An account of some new experiments in electricity / [William Henly].

  • William Henly
Date:
1774
Catalogue details

Licence: Public Domain Mark

Credit: An account of some new experiments in electricity / [William Henly]. Source: Wellcome Collection.

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    [ «8 ] longeft, many feet, in length. When thofe jars were difcharged through the iron bar before-men¬ tioned, together with a fmall chain, three quar¬ ters of a yard in length ; the whole chain was il¬ lumined, and covered throughout with beautiful rays, like briftles, or golden hair. Having placed a large jar in contact with my prime conductor, I affixed to the coating of it an iron chain, which 1 alfo connected with a plate of metal, on which I intended to make the difeharge by my dis¬ charging-rod, tab. xiii. fig. 9. This done, I hooked another chain, much longer, and of brafs, to the oppofite fide of the jar, and brought the end of it within eight inches and an half of the metal plate. In contaft with this end, 1 laid a fmall oak-ftick, eight inches long, which 1 co¬ vered with faw-duft of fir-wood. On making the difeharge upon the plate, both the chains were luminous through their whole lengths; as was alfo the faw-duft, which was covered by a ftreak of light, making a very pleafing appearance. I repeated the experiment feveral times. Perhaps, if I had ufed a bar of iron, inftead of the chain firft-fpoken of, there might have been no light upon the fecond chiin, or upon the faw-duft, ef- pecially as the eleftricity had half an inch of air to pafs through, before it reached the end of the ftick. But from this experiment may, I think, be inferred, the necefiity of making the conduftors, erefted as a fecurity to buildings, &c. from the damage of lightning, both of the beft materials, and of a very fufficient fubftance ; and, for this pur- pofe, perhaps nothing will be found fo proper as 4
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