Cyclopedia of applied electricity: a general reference work on direct-current generators and motors, storage batteries, electrochemistry, welding, electric wiring, meters, electric light transmission, alternating-current machinery, telegraphy, etc, Volume 7 (Google eBook)

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American technical society, 1913 - Electrical engineering
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Page 172 - ... 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...
Page 157 - This velocity is so nearly that of light, that it seems we have strong reason to conclude that light itself (including radiant heat, and other radiations if any) is an electromagnetic disturbance in the form of waves propagated through the electromagnetic field according to electromagnetic laws.
Page 171 - 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,...
Page 172 - 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...
Page 171 - 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, cables, or any of our present costly appliances. Granted a few reasonable postulates, the whole thing comes well within the realms of possible fulfilment.
Page 239 - In view of the foregoing, it is not surprising to find that early experiments in radiotelephony were directed almost exclusively toward a solution of the problem of an efficient transmitting apparatus.
Page 149 - G is the galvanometer ; ww, are the wires along the banks, connected with copper plates,/, g, h, i, which are placed in the water. When this arrangement is complete, the electricity, generated by the battery, passes from the positive pole, p, to the plate h, across the river through the water to plate i, and thence around the coil of the galvanometer to plate /, across the river again to plate g, and thence to the other pole of the battery, N.
Page 2 - ... sheaves similar to the method described for the horizontal hydraulic, and the motor, of course, is reversible. One of the principal features of this type of machine was the construction of the nut which traveled on this large screw. It was supplied with steel balls on the pull side of the screw, and they ran close together in single file through a channel, which carried them around through the threads of the nut and caused them to return to the other end of the same after they had passed through....

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