446 
DR. W. M. HICKS: A CRITICAL STUDY OF SPECTRAL SERIES. 
m. 
F. 
dX. 
27831-95. 
F. 
10 <1 
(5) 26885-78 
- -29 
34-10 
(1) 28782-42 
148-23 
(1) 28930-65 
Notes .—Displacements are in evidence except for Fi. A desired wavedength can be obtained very 
closely since a 8i displacement produces a change of only • 42. Consequently in deductions by displace¬ 
ment the results have little weight, and in fact would have none at all were it not that we now know as a 
fact that such exist. Failing such likely displacements, recourse has been had in a few cases to linked 
lines and here their evidence has weight. 
m = 2. For Fi, ( - 16S) (1) 42192-13 = 18-21; (9S) (1) 42233-12 = 18-45; mean taken. For F 2 
(-58) (1) 42326-07 = 34-22. 
m = 3. There is no observed Fi, but (3) 19351-20.e = 20070-91 or with E.V. 71-65; 
Fi (3) ( 7 A 2 ) = 20103-85 and 20105-52 is observed by E.V. dX = - - 42. 
For F 2 , (-388i) (4) 20174-83 (E.V.) = 90-22; (208i) ( 2 ) 20198-39 = 90-29 mean taken. 
For Fi, (-58) ( 1 ) 35580-73 = 88 - 88 , also F 2 , (-58) ( 1 ) 35695-03 E.V. ±2 = 703-18 ± 2 . 
m = 4. The observed line for Fi is much stronger than should be expected; also its 0-C is in the 
opposite direction to that of the others. It may be displaced by on the sequent and so intensified. 
The A 2 would produce 0-C = -00 and the observed = Fi (4) (Ao), or it may hide the real Fi. Fj 
is inserted as 32819- 150-50. It only indicates that 32819 is the correct value of F'. F 2 is given as 
(58) (1) 32793-11. 
m = 5. Fi shows a link e = 719-81 to (3) 25241-75. F 2 is entered as (188) (4) 24665-59 = 37-25, 
but has no weight. Fj = (15|8) ( 1 ) 31279-10. 
m = 6 . F 2 is the mean of ( - 6 S 1 ) ( 2 ) 25536-15 = 45-87 and (78) ( 1 ) 25557-12 = 45-78. The 
calculated value of Fi gives a better 151-7 to F'l. 
m = 7. The calculated Fi is 26009-30. The deduced value is ( 1 ) 25290-92.e = 26010-73, which again 
has an apparent approximate e link = 720-77 forward to an E.V. line at (2) 26731-40. This is 
however a coincidence as the last line is 82 ( 2 ). In connection with the linked line 26010-73 maybe 
taken the pair of lines (- 68 ) (3) 26001-11 = 10-89 and (7^8) (3) 26022-85 = 10-63 whose mean agrees 
precisely with the former. For F 2 a similar split with two may be observed ( - 2 ^ 8 ) (3) 26123 - 03 = 27-07 
and (28) (1) 26130-61 = 27*30. 
m = 8 . F 2 is (5) 25796-57.C; also ( - 28) ( 2 ) 26512-75 = 16-05. It may be noticed that the separa- 
tions to Fi and F' are both about 2-3 too small, or 1^8 on the limit. Fi is ( 2 ) 28540-26.6 and F 2 is 
( 1 ) 28659-08.e. These linked lines in this order are therefore reliable. 
m = 9. F 2 is (1) 28389-59.6. 
It should especially be noted how with increasing order the normal calculated lines 
appear as observed with good intensities. As in the other instances it suggests itself 
that this is due to the diffusion of the energy of the lower order lines into the 
formation of numerous displaced ones. The usual accurate determination of the limit 
as the value of (Fi + Fj) is not here applicable as, for the reason given above, the 
determination of the actual displaced lines is unreliable. These values are printed in 
italics. The more reliable results point to a limit higher than that calculated in 
S ( 00 ), with ^ about + 2. 
