68 
MESSRS. W. DE LA RUE AND H. TV. MULLER ON THE 
The following observations were made when the straight wire w r as made positive; 
when the contact-key (figs. 2 and 3, Part I., page 59) was in the position fig. 2, this was 
effected. It was noticed that when in this position the current of the battery itself, 
when short-circuited, was less than wdien the key was reversed as for the first series, 
■when the ring was positive, the contact being more perfect in one or other case. 
July 4th.—11,000 cells, short-circuit, deflection 54', total battery-resistance 
= 302,100 ohms. 
* 
Pressure. 
Deflection with 
tube. 
Total resistance. 
Tube-resistance. 
Tube-potential 
V. 
m.m. 
M. 
ring - 
oil ms. 
ohms. 
cells. 
18-7 
24,605 
17'0 
1,358,000 
1,055,900 
8531 
17-8 
23,421 
15'0 
1.550,000 
1,247,900 
8837 
16-0 
21,053 
29-0 
749,200 
447,100 
6564 
11,000 cells, short-circuit, deflection 50°, total battery-resistance = 348,500 ohms. 
Pressure. 
Deflection with 
tube. 
Total resistance. 
T ube-resistance. 
Tube-potential 
V. 
m.m. 
M. 
ring - 
ohms. 
ohms. 
cells. 
13-5 
17,763 
24-0 
932,600 
584,100 
6890 
12-1 
15,921 
25-0 
890,900 
542,100 
6695 
107 
14,079 
29-0 
749,200 
400,700 
5884 
9-0 
11,842 
31-0 
691,100 
342,600 
5453 
7-9 
10,395 
34-0 
615,800 
267,300 
4775 
6-8 
8947 
37-0 
556,200 
207,700 
4109 
5-3 
6974 
42-0 
461,500 
113,000 
2694 
4-6 
6053 
42-0 
461,500 
113,000 
2694 
11,000 cells, short-circuit, deflection 51°, total battery-resistance = 336,200 ohms. 
Pressure. 
Deflection with 
tube. 
Total resistance. 
Tube-resistance. 
Tube-potential 
V. 
m.m. 
M. 
ring - 
ohms. 
ohms. 
cells. 
4-3 
5658 
41-0 
478,000 
141,800 
3062 
3-8 
5000 
42-0 
461,500 
125,300 
2986 
3-410 
4487 
43-0 
445,300 
109,100 
2695 
2-789 
3670 
46-0 
400,300 
64,100 
1762 
2-488 
3273 
45-0 
415,000 
78,800 
2088 
2-327 
3062 
46-0 
400,300 
64,100 
1762 
1-966 
2587 
45-0 
415,000 
78,800 
2088 
1-745 
2296 
50-0 
348,500 
12,300 
388 
