41 
while there have been found two indications of series of translation 
in the region of SCHUMANN viz. 
XXII and EE IE : 
XXII Asymptote = 53402.61 54744.87 
eS 2528.60 (Int. 20) 2445.59 (Int. 2) 
r=2 2159.32 2098.47 
r=3 2042.40 (o.r.o.) | 1987.30 (o.r.0.) 
The found series in the Antimony is indicated on the annexed 
plate, coloured in groups, just as that of the Tin. 
The first group of translation series is coloured black, the second 
group red, the last mentioned group blue. The succession of the 
black one is: XI, X, XII; that of the red one XIV, XIII, XV, XVI 
etc.; that of the blue one XX, XXI, XXII and XXIII. 
So it appears from this investigation that in the spectra of Tin 
and Antimony the series have been considerably shifted towards the 
side of the small wave-lengths, and so that they lie for the greater 
part in the ScHUMANN region. At the same time it has appeared from 
it that the intensity of the lines of one and the same series greatly 
decreases, so that only a limited number of lines has been observed. 
But though the number of lines is limited, yet the mutual relation 
that exists between the different members of one translation group, 
sufficiently proves the existence of series in the same form’) as we 
meet with them for other elements. ‘Though the series there are at 
once far more pronounced, yet the translation series exists there too, 
as I shall sbow more at length in my thesis for the doctorate. 
How we must distinguish the series found as principal and subor- 
dinate series ete. cannot be decided for the present. Not until a 
sufficient number of magnetic splittings up have become known in 
the ultra-violet spectrum of these metals, this investigation can be 
undertaken. The few things that are known about the Zeeman-effect 
of Sn and Sb, have been found by Purvis?). We will summarize 
it here. 
Purvis has measured the magnetic splitting up of the following 
lines in our tables. 
1) RypBERG’s statement, therefore (Rapports Paris 1900. T.II. p. 220) that Sn, Sb 
and some other elements present spectra built according to other laws, cannot 
be maintained. 
*) Purvis Untersuchungen über die ZEEMAN-Phänomene. Physikal. Zeitschr. 
p. 594. 1907. and the literature mentioned there. 
