252 
DE. T. R, MERTON AND PROF. J. W. NICHOLSON ON 
It is, therefore, a general fact that, without exception, the energy in the bulb 
spectrum has been transferred towards the members of higher term number iu all the 
component series—provided, as later investigation shows, that the effect is not due to 
a mere change in the energy distribution within the lines. 
The Helium Spectrum from the Capillary with a Condensed Discharge .—- 
On Plate 3 is shown the wedge photograph of the Helium spectrum from the 
capillary produced by means of a powerful condensed discharge with a spark-gap in 
the circuit, and for comparison, the ordinary spectrum developed on the same plate. 
The quantitative analysis follows the same method as in the last section, and the 
results for one plate are exhibited in the table below. On this particular enlargement 
the full length of the wedge was 35 mm. 
A. 
I) . 
A 
Helium ordinary). 
Helium (condensed discharge). 
Ratio 
cond./ord. 
K 
W H - 
Photo¬ 
graphic 
intensity. 
K 
W H - 
Photo¬ 
graphic 
intensity. 
7065 
3 ■ 95 
37 
0-418 
2 -62 • 
6678 
4-1 
12-3 
1-441 
27-61 
13-8 
1-617 
41-4 
1-50 
5876 
4-5 
18-2 
2 • 340 
219 
18-2 
2 • 340 
219 
1-00 
5047 
5-0 
— 
— 
— 
— 
— 
— 
— 
5015 
5-0 
11-5 
1 • 643 
44-0 
io-o 
1-428 
26-8 
0-596 
4922 
5-15 
7-0 
1 • 030 
10-7 
7-9 
1-162 
14-5 
1 ■ 355 
4713 
5 • 45 
10-2 
1 • 588 
38-7 
10-7 
1-666 
46-3 
1-20 
4472 
5-9 
15*7 
2-647 
444 
15-7 
2-647 
444 
1-00 
4438 
6-0 
— 
— 
— 
1-8 
0 - 309 
2-04 
4388 
6-13 
5-1 
0 • 893 
7-82 
7-7 
1 • 343 
22-0 
2-82 
4144 
6-9 
— 
— 
— 
1-5 
0-296 
1-98 
— 
4121 
6-95 
2-5 
0-496 
3 13 
4-0 
0-794 
6-22 
1-99 
4026 
7-4 
6-0 
1-269 
18-6 
6-0 
1-269 
18-6 
1-00 
3965 
7-7 
3-5 
0-770 
5-89 
3-9 
0 • 858 
7-21 
1 • 225 
3888 
8-0 
9-1 
2-080 
120 
8-5 
1-943 
.87-7 
0-729 
The most significant feature of these results is the fact that the central intensities 
for the three lines of the Diffuse series of Helium are the same on both photographs. 
When their heights were found to be the same in both cases, they were re-examined, 
and no difference can be detected. The fact that their “absolute’ heights were 
identical was of course accidental. At the same time the shapes of the lines are quite 
different (Plate 3), for A4472 is very much broader, and therefore contains, for the 
same height, very much more energy. The same applies to A4026, and to a less 
-extent to A5876, but the increase in A5876 is not comparable with that in A4472 or 
even X4026. We are in the presence of the same phenomenon as before, but with the 
difference, that whereas in the bulb the transfer to higher members of the series takes 
the form of increased central intensity but not increase of breadth, with the con¬ 
densed discharge the extra energy goes into the form of increased breadth. 
