Mr Richardson , On an attempt to detect radiation , etc. 177 
Pressure 
Initial 
Headings of 
Electroscope 
Final 
Readings 
Leak in 
Scale 
Divi- 
sions 
Duration 
of Experi- 
ment 
Leak 
per hour 
mm. 
1-81 
Left Right 
30-2—37-2 
Left Right 
30-2—36-4 
0-8 
44 mins. 
1-0 Div. 
Wire not 
excited 
1-81 
30-2—36-4 
30-2—36-0 
0-4 
36 „ 
0-7 „ 
Current, 
passing 
tb rough 
wire 
•36— *28 
300—38-0 
29-8—36-0 
1-8 
3 hrs. 
0-6 „ 
1 
No current 
through 
wire 
•28— -37 
31-0—39-2 
31-0—37-2 
2-0 
3 „ 
0-7 „ 
Current 
through 
wire 
The above experiments had been made with the cylinder 
charged positively; they were now repeated with a negative charge 
but no leak was obtained. The small Leyden jars (of about 
400 cms. capacity) were next replaced by a paraffin condenser 
whose capacity was about half a centimetre, and the pressure was 
varied down to 001 mm. With these alterations several observa- 
tions were taken, of which the following are examples. 
1. Aluminium wire , -6 mm. thick. 
Time of 
Experi- 
ment 
Pressure 
Diverg< 
lea 
Initial 
mce of 
ves 
Final 
Leak 
Rate 
of 
Leak 
mins. 
50 
mm. 
• 5— -08 
13-4 
12-4 
Divns. 
1-4 
per hr. 
1-5 
No discharge through 
O O 
wire 
50 
• 08— -3 
12-4 
11-4 
1-0 
1-1 
Current through wire 
2 . Steel 
wire , •( 
39 mm. 
thick a\ 
i very l 
ow pressures. 
100 
© 
r 
6 
1 
41-5 
40-2 
1-3 
0-8 
No current through 
wire 
106 
• 03— -07 
43-2 
I 42-2 
1-0 
0-65 
Current through wire j 
