THE STRUCTURE OF THE SERIES OF LINE- AND BAND-SPECTRA. 561 
9. Strontium. 
1. SussipiaRy Series (3rd Component). 2. Supsipiary Series (1st Component). 
7 set : : ero SS aa cae =31077°7 
log >, = n— log 6, =5°10018, — 10 Ags 
(m+ p)| vobs. | v comp. a K-R. Ole 
P- ; (m+ )| — v obs. |v comp. Cam, K-R. 
35 20694°3 | 20694°3 O00) 4 07 
4:5 25374°7 | 253748} -O-1 - 26 2°9 14142°9 141429 | 00 | -—96- 
55 275544 | 275571) -2°7 | -11°7 3°9 225315 , 225301) +14 | + O1 
6°5 287580 | 287606); -26 | — 95 4-9 25868°7 | 25868°7 00 | - 22 
75 294980 | 29497°5| +05 | + 3-1 59 27559°0 | 275565; +25 | -— Ol 
85 29987-9* | 29982-4) +55 | +16°3 6°9 28533°3 | 28533°3 - 0:0%| = 2:2 
The enormous discrepancies in the first lines of the 2nd subsidiary series shown 
by Professor Kayser’s formula might, as in similar cases before, be considerably reduced 
by employing these lines in the computation of the constants. But this would involve 
inadmissible residuals in the shorter wave-lengths. It may be shown by easy calcula- 
tions that no numerical form of KaysEr’s equation can represent the observed wave- 
frequencies with the same accuracy as the Rypperc-THiELe formula. After the 
foregoing discussion of the relative merits of the two formule I need not dwell upon 
this point any longer. The shortest wave-length of the 1st series of calcium is badly 
represented by both equations ; and although Kaysgr’s formula is distinctly better than 
ours, neither formula is satisfactory. It is worthy of note that there are two other 
instances, viz. the first series of Aluminium and the second series of Thallium, where 
both equations distinctly fail. 
10. Zinc. 
1. Sussiprary SzriEzs (1st Component), 2. SUBSIDIARY SERIES. 
log a, = 494561 — 10 log a, =4°93860 — 10 
«o = 429186 . «o = 42924: 
log b, = 4°43373, — 10 i log b, = 4'84137,, — 10 ‘ 
Obs. — Obs. — 
(m+ )|  v obs. COMPS | Comp, K-R. (m+ )| — v obs. v comp. Cane. K-R. | 
30 29889°3 | 29889:2} +0:1 +0°7 9°45 20787:0 | 20787:0 0:0 | —251- | 
4:0 35701°7 | 35701°6} +01 -0°3 3°45 32550°0 | 32550°5} —-—0°5 0:0 
5:0 38333°3 | 38332°0} +1°3 -0:9 4°45 36864:0 | 368631 +09 | -— 02 
6:0 39745°5 | 39745-5 0-0 +1:8 5:45 38940°0 | 38939°2} +08 | + 0-2 
7-0 40592°7 | 40592:7 0:0 +6°5 6:45 40101:0 | 40101°5| -05 | + 06 
80 411400 | 41140°6} -0-°6 ae T:45 40820:0 | 408184) +16 | + 3:3 
* The line observed is the first component : v=29408°0. 
