EEV. T. E. EOBINSON ON SPECTEA OE ELECTEIC LIGHT. 
977 
Table XXII. (continued). 
No. 
Place. 
Diff. 
C.P. 
E. 
* 
73. 
Sl 22-99 
r-M9 1 
1 +1-51 J 
33 
1 
23 
0 
None in H, C.P. ; four in H, R. 
74. 
34 25-56 
r-1-36 1 
1 +0-94 / 
55 
9 
22 
0 
Frequent in N and 0. 
75. 
34 27-45 
r -0-95 \ 
1 +0-75 ] 
38 
13 
37 
2 
Only one metal wanting in N, E. 
76 5. 
34 30-09 
/ -0-92 ] 
1 + 2-01 r 
63 
20 
18 
0 
N, C.P. with all. 
77. 
34 33-43 
r-1-63 1 
1 +1-27 ; 
51 
1 
38 
1 
The two *s are Al, 0 ; Te, N. 
78 
34 35-83 
r -0-83 1 
1+1-67 ; 
53 
1 
19 
0 
AE with Pb, C.P. ; the * is Ca, H. 
79. 
34 39-03 
r-1-53 1 
1 +1-27 1 
43 
0 
19 
0 
None in H, C.P. These far-violet are ill defined and hard to bisect. 
80. 
34 41-85 
r -1-85 1 
1 +1-85 1 
42 
0 
28 
0 
Few in H and A. 
81. 
34 44-80 
r -1-85 1 
1 +1-85 f 
51 
0 
12 
0 
With Co, C.P., in all the gases. 
82. 
34 47-73 
142 
0 
13 
0 
Most frequent in CO. 
83. 
34 51-35 
{ +1-45 } 
30 
0 
14 
0 
0 has only Zn in C.P. and Mg in E. 
84. 
34 55-81 
f -2-31 1 
1+1-89 ; 
15 
0 
6 
0 
None in 0, C.P. 
85. 
34 59-34 
1 -2-24 j 
1+1-66 ] 
10 
0 
8 
0 
Among the most notable of these are, — 
No. 3 a. It is one of the three brilliant bands in H, C.P., and is more intense in that 
gas than in any other. Its mean from 22 of H, C.P., is 32° 38'‘52, almost identical with 
the general mean. It is also extremely intense in other gases, e. g. A, with silver and 
u’on ; at other times dull or even faint. In H it is generally separated by a dark space 
from the rest of the spectrum, as if the other red rays were condensed into it. It seems 
to have a fine line preceding it, which in many cases is separated enough to be bisected. 
In E. it is of much less importance ; its place is that of Feaunhofer’s C. 
No. 12 is remarkable for its much greater display in E. than in C.P. ; the same occurs, 
though in a less degree, in Nos. 18, 24, and 64. 
No. 15 y. This beautiful band is nearly, but not exactly, in the place of D, and like 
it is double, though my glass prisms often fail to divide it fairly. With the two prisms of 
S*C the components are generally equal, but I think further apart than those of D with 
the same prisms. In K, A, they are seen separate as intense *s; in CO the second is 
often the brightest. In O it is often dull and sometimes wanting (and the same^may 
he said of the orange and yellow lines generally). 
No. 16 coincides with the yellow band of sodium. In the A spectrum of this metal. 
No. 15 7 is only nb ; in N it is a #, but No. 16 is far more brilliant ; it retains its bright- 
ness during exhaustion and with the spark discharge. It is exactly in the place of D. 
Nos. 18 and 19 are intense orange *s in mercury vapour with electrodes of mercury. 
No. 22 S is another beautiful band of common occurrence. In C.P. five metals have 
. it in all the gases ; A and N have it with all the metals, though of very unequal bright- 
ness; O with 11, H with 12, and CO -with 19. It seems to be connected with No. 21,, 
