305 
In the table the most violet component is marked by —, the most 
red by +. In this case the splitting up is not = 2d, as is given 
in the heading of the column, but = dà; 0 does not mean that the 
line is at the place of the original unsplit one, but only that there 
is a component there. 
5. General results. When we compare the results in what 
precedes, it strikes us at once that though the general course of 
the results may be the same, there yet occur a good many devia- 
tions, which amount to more than the given probable error. Further 
it occurs occasionally that a quadruplet is mistaken for a triplet, 
which is not astonishing with the middle components of these often 
blurred lines, which are so very close together. That something 
similar may be the case with other lines which are given as triplet, 
is not impossible. 
An agreement as Purvis gives between the quadruplets Pb 3740, 
Pb 2873, Sb 3723, Sb 3638, and possibly Sb 2668, Bi 2989, does 
not exist according to my measurements, except perhaps that between 
Sb 3638 and Bi 2989. When we examine whether there is perhaps 
some connection between the resolutions of the lines for which 
Kayser and Runee ') find the known constant differences of frequency, 
it appears that there is no such connection. VAN LOHUIzEN *) has given 
series in the spectra of tin and antimony. The correctness of this is, 
however, doubted by SAunNpers *) and ArNoups *). | have now examined 
whether the laws of Preston were valid for these series. Of series 
I, which v. Lonuizen gives for the tin spectrum, I have found the 
resolutions (i.e. the values for dé: 47H, see table) 29,6 and 56,1 for 
the lines 3656 and 2785; in this series 2408 has a resolution smaller 
than 59. In series VII I find for the lines 3801, 2851, 2594, 
2483, 2422 successively the splittings up 40,5, 42,5, 44,7 (56 and 
46,8), 45,9. In this 2483 gives a quadruplet, the other lines give 
triplets. Series VII]: 3175 and 2483 give successively 69,7 (56 and 
46,8) as splitting up. Antimony. Series XIII: the lines 3268 and 2574 
have successively a resolution of 40,9 and 45. Series XIV: 3505 
has the splitting up 63,7 and 2719 has 51.5. Series XX: 3233, 2653, 
2478 have the resolutions 60,0, 63, 68,7. 
. Ay ED: KAYSER und ©. Ruree. Ueber die Spectra von Zinn, Blei, Arsen, Antimon, 
Wismuth. Abhandl. Berl. Akad. 1893; Wied. Ann., 52, 93, 1894. 
2) T. van Lonuizen. Bijdrage tot de kennis van lijnenspectra. Diss., Amsterdam, 
1912. 
5) F. A. SAUNDERS. Astrophys. J., 36, 409. 
4) R. ARNOLDS. Das Bogen- und Funkenspectrum von Zinn (von A 7800—4 2069). 
Zs. f. wiss. Phot., 18, 325. 
