Signalling through space without wires : being a description of the work of Hertz & his successors . terminating at the topin a small conductor, which is usually made of wire netting,and is suspended from an insulating rod. The lower end olthis elevated wire passed into the building through anaperture, and was connected to one terminal of the usualRuhmkorff coil, the other terminal of which was signalling key was of the simplest description, being TELEGRAPHIC APPLICATIONS. 67 nothing more than a well-insulated Morse key worked byhand and causing a make-and-break in the primary circ
Signalling through space without wires : being a description of the work of Hertz & his successors . terminating at the topin a small conductor, which is usually made of wire netting,and is suspended from an insulating rod. The lower end olthis elevated wire passed into the building through anaperture, and was connected to one terminal of the usualRuhmkorff coil, the other terminal of which was signalling key was of the simplest description, being TELEGRAPHIC APPLICATIONS. 67 nothing more than a well-insulated Morse key worked byhand and causing a make-and-break in the primary circuit ofthe coil. The ordinary trembling break of the induction coilwas at work in the usual way, so that while the signalling keywas depressed continuously there was a torrent of sparksbetween the knobs of the secondary. This method of signal-ling was identical with that employed by everyone since thetime of Hertz, except that, instead of connecting the secondaryterminals to two insulated plates, one was now connectedto earth and the other to a small insulated conductor atconsiderable Fig 48 (Fig. 11 of Prof Slabys book on Spark Telegraphy). From this mast in the town of Dover (Fig. 49) signalscould be sent to another loftier mast at the South Foreland(Fig. 50), where it is itself elevated by chalk cliffs far abovethe sea. From this South Foreland station, which wassimilar in all essential respects to the Dover station, exceptthat its elevation was greater, messages could be sent andreceived to and from a station near Boulogne, on the coast ofFrance, and to and from the East Goodwins lightship. Thesignalling was slow, but appeared dependable, and thesimplicity of all the arrangements was remarkable (Fig. 51). f2 68 SIGNALLING WITHOUT WIRES.
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Keywords: ., bookcentury1900, bookdecade1900, bookidsi, booksubjectelectricity
