which it is hard to conceive should contain no possibilities of transmitting and receiving intelligence. Rays of light will not pierce through a wall, nor, as we know only too well, through a London fog. But the electrical vibrations of a yard or more in wave-length of which I have spoken will easily pierce such mediums, which to them will be transparent. Here, then, is revealed the bewildering possibility of telegraphy without wires, posts,...
Página 198 - What, therefore, remains to be discovered is, firstly, simpler and more certain means of generating electrical rays of any desired wave-length, from the shortest, say of a few feet in length, which will easily pass through buildings and fogs, to those long waves, whose lengths are measured by tens, hundreds, and thousands of miles; secondly, more delicate receivers, which will respond to wave-lengths between certain defined limits, and be silent to all others ; thirdly, means of darting the sheaf...
Página 258 - Optics is a branch of electricity. Outstanding problems in optics are being rapidly solved, now that we have the means of definitely exciting light with a full perception of what we are doing and of the precise mode of its vibration. It remains to find out how to shorten down the waves — to hurry up the vibration until the light becomes visible. Nothing is wanted but quicker modes of vibration. Smaller oscillators must be used — very much smaller — oscillators not much bigger than molecules....
Página 4 - It only holds good, however, for small distances ; and it must be left to the future to decide whether we shall ever succeed in telegraphing at great distances without any metallic communication at all. My experiments prove that such a thing is possible up to distances of 50 feet. For...
Página 136 - The invention all admired, and each, how he To be the inventor missed ; so easy it seemed Once found, which yet unfound most would have thought Impossible...
Página 260 - Solar radiation consists of waves of all sizes, it is true ; but then solar radiation has innumerable things to do besides making things visible. The whole of its energy is useful. In artificial lighting nothing but light is desired ; when heat is wanted it is best obtained separately by combustion. And so soon as we clearly...