216 
PROFESSORS G. D. LIVEING AND J. DEWAR ON 
on the more refrangible side of the strong blue line, and gives to it all the appearance 
of a reversal with an expansion of the bright wings unequally extended on the two 
sides. As the strong blue line is, however, often really reversed, the effect is then 
that of a double reversal, that is to say, the appearance is that of a broad bright 
band with a narrower dark band within it and a bright line in the middle of the 
dark band. The second line rather quickly dies out as the lithium evaporates, 
leaving the strong blue line comparatively permanent. We have never observed any 
such second line, or companion, to any of the other lines of lithium. The new series 
begins with a line at wavedength about 3232, and dies out with a very diffuse line at 
about wave-length 2359. The following is a list of the ultra-violet lines we have 
observed. 
Approximate 
wave-length. 
Remarks. 
Approximate 
wave-length. 
Remarks. 
3984-5 
2561-5 
Reversed. 
3913-5 
Diffuse. 
2475-0 
3862-3 
f Somewhat obscured by the 
2425-5 
3799-0 
[_ cyanogen bands in this region. 
2394-5 
Diffuse. 
32320 
2373-5 
Very diffuse. 
2741-0 
Reversed. 
2359-0 
Very diffuse and weak. 
Barium. 
The barium lines are numerous, but do not fall into easily recognised harmonic 
series. 
Barium lines. 
Approximate 
wave-length. 
Remarks. 
Approximate 
wave-length. 
Remarks. 
3991-8 
3320-9 
3908-5 
3279-8 
3891-0 
3261-0 
3793-5 
3070-3 
3660-7 
2785-1 
3598-7 
2771-0 
3592-8 
2739-0 
3579-1 
2702-0 
3544-0 
2647-0 
3524-5 
2634"5 
3499-2 
Very strong, reversed. 
2596-7 
3419-3 
2542-7 
3375-6 
2347-0 
Sti-ong. 
3354-8 
2335-0 
Very strong. 
3347-7 
| 
2304-5 
Strong. 
