Signalling through space without wires : being a description of the work of Hertz & his successors . e scale. If a coherer be attached by a side wire to the gas pipes, andan electrophorus spark be given to either the gas pipes or thewater pipes or even to the hot-water system in any other roomof the building, the coherer responds. It is surprising how WORK OF HERTZ LECTURE. 33 far these impulses can be felt along an ordinary uninsulatedwire or other conductor. In fact, when thus connected to gas-pipes one day when Itried it, the spot of light could hardly keep still five there
Signalling through space without wires : being a description of the work of Hertz & his successors . e scale. If a coherer be attached by a side wire to the gas pipes, andan electrophorus spark be given to either the gas pipes or thewater pipes or even to the hot-water system in any other roomof the building, the coherer responds. It is surprising how WORK OF HERTZ LECTURE. 33 far these impulses can be felt along an ordinary uninsulatedwire or other conductor. In fact, when thus connected to gas-pipes one day when Itried it, the spot of light could hardly keep still five there was a distant thunderstorm, or whether it wasonly picking up telegraphic jerks, I do not know. The jerkof turning on or off an extra Swan lamp can affect it whensensitive. I hope to try for long-wave radiation from theBun, filtering out the ordinary well-known waves by a black-board or other sufficiently opaque substance. [I did not succeed in this, for a sensitive coherer in anoutside shed unprotected by the thick walls of a substantialbuilding cannot be kept quiet for long. I found its spot of. Fig. 19b.—A Portable Detector, B the Collecting Wire. light liable to frequent weak and occasionally violent excursions,and I could not trace any of these to the influence of the were evidently too many terrestrial sources of disturb-ance in a city like Liverpool to make the experiment dont know that it might not possibly be successful in someisolated country place; but clearly the arrangement must behighly sensitive in order to succeed.] We can easily see the detector respond to a distant sourceof radiation now, viz., to a 5in. sphere placed in the librarybetween secondary coil knobs; separated from the receiver,therefore, by several walls and some heavily gilded paper, aswell as by 20 or 30 yards of space (Fig. 19.) Also I exhibit (Fig„ 19b) a small complete detector made bymy assistant, Mr. Davies, which is quite portable and easily set 34 SIGNALLING WITHOUT
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Keywords: ., bookcentury1900, bookdecade1900, bookidsi, booksubjectelectricity
