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Signalling through space without wires : being a description of the work of Hertz & his successors . coherer circuit. The objectof the box is, of course, the protection of the coherer fromundesired disturbances, exactly as described on page 34,and the collecting wire has the function there describedlikewise. The electric tapper-back is also mentioned on page 31, butnot as being operated through a relay by the coherer circuitsown current. This last improvement seems to have beendevised and employed by Prof. Popoff at Cronstadt in 1895(see Fig. 42). No doubt it was arrived at independently again
Signalling through space without wires : being a description of the work of Hertz & his successors . coherer circuit. The objectof the box is, of course, the protection of the coherer fromundesired disturbances, exactly as described on page 34,and the collecting wire has the function there describedlikewise. The electric tapper-back is also mentioned on page 31, butnot as being operated through a relay by the coherer circuitsown current. This last improvement seems to have beendevised and employed by Prof. Popoff at Cronstadt in 1895(see Fig. 42). No doubt it was arrived at independently againby Mr. Marconi and the telegraph officials who assisted himin his early experiments in this country. The other box shown in Fig. 51 is probably a stand-byin case of accident. It is difficult to imagine a simpler contrivance, and itappeared to work at Dover dependably, the messages comingout slowly in ordinary dots and dashes, the torrent of sparksbeing sufficiently rapid not to necessitate the breaking up ofthe dash into a series of dots. The sluggishness of the Morse TELEGRAPHIC APPLICATIONS 71. 72 SIGNALLING WITHOUT WIRES. instrument or the relay, or the circuit as a whole, enabledthis excellent result to be attained with apparent ease. A diagram of Marconis connection of sensitive tube to therelay and tapper-back and Morse instrument, where W repre-sents the elevated wire, is given in Fig. 52.
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Keywords: ., bookcentury1900, bookdecade1900, bookidsi, booksubjectelectricity