Electricity from a Nernst Filament. 255, 
TABLE XIII. 
1 ampere through magnet=59 lines per sq. cm. 
a | Patestial Resistance in Series Wome hae rece | Current, Percentage} 
| otential. Sah Bilamient: | ee Say eee | igen: on. Doped = 
mm. | amperes. | 
0005 | —400 (|16¢.p.lamp+80 ohms | (131 | 
7 Se Te Tae Wo tate 
| 6:2 88 | 88 °/, 
(A) 4 Mean=1382 | 7-2 48 | 6] 
| 9s 9°6 11 po O2 
15°5 seh 8 60x 10°} 
| 133 
—600 (16 cp. lamp+80ohms/| /144 
| | Ls. NETRING Vien isch 
: C) SAS 8: 83 49 0 
/ ( 4 Mean=142°5. 114 17 Bice /o 
| ESP TOA WSs. 5:0 xe 
\ 141 | | 
—400 16 c.p. lamp. (533 | | 
| | a2 2 UI & erate 
59 451 14 5), 
(@.) 4 Mean=518 6-4 334 ee 
| 8-2 93 82 
| 155 iio ee OF 6:0 x 10°) 
—400 | 119 ohms ( 6200 | | 
58 5950 0°5 °/, 
6°5 4700 Pi 
i ) 4 Mean=5975 82 1500 75 
| 11°5 350 94 | 
} | 155 | 150 98 | 56x 10° 
; (5750 
s | 
j 
Mean value of ee =5'6d x 108 
m 
The points where the curves cut the axis of the current 
give the values of H taken to calculate e/m. The two sets 
of observations (A) and (A’) lie practically on the one 
curve A. The other curve B for a potential of —400 volts 
does not quite coincide with the curve A. This is probably 
due to the current dealt with in set (B) being very much 
larger than those in the sets (A) and (A’). The mean value 
of e/m found, namely 5°65 x 10°, agrees sufficiently closely 
with the values obtained by Prof. J. J. Thomson for the 
negative ions discharged from a plate illuminated by ultra- 
violet light and from a carbon filament (7°3 x 10° and 8°7 x 108 
