DR. W. M. HICKS: A CRITICAL STUDY OF SPECTRAL SERIES. 
399 
between the calculated values and those found hy sounding is remarkably close. The 
only doubtful case may be that for m = 1. If 20559 be taken for this the formula is 
only slightly changed and the agreement almost as good, the calculated value for 
m = 3 giving 0 —C d\ = ’05 instead of ‘00. It is excluded because it cannot belong to 
a diffuse series in which the limit is S (oo). 
Table of Parallel XD Series. 
After m = 2 the wave-numbers at the head of each set are those calculated from 
the formula and are not, as usual, enclosed in [ ]. The links are entered as attached 
to the respective observed lines. On the right of each is entered the O — C(dX) 
calculated as if the error were on the observed line. They would be less—often 
considerably less if calculated on the series line itself. 
m. 
(2Si)D(oo). 
D(^). 
( - 28i) D ( cc). 
1 
[20.5.50-58], = (- 281 ) 
31-06 
(1) 20581-64 
31-06 
[20610-70], =( + 28i) 
e.( 2 ) 27864-16 
-06 
6 .( 6 ) 27926-53 
-22 
m.( 6 ) 24683-37 
-06 
77.(<1) 24749-35(-Si) 
-11 
y.(2) 24977-40 
-18 
®.(5) 25036-99 
-26 
0 
(2) 38345-76* 
20-60 
(10) 38366-36 
21-20 
[38.387-61] 
(1) 31033-15 ( 8 i).e 
-02 
(<1) 34251-50.77 
-02 
(5) 33915-20 (-28i).r 
-00 
(2) 33062 - 4 . 3 .® 
-02 
or 
®.(5) .35499-89.6 
-12 
[38345-11] 
21-25 
(26940-63).6.77 
-05 
(<1) 34212-13.W 
-01 
or [38390-24] = (28i) 
(4) 33908-99 ( 681 ).® 
-09 
(<1) 31076-51.6 
-07 
3 
44004-50 = -81 
21-94 
44026-48 
21-76 
44048-20 
(<1) 36690-52.e 
-01 
(1) 36712-34.6 
0 
77.(1) 40867-04.6 
•01 
(1) 32262-65.6.® 
-02 
(2) 39598-95.® 
- -02 
(2) 32304-23 (-28i).e.® 
•03 
4 
46557-99 
20-24 
46578-23 
21-43 
46599-66 
(.3) .34815-79.6.® 
-00 
[39264-13.6] 
(1) 31971-46.26 
•00 
(<1) 34836-78.6.® 
- -05 
(1) 27836-93.26.77 
•17 
(35130-95).6.?a 
0 
5 
47927-39 
21-39 
47948-78 
21-45 
47970-23 
(<1) 28871-19.26.® 
-00 
(<1) 33.322-45.26 
- -18 
(2) 36523-41.6.77 
•03 
(3) 33301-47.26? 
-20 
(3) 36209-04.6.® 
- -24 
(3) 36229-78.6.® 
•1.3 
(1) 29189-92.2e.M 
- -29 
6 
48748-78 
21-35 
48770-13 
21-35 
48791-48 
(1) 37.300-91.e.« 
-04 
(<1) 34140-88.26 
-09 
(4) 34163-39.26 
•09 
(.371) 29692-79.26.® 
-02 
(1) 29710-88.26.®' 
- -06 
®.(3) 38589-92.26 
•09 
(2) 37320-68.6.77 
-15 
(.5) 30005-3 4.26.77' 
- -01 
7 
49280-00 
21-25 
49301-25 
21-25 
49322-50 
(3) 37829-35.6 (- 8i).7t 
-00 
(1) 34870-17.26 
-24 
w.(l) 30559-83.26 
•14 
(2) 37534-58.6 (-Si).® 
-00 
(3) 37849-82.6.77 
-29 
®.(1) 39082-95.26 
-21 
(<1) 37554-87.6.® 
-32 
(<l77) 30444-37.26.® 
-07 
* This is also 3e.r2 (1) (8) the 90 A 2 linked F 2 . It is probably not (28i) D (2) but hides it. 
VOL. CCXX.-A. 3 I 
