on the spark spectra of titanium, chromium and manganese. 63 
The line 2866'8 appeared to be divided into eight constituents ; 
there were two stronger ones vibrating parallel, and six weaker 
ones perpendicular, to the lines of force, but the constituents 
were seen clear only by separating them by the calcite prism. 
The following gives the values of the measurements between 
corresponding constituents. 
X 
d\/\ 2 
+ 3-16 s 
+ 2-03 s 
+ 1-65 p 
+ 0-92 s 
The measurements were taken between corresponding con- 
stituents. The two constituents vibrating parallel to the 
lines of force were much stronger than those vibrating per- 
pendicular ; but they themselves were equally strong. Of the 
2866-80 
0 
- 0-92 s 
- 1-65 p 
-2-03 s 
-3-16 s 
six constituents vibrating perpendicular, the middle one of 
each group of three was stronger than the other two ; but 
both groups of three were the same in intensity and dift'use- 
ness. There appears to be a simple numerical relationship 
between the eight constituents. 
The following lines were divided into six constituents which 
were seen clearly separate only by use of the calcite. The 
measurements were taken between corresponding constituents. 
3147-23 
2855-73 
2757-75 
+ 2-32 s 
+ 1-62 s 
+ 0-75 p 
0 
-0-75p 
- 1-62 s 
- 2-32 s 
+ 2-14 s 
+ 0-85 s 
+ 0-64/) 
0 
- 0-64 p 
- 0 - 85 s 
-2-14 s 
+ 2-11 s 
+ 0-85 s 
+ 0-67 p 
0 
-0-67 p 
-0-85 s 
-211 s 
The two constituents vibrating parallel were sharper and 
stronger than the others, and the two extreme outside ones 
were very weak. They appear to be simple multiples of one 
another. 
I The two constituents vibrating parallel were broad and strong, 
r and not easily separated ; whilst the two extreme outside 
ones vibrating perpendicular were very weak and impinge 
upon the adjoining ones. 
do. 
The line 286T01 was divided into five constituents, and the 
measurements were taken from the centre of the middle one. 
2861-01 
+ 3-30 s 
+ 1-70 p 
0 8 
-1-71 p 
- 3-31 s 
I Tire three middle constituents were stronger than the two out- 
side ones, and the innermost was slightly stronger than the 
other two ; the two extreme ones were very weak and almost 
impinged upon the outer edges of the two vibrating parallel 
to the lines of force. There appears to be a simple numeri- 
\ cal relation between them. 
