Signalling through space without wires : being a description of the work of Hertz & his successors (1900)
Lodge, Oliver, Sir, 1851-1940, Hertz, Heinrich, 1857-1894 · London : "The Electrician" Printing and Publishing Company, Limited · leaf 49
a small whitewashedchamber well supplied with looking-glasses; nor have I eversucceeded in getting clear concentration with this zone-platehaving Newtons rings fixed to it in tinfoil. The coherer, atany rate in a room, does not seem well adapted to interferenceexperiments; it is probably too… … Fig. 22.—Zone-plate of Tinfoil on Glass. Every circular strip is of area equal to central space. waves and the measure of their length. There was immenseinterest in Hertzs time, because then the wave characterof the radiation had to be proved; but every possible kind ofwave must give interference…
Electric waves · Telegraph, Wireless · Electricity · Wireless Technology
Internet Archive · Medical Heritage Library · Public Domain Mark 1.0. Free to use for anything.
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