1896-97.] Experiments on Electric Properties of Uranium. 425 
coatings of A. Curve b coves the results obtained with the smaller 
piece of uranium in the glass bulb. 
§ 32. Leakage in other gases at ordinary pressure. 
.We have also observed the rate of leaks in hydrogen, oxy- 
gen, and carbonic acid at ordinary pressure at different volt- 
ages. The glass bulb referred to in §§ 30 and 31 was used for this 
purpose. The voltages were obtained by connecting the zinc to 
one terminal of a battery, and the other terminal to sheaths. 
The uranium was connected to the insulated terminal of the 
electrometer. While the connection between the battery and the 
zinc was being made the uranium was put in metallic connection 
with the case of the electrometer ; afterwards it was disinsulated, 
and the deviation in the electrometer observed per minute for a 
number of minutes. The following results were obtained for these 
Voltage per 
2 mins. 
2, 
HYDROGEN. 
Leakage per minute 
in scale divisions. 
32 
4 
37 
22 
39 
34 
38 
100 
39 
135 
38 
4 
OXYGEN. 
125 
96 
. 
157 
4 
CARBONIC ACID. 
94 
95 
* 
167 
238 
« • • 
183 
255 
a * 
180 
2900 
• 
Discharge by sparking. 
[Sensibility of electrometer 140 sc. div. per volt.] 
The results given for these three gases are comparable to the 
second series of results given in § 7 for air. 
We see that the rate of leak is greater in oxygen than in air ; 
no comparative figures need he given, as these would vary accord- 
ing to the voltage chosen. 
The leakage in hydrogen is less than that in air; in carbonic 
acid it is less for 4 volts, but greater for 90 volts, than it is in air ; 
for the latter voltage the leakage in carbonic acid is greater even 
VOL. XXL 2/7/97. 2 E 
