740 Prof. Townsend and Mr. Hurst on the 
The electric force X to which the currents g correspond is 
given in volts per eeummoalare: The numbers n are calculated 
= ,aand £ being chosen 
so that the formula oy agree with the currents at three 
different distances, ) being taken as unity. 
It will be seen that the formula is in agreement with the 
currents over the whole range of distances. The values of a 
log a— log B 
ae 
the foot of the tables, also the quantities X xa and the 
sparking potential V determined experimentally, for the 
distance a between the plates. 
from the formula N= No 
obtained from the equation a=—> are given at 
Air, Pressure 2 mms. 
ase ASE | 2. 4 6 | ‘8, 
Paso! Wp ede alt. 4-67 22-2 110 800 
ey iy tlieeuis 
ott Soe | a7 22:1 110 820 
B= 0070 Mere | | 
hive a= 91, oxX=481, V=498. 
Air, Pressure 4 mms. 
dy. capes | 1 2, | 3 4 
a | 
HX I050! Gg ieseals 2 | 467 224 |-- 11% 4933 
eae I | 4-67 29-2 111 | 883 
a=454, axX=477,_V=480.. 
Air, Pressure 4 mms. 
5 eae a 2 3, | 4 | 5. | 6 | 7 8 
X= 700" g°..5...- 512 | 14-4 96-7 | 61 h 148 | 401 | 1500 | 
eS aaron of 5:13 ane ae vs 62 | 149 he! 309 || 1544 tt 
| eayy iS 
| 
