on the spark spectra of titanium, chromium and manganese. 83 
The following lines were divided into two. They were all 
very diffuse, and it was impossible to distinguish if there was 
any further separation. 
X 
dX/\ 2 
4059-0 
+ 1-44 
0 
-1-44 
3569-8 
+ 1-14 
0 
-1-14 
3460-2 
The separation was very narrow, and it may be an ordinary 
reversal. 
2638-1 
+ 1-34 
0 
-1-34 
General results of chromium and manganese. 
The more important results of the preceding observations 
of the lines of chromium are : — 
(1) The division of 2866'80 into eight constituents and a 
simple numerical relationship between them. The line 314723 
divided into six and the line 2861'0 into five; the constituents of 
each of which are also numerically related in a simple way. 
(2) Several lines which may be grouped together in having 
a similar appearance and polarisation and identical values of d\/\ 2 
for their constituents. Examples are the lines 2855'7 and 2757 75 
which are divided into six, and the lines 342292 and 335864 
which are divided into four. Also there are several lines amongst 
those divided into four whose values for dX/X 2 of their constituents 
are again simply numerically related. 
(3) Amongst the lines which are divided into three, there 
are some which can be compared with each other in a similar 
way. And also the values of dX/X 2 for the constituents of some 
lines are simple multiples of the values of those of other lines. 
(4) The various lines show various types in the appearance 
of their constituents. As regards the triplets the general appear- 
ance is that the middle constituent is at least twice as strong as 
either of the two outside ones ; but there are some exceptions 
The middle constituents of several of the triplets are only a shade 
6—2 
