Page:Proceedings of the Royal Society of London Vol 60.djvu/389

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Profs, J. A. Fleming and J. Dewar. On the

The resultant charge having been measured on the ballistic galvanometer, the condenser was lifted out into the cold gaseous oxygen lying on the surface of the liquid oxygen, and before the condenser had time to alter its form by rising in temperature, the same process was repeated with the dielectric changed to gaseous oxygen at —182°C.

The following Table I shows the observed ballistic throws, all reduced to their equivalents at one common charging pressure of 100 volts

Table I.—Observations to Determine the Dielectric Constant of Liquid Oxygen.

P otential to w hich the condenser was charged in volts. Ballistic throw in cm., corresponding to 10 charges of th e sm all condenser. Ballistic throw , reduced to correspond to 10 charges of the small condenser at 100 volts. Exp. I .— Condenser at 103 *3 7*7 7*45 ordinary tem perature, 103*2 7*75 7*51 15° C. 103 *2 7 *75 7*51 Exp. I I .— Condenser in 103 *15 11*3 10 *96 liquid oxygen at —182° 103 1 11*25 10*91 C. 103*1 11 *27 10 *93 103 *0 11 *27 10*94 Exp. I I I . —- Condenser 101 *3 7 *65 7*55 in cold oxygen gas 101*2 7*6 7*51 above the liquid oxy­ 101*2 7 *6 7*51 gen a t —182c C. 101 *2 7*58 7*49 101*2 7*56 7*51 Exp. IY . — Condenser 101 *3 10 *9 in liquid oxygen. 101*2 10*85 10 *72 J b d * Exp. Y .—Condenser in 101*3 7 *60 7*50 cold oxygen gas above 101*3 .7 *60 7*50 the liquid oxygen. 101*3 7*58 7*48 101 *3 7 '5 7 7*47 Exp. Y I. — Condenser 101 *4 11*1 10 *95 in liquid oxygen. 101 *3 11 *0 10*86 101 *3 10*95 10*81 101*3 11 *0 10*86 M ean ballistic throw in gaseous oxygen = 7*502 = O'. M ean ballistic throw in liquid oxygen = 10*903 = 0.