Chemistry and Physics. 401 
in ytterbia, and B in yttria. After pushing the treatment as far 
as possible with the amount of material in hand, he submitted the 
five fractions to Thalén, who found bands common to all the frac- 
tions and hence due probably to erbia. These had the following 
wavelengths: 6660-6680 (weak), 6515-6545 (strong), 6475- 
6515 (quite strong), 5400-5415 (quite strong), 5225-5235 (very 
strong), 5185-5225 (strong), 4865-4877 (strong), 4475-4515 
(quite strong). The following bands varied markedly from one 
fraction to another: 
Fraction A. Erbium ? Fraction B. 
Extr. from Extr. from Mean Extr. from Extr. from 
Wave-length. ytterbia residues. erbia 126-7. fractions 126-7. erbia 126-7. phot og 
quite 
strong 
y 6400-6425 Teor trace weak weak 
x 6480 strong fails fails fails 
, fails or quite 
F 
5360 fails Hea trace feeble strong 
are rich in yttria minerals. —C. R., lxxxix, 478, Sept., 1879. 
G. F. B 
5. Notes on the two new Elements announced by Cléve.—Soret 
has called attention to the fact that he pointed out in the spring of 
1878, the two bands which characterize holmium, as not belonging 
to erbia, but to a new earth which he called provisionally X an 
which is perhaps identical with philippium since discovered by 
Delafontaine, side these two eee 23 Soret recognized. three 
other absorption bands; one less refrangible than A, a second 
overlapping the band of erbia in the indigo, and a third, faint, in 
the violet a little beyond A. In the ultra violet-spectrum six 
absorption-maxima exist from H to R. In samarskite, the earth 
Xis, relatively to erbia much more abundant than in gadolinite. 
As to the red ray which characterizes thulium, Soret had already 
observed that also in some ytterbia products which had been sent 
to him for examination by Marignac. Lxecog DE BotsBavDRAN 
confirms Soret’s statement in regard to the red thulium ray, hav- 
