452 
DPv. W. MANSERGH VARLEA ON THE PHOTO-ELECTRIC 
Table IX. 
Potential to ■which 
platinum is charged 
in cells. 
(1 cell = 2 • 1 volts.) 
Current from platinum surface in electrometer 
scale (Uvisions in To seconds in— 
Air. 
H,. 
CO,. 
12 millims. 
12 millims. 
12 millims. 
20 
36 
39 
58 
40 
— 
51 
— 
60 
51 
72 
83 
80 
— 
128 
— 
100 
90 
301 
163 
120 
128 
— 
266 
140 
208 
— 
— 
Note .— 1 volt P.D. between the electrometer quadrants corresponded to a 
deflection of G7 divisions. 
The })hoto-electric currents in carbon monoxide were also compared with those in 
air, the results at two typical pressures, viz., 20 millims. and 0’045 millim., being 
given in the following Table X. The zinc electrode was situated 3 millims. behind 
the gauze, and I volt P. D. between the electrometer quadrants corresponded to a 
deflection of 72 divisions. Tlie carbon monoxide was prepared from sodium formate 
and strong sulphuric acid, and was v/ashed and dried befoi'e allowing it to enter the 
leak aj)paratus. 
Table X. 
Potential to which 
the zinc is charged 
in cells. 
(1 cell = 2 ■ 1 volts.) 
Current from zinc surface in electrometer scale divisions 
in 10 seconds in— 
Air. 
CO. 
Air. 
CO. 
20 millims. 
20 millims. 
0-045 millim. 
0-045 millim. 
S 
t 
92 
73 
144 
Ill 
20 
144 
124 
182 
154 
60 
212 
170 
218 
173 
100 
263 
203 
216 
169 
140 
351 
258 
— 
— 
160 
475 
-- 
-- 
— 
180 
— 
394 
214 
170 
These results are ^dotted in tig. 13. 
