390 
DE. W. M. HICKS: A CRITICAL STUDY OF SPECTRAL SERIES. 
here but (l) 36493‘82 is less by 5, i.e. = ((^\) F(l). We can arrange lines to go with 
it as a satellite set, viz., 
[36498-90] 
25-45 
(3) 36473-45 
1864-50 
1863-64 
[38363-40] 
17-64 
(2) 38345-76 
26-31 
(1) 38337-09 
830 (1) 39193-40 
17-66 
829-98 (2) 39175-74 
Hei •e we bud the same Odj for Fj and F,, whilst in F we had it only for Fj. The 
set with separation 17 show no Fj, and again is numerically an exact oun multiple 
displacement, viz., ^ which gives 17-0. The line found close to the expected—(<^i) F^ 
above—forms part of a chain 
(1) 32765-29 1864-47 (3) 34629-76 1864-06 (l) 36493-82 
It may be the representative corresponding to the satellite displacement observed 
in F for m = 2, 3. 
Using links 2e + w = 18761-38 and 2e-\-v = 19056-2 w^e should find lines at 39678-79 
and 39383-97 with the corresponding lines to Fg, Fg beyond the observed region. As a 
fact, we find lines at (3w) 39683-95 and (1) 39386-98. The first corresponding to a 
— displacement should give 2c.v.Fi(l) = 39679-70. The second would differ from 
the same displacement l)y 3 and is therefore inadmissible. It should be noticed that 
])oth the 3c and 2e + «, sounders give lines larger by unity than the expected value. 
This may, of course, be due to coml)ined errors in the sounders and observation errors, 
but the F are entered in the list as if the sounders are correct. As none of the 
F (1) or F (1) lines can be observed, their means can have no weight for an accurate 
determination of the limit. 
m= 2. The F lines are in the ultra-violet, and should be, with the limit chosen, at 42842'73, 
44707-23. With sounder e-fw = 11742-10 we find the set (4) 31102-16 1863-17 (<1) 32965-33 
with a small separation corresponding to that for F^. It gives Fj = 42844-26 and Fo = 44707-43. 
But the set appears to be really Fj (16), F^ (16). 
m = 3. A displacement 3^ in F 2 ( 00 ) produces 5-42. The F 2 line is not observed but (2) 39404 is 
practically an exact ( - 3^) F 3 . In further illustration of this we find (2) 37431 -03 linked to it by -d and 
5 - 6 I (ie. another 3j) ahead in tbe remainder of the triplet (1)37436-64 828-13 (In) 38264 - 77. The 
lines in question are ( - 8^) F^ ; (7.( - 28^) Fj ; d.{ - 28^) Fg. 
rn = 4. F 3 is (1) 32362-98- « = 28229-80 which, as referred to above, is also (1) 26257-20-1- 1972-60 
close to d link. For Fg, (-8,) (4) 29053 - 89 = 29059 - 54 or (28^ (Ia) 29071-03 = 29059-73 or 
(3cd (1) 29076-10 = 29059-15. Take the mean 29059-47 as Fg. Several other lines in this neighbour¬ 
hood show indications of displacement by multiples of 8 j, i.e. that the energy proper to Fg has gone 
into a number of collaterals. None of the direct F are observed but there appears a parallel set displaced 
3, viz., (1) 35064-09 1864 34 (1) 36928-45 with (1) 37742-12 due to a further 33j displacement. 
The F lines are entered as due to these. 
