186 
Mr Almy, On a Diminution of the Potential Difference, etc. 
Table III. Potential difference in tube. 
Gas pressure 
Without 
magnet 
Magnet nor- 
mal to tube 
Magnet paral- 
lel to tube 
0*28 
3200 
2600 
2750 
0*15 
3600 
3000 
3100 
0*10 
4000 
3250 
3350 
0-06 
4800 
4000 
4100 
0-04 
5400 
4500 
4700 
0-03 
5800 
4800 
5000 
0-02 
6800 
5500 
5800 
0-016 
8400 
6100 
0-010 
28000 
7500 
0-007 
34000 
9600 
Table IY. 
Cathode 
Area 
Without 
0-12 
0-28 
0-78 
1-13 
1-77 
2-54 
314 
3-80 
5-30 
magnet, 
Spark Gap 
1-93 
2-01 
2-27 
2-36 
2-6 
5-55 
9-00 
12-4 
14-1 
Poten.-Diff. 
27 
28 
28 
31 
33 
63 
96 
110 
132 
With 
magnet, 
Spark Gap 
1-90 
1-93 
2-01 
2-06 
2-14 
2-27 
2-40 
3-00 
4-10 
PoteD.-Diff. 
27 
27 
27-5 
28-5 
29-2 
30 
30-3 
31-5 
48 
