File:The dictionary of arts, sciences and manufactures embracing in all nearly three thousand articles on arts and sciences (1859) (14744566596).jpg

Identifier: dictionaryofarts02smit (find matches)
Title: The dictionary of arts, sciences and manufactures ... embracing in all nearly three thousand articles on arts and sciences
Year: 1859 (1850s)
Authors: Smith, James, author of the Panorama of science and art
Subjects: Technology Industrial arts
Publisher: Boston, Phillips, Sampson, and Co.
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Smithsonian Libraries

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cal jars or batteries, the electric fluidpasses in the greatest quantity through the best conductors, andby the shortest course. Thus, if a chain and a wire, communi-cating with the outward coating, be presented to the knob of ajar, the greater part of the charge will pass by the wire, becausethe chain is the worse conductor, from the want of perfect con-tinuity in the links. When the discharge is made by the chainonly, sparks are seen at every link, which would not happen ifthey were in contact: and as it requires considerable force instretching the chain, before the sparks cease to be seen, aproof is thus obtained that a strong power of repulsion is tobe overcome, before the contact of bodies ensues. * The Discharging Rod. The common discharging rod, which is represented at fig. 8,pi. I, consists of a glass handle, M, cemented into a brasssocket, N. Two wires, PP, slightly incurvated towards eachother, are jointed into the brass socket IN, by which means K I, K (I.k I C IT V, l-1. I
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ELECTRICITY. 215 Commou discharger.—Universal dischargee their extremities may be brought together, or separated as faras required. The wires are pointed at the extremities, butbeing screwed also at a little distance from the point, each ofthem admits of a small sphere or knob being screwed upon it. To discharge a jar with this rod, the wires are opened tilltheir extremities will reach from the knob of the jar to its out-side coating, and the discharge immediately follows the esta-blishment of the communication between these two parts ; abattery is discharged in the same manner, by touching, withone limb of the instrument^ the hook, or the wire attached tothe hook, in contact with the outside coatings, and with theother limb touching one of the wires communicating with theinside coatings. In making the discharge, the electricity only passes throughthe metallic part of the instrument, and therefore the personwho holds by the glass handle, receives no shock. Somepart of it, however, m

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