49G 
MESSRS. W. DE LA RUE AND H. W. MULLER OR THE 
Tube 150. CO 3 . 
Battery insulated 8540 cells. 
The positive pole was connected to No. 1 ring ; the negative to No. 17 ring. The 
centre ring (No. 9) to earth, and each ring in succession connected with the electro¬ 
meter. Pressure about 0'5 millimetre". The deflection was positive between 1 and 9, 
and negative between 9 and 17. 
The diagram, fig. 19, shows the arrangement of the apparatus. The wire T, T', 
was connected at T' to each ring in succession from No. 1 to No. 17. 
Fig. 19. 
I. 
Eing. 
Potential. 
Distance from 9th ring. 
VI. 
Eatio of distances. 
Column T4. 
II. 
Divisions. 
III. 
Eatio. 
IV. 
In inches. 
V. 
Centims. 
1 
+ 114 
3-563 
15-975 
40-5 
4-096 
1-150 
2 
+ 93 
2-907 
14-075 
36-0 
3-608 
1-242 
3 
+ 79 
2-469 
11-925 
30-2 
3-058 
1-239 
4 
+ 66 
2-063 
10-050 
25-5 
2-577 
1-253 
5 
+ 53 
1-657 
7-950 
20-2 
2-038 
1-230 
6 
+ 42 
1-312 
5-900 
15-0 
1-513 
1-153 
7 
+ 32 
1-000 
3-900 
9-9 
1-000 
1-000 
8 
o-ooo 
2-000 
5-1 
9 
o-ooo 
o-ooo 
o-o 
o-ooo 
10 
o-ooo 
1-900 
4-8 
11 
- 42 
1-000 
3-850 
9-8 
1-000 
1 -boo 
12 
- 38 
0-905 
5-850 
14-9 
1-519 
1-679 
13 
- 59 
1-405 
7-950 
20-2 
2-065 
1-470 
14 
— 64 
1-524 
9-975 
25-3 
2-590 
1-700 
15 
- 78 
1-858 
11-975 
30-4 
3-111 
1-674 
16 
— 94 
2-239 
13-925 
35-3 
3-616 
1-615 
17 
-132 
3-144 
15-875 
40-3 
4-123 
1-312 
* The tube not being attached to the pump connected with the McLeod gauge, the pressure could not 
be exactly determined. 
