348 
THE FLAME-SPECTRUM OF LANTHANUM. 
Hartiey AND Ramace—Banded Flame-Spectra of Metals. 
The oxide was heated in the oxyhydrogen flame. Bands degraded towards 
Remarks. 
the red. 
eee Description. 
5710 Weakest. | if 
5682 Edges of component bands 
54 > degraded towards the < First Group. 
29 red. 
02 Strongest. | 
5517 Weakest. f 
oe | Edges of component bands 
3h > with no marked differ-< Second Group. 
09 | ences in intensity. 
5382 Strongest. L 
4463 Weakest. 
08 
53 
47 Edges of component bands ; 
42 easily distinguished, being : " 
37 well defined and degraded Third Group. 
32 towards the red. 
27 
22 
18 Strongest. 
43879 Edge of band on the next group or band, the components 
of which are not distinguishable if there are any. 
Band degraded towards the red. 
4371 Sharp and strong. 
Lines in Thalen’s 
spark spectrum. 
5656°5. 
5631-0 double. 
5602°0. 
5516°0. 
5485:0. 
5409:°0. 
5881°0. 
4462°5 Di. ? 
4457°5 Sm. 
4452:0 Sm. 
4446-0 Di. ? 
4430:0. 
4427-0. 
4418°5 Sm. 
4379°5 Sm. 
4370°1 Sm. 
There appears to have been lanthanum in the preparation of samarium 
examined by Thalén, or samarium in this specimen of lanthanum nitrate. 
There 
was also probably lanthanum in Thalén’s specimen of the didymium salt, from 
which the spark-spectrum was taken. 
The flame-spectrum was taken from a specimen of lanthanum ammonium 
nitrate, kindly given by Professor C. M. Thompson, D.Sc. of the University College 
of South Wales, Cardiff. It had been prepared by the method of Auer v. Welsbach, 
from monazite. 
It is to be remarked that Exner & Haschek give lines in the spark-spectrum 
of lanthanum, having wave-lengths which approximate to those of the edges of 
several bands in the third group of the flame-spectrum, viz. 4455:99, 4436-02, 
4433°15, 4423°37, 4419°30, 4378-24. 
