Signalling through space without wires : being a description of the work of Hertz & his successors . Fig. 49 (p. 762, The Electrician, Vol. XLIII.).—Marconi Signalling Mast at Dover Town Hall. TELEGRAPHIC APPLICATIONS. 69. Fig. 50 (Fig. 1, p. 7, The Electrician, Vol XLIII.).—Mast at South Forelandfrom which Signals went to a similar Mast at Witnereux, near Boulogne. 70 SIGNALLING WITHOUT WIRES. Concerning the receiving apparatus there is little to besaid, since it is in essence the same as that which has alreadybeen described. It consists of a coherer of the plug tubepattern, something like th
Signalling through space without wires : being a description of the work of Hertz & his successors . Fig. 49 (p. 762, The Electrician, Vol. XLIII.).—Marconi Signalling Mast at Dover Town Hall. TELEGRAPHIC APPLICATIONS. 69. Fig. 50 (Fig. 1, p. 7, The Electrician, Vol XLIII.).—Mast at South Forelandfrom which Signals went to a similar Mast at Witnereux, near Boulogne. 70 SIGNALLING WITHOUT WIRES. Concerning the receiving apparatus there is little to besaid, since it is in essence the same as that which has alreadybeen described. It consists of a coherer of the plug tubepattern, something like that depicted on page 23, but exces-sively reduced in size, the glass tube being the size of a quill,the two silver plugs close together separated only by a veryfew nickel filings. This tube is mounted so that it can bestruck after each signal by a light electric hammer worked bya current from a local battery switched on by a Siemenspolarised relay, which is itself actuated by the coherer the coherer receives a signal the same current thatworks the tapper works also the Morse instrument standingon the table alongside, and records a short or a long signal onthe tape. The coherer with its tapper, the
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Keywords: ., bookcentury1900, bookdecade1900, bookidsi, booksubjectelectricity
