108 Hartiteyv—An Investigation of the Connexion between 
Quantity of Rubidium. 
Rubidiun. 
(1) 2:0 grs. in The spectrum is continuous and very intense. The banded 
5 portions. spectrum of fine lines is well shown between 5100 and 4400. 
(2) 1:0 gr. in 
2 [PORNO There is an indication of the bands described above in both 
(3) 0-5 pr. in these spectra. 
2 portions. 
(4) O'1 gr. No bands. The line-spectrum, as previously described, is 
strong. 
CASIUM. 
CsCl was the salt used. Photographed with Wratten and Wainwright’s 
panchromatic plates. 
Description of Spectrum. 
Quantity of 
Cesium. 
2 grs. A continuous spectrum without bands, but with many lines. 
Measurements of all the lines in the flame are compared with those 
of Ramage (Proc. Roy. Soc., 1902, vol. 70, p. 304). 
The line \ 6984 observed by Ramage does not appear. 
A 
Lines. a (Ramage). Intensity. 
7805:98 Rb. Impurity. 
7665°6 K. Impurity. 
A feeble pair. 7290 
7236 
A very strong broad line, 
degraded towards the 
red. 6973 6984 6 
: Be. eh . 6866 6974 9 
A fairly strong pair.* 16822 6869 ) 
Pair, very strong,* de- 6730 6829 2 
graded towards the red. 6712 6722 9 
Feeble. )A pair of (6630 6630 2 
Fairly strong. {fine lines. (6590 6590 8 
A pair of feeble fine (6472 6472 2 
lines. (6433 6433 2 
Fairly strong, degraded 6356 6354 8 
towards the red. 
Very faint, diffuse. 6334 
Very faint, diffuse. 6295 Rb. Impurity. 
* The fairly strong pair is represented by two faint lines in the spectrum photographed by Ramage ; 
and the pair, very strong, corresponds with only one line, the wave-length of which is the mean of the two. 
