Signalling through space without wires : being a description of the work of Hertz & his successors / by Oliver J. Lodge.

  • Oliver Lodge
Date:
[1900]
Catalogue details

Licence: Public Domain Mark

Credit: Signalling through space without wires : being a description of the work of Hertz & his successors / by Oliver J. Lodge. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    gradually and slowly exert a paralysing or obstructive action on the portion of the nerve to which they are applied, so that the nerve impulse excited by the feeble just perceptible TJo^n volts stimulus above is gradually throttled on its way down to the muscle, and remains so throttled for a time varying from a few minutes to an hour after the cessation of the violence. [I did not show this experiment at the lecture.] Air Gap and Electroscope charged by Glass Rod and discharged by tJie Wave Impulse from a moderately distant Sphere excited by Coil. Among trigger methods of detecting electric radiation, I have spoken of the Zehnder vacuum tubes; another method is one used by Boltzmann.* A pile of several hundred volts Fia. 16.—Air gap for Electroscope. Natural size. The bottom plate is connected to, and represents, the cap of an electroscope; the knob above it, mentioned in text, is the polished end of the screw, whose terminal is connected with the case of the instrument or earth. The electroscope being charged to the verge of overflow, the impact of weak electric waves collected by a bit of wire sticking up from the left-hand binding screw precipitates the collapse of the leaves. is on the verge of charging an electroscope through an air gap just too wide to break down. Very slight electric surgings precipitate the discharge across the gap, and the leaves diverge. I show this in a modified and simple form. On the cap of an electroscope is placed a highly polished knob or rounded end connected to the sole, and just not touching the cap, or, rather, just not touching a plate connected with the cap (Fig. 16), the distance between knob and plate being * Weid. Arm., 40, p. 399.