Notices of the proceedings at the meetings of the members of the Royal Institution of Great Britain with abstracts of the discourses . could be exhausted through thestopcock / if desired, e was a drying bulb,containing phosphoric anhydride. The wirea passed air-tight through the brass cap g,cemented on to the neck h of b. h was madeof lead glass, on account of the superior insula-Fig. 2. ting qualities of this kind of glass. The cap g carried a brass strip h, to which the goldleaf I was attached. The whole was surrounded by a vessel m, asshown, n was an iron wire, attached to a platinum wire o
Notices of the proceedings at the meetings of the members of the Royal Institution of Great Britain with abstracts of the discourses . could be exhausted through thestopcock / if desired, e was a drying bulb,containing phosphoric anhydride. The wirea passed air-tight through the brass cap g,cemented on to the neck h of b. h was madeof lead glass, on account of the superior insula-Fig. 2. ting qualities of this kind of glass. The cap g carried a brass strip h, to which the goldleaf I was attached. The whole was surrounded by a vessel m, asshown, n was an iron wire, attached to a platinum wire o sealedthrough the glass. The iron wire could be brought into contactwith % by means of an external magnet, in order to charge the could be exhausted through the stopcock and dried by meansof the phosphoric anhydride contained in q. The position of thegold leaf was read by a microscope with micrometer eye-piece, focussedupon it. Before making an experiment, the insulation, which is all-im-portant, was tested, m was permanently exhausted, and the stopcockp closed, b was also exhausted for the time, and a charge given to. on Some Recent Investigations on Electrical Conduction. 297 the brass strip k, so that the leaf I diverged. It was found that theleaf moved over less than } of a scale division in the course of threehours. As soon as any air was admitted into b, a leakage of electricityfrom the wire a was observed. The following table gives the results, with various materials:— Material of Cylinder. Zinc ....Phosphoric acid on glass .Aluminium Silver, chemically deposited Copper oxide . Copper .... Tinfoil, 1st sample .„ 2nd sample . Platinum, 1st sample„ 2nd sample„ 3rd sample Uranium nitrate Current, in scaledivisions per hour. Strongest radium preparations 1-21-31-41-6 1- 7 2- 32-3332-02-93*9 12,0001,200,000,000 The number for uranium nitrate was obtained by cementing asmall piece of the substance on to the inner wall of the cylinder, anddetermining th
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Keywords: ., bookauthorroyalins, bookcentury1800, bookdecade1850, bookyear1851
