Lectures on electricity / by James Ferguson, F.R.S.

  • James Ferguson
Date:
1825
Catalogue details

Licence: Public Domain Mark

Credit: Lectures on electricity / by James Ferguson, F.R.S. Source: Wellcome Collection.

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    inch from it, the condensed lire will snap from the con- ductor in large sparks to his knuckle ; and give him rather a disagreeable than painful sensation : and as fast as the fire lies to his knuckles, it runs off by his arms and body to the ground. If he holds his knuckle very near the conductor, he will not feel the fire so sharp, because he has it more gradually, and in a con- stant small stream ; and if he puts his finger upon the conductor, he will not feel the fire in the least, although he receives it just as fast from the conductor as it is given thereto by the globe. EXPERIMENT XVIII. Electric Sparks taken from the human body. 59. Having warmed the glass-footed stool (§ 28) a little by the fire, and wiped it all over to clear it of dust, set it upon the floor, and let any person stand upon it, holding one end of a chain (or rather of a wire,) the other end of which is hooked to the prime conductor ; the chain or wire being held up at some distance from the table, and no chair, table, or person in the roon being within a foot of the person who stands on the stool. Then turn the glass globe of the machine by the winch, and all the fire that the prime conductor receives from the globe will be conducted from it by the chain or wire to the person on the stool, and he will be strongly elec- trified, without feeling any thing from the fire he re- ceives, unless some person who stands on the floor touches him any where with a finger ; and if he does, all the fire will snap against his finger from the electri- fied person, and both these persons will feel it smartly but it will do no harm to either of them. By this method, all the electric fire, which a person receives while he stands on the stool, may be drawn off from any part of his body that is touched by a person standing on the ground. But the person who touches, should