Observations on a series of electrical experiments / By Dr. Hoadly, and Mr. Wilson.

  • Benjamin Hoadly
Date:
1759
Catalogue details

Licence: Public Domain Mark

Credit: Observations on a series of electrical experiments / By Dr. Hoadly, and Mr. Wilson. Source: Wellcome Collection.

    35/96 page 31
    hand, the brafs and the electrical fluid that is in the vacuum. But that no doubt may remain in an enquiry of fo delicate a nature, I will propofe making the experiment in a more accurate manner. Every one knows that a bar of iron, fufpended by filk firings in the air, may be kept equally electrified, or very nearly fo, for any length of time, by the electri¬ fying machine’s being kept equally in motion, during that time. Now if inftead of approaching an excited tube of glafs (which is continually lofing its power) to the exhaufled tube, as I did before ; I now approach the exhaufled tube to the electrified bar (whofe electrifying force is con- flantly kept up at the fame degree by the machine) to fuch a particular diflance, as to make the lucid appear¬ ance begin; and then keep it there fleady : I gain this advantage, that it continues during the whole time I keep it thus fleady at one certain diflance, expofed to one and the fame degree of force in the electrified bar, or very nearly fo. And on trying the experiment thus, I found that the lucid appearance continues only for a limited time; and if the tube was to be held fo ever fo long, there would be no return of that appearance: but on removing the exhaufled tube from the bar, the light returns again immediately, fhooting then from the brafs and hand to that part of the inner furface of the tube, that had been nearefl to the bar. No
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