34 
THE ASTEONOMEE EOYAL, W AVE-LEN GrTHS 
For line B . . . -}- 320 
C . . . +147 
D. . . +142 
E . . . +97 
F . . . +123 
G . . . +213. 
And, after making a preliminary calculation, the following corrections were found to 
be necessary : — 
For £=-0-6, +306= +140+ 124x(l+i) 
0- 7, +142 = +140+ 74xife 
1- 0, +140 =+140 
1- 5, +109= +140- 302 X-^ 
2- 1, +149 = +140+1109 Xtto 
2-9, _ 98=+140-1077 X (i+^). 
The factors in the last column are f0 ’6], [0*7], &c. respectively. 
Then, using the number +140 as a general correction, and using the numbers of the 
last column for “Correction for &=0'6,” “ Correction for #=0*7,” &c. in the general 
formula (or, in other words, multiplying the 3rd, 4th, &c. columns of the Table, by 
(1+y), yy, &c.), the following special numerical corrections are obtained. 
Corrections to the wave-lengths as originally computed. (The unit of the corrections is 
the same as the unit of the last figure of the computed wave-lengths in millimetres.) 
Jc. 
Correction. 
Jc. 
Correction. 
Jc. 
Correction. 
0-0 
+ 8857 
1-0 
+ 140 
2-0 
+ 55 
0-1 
+ 5891 
1-1 
+ 174 
2-1 
+ 149 
0-2 
+ 3750 
1-2 
+ 191 
2-2 
+ 283 
0*3 
+ 2257 
1*3 
+ 184 
2-3 
+ 447 
0-4 
+ 1269 
1-4 
+ 154 | 
2-4 
+ 616 
0-5 
+ 654 
1-5 
+ 110 
2-5 
+ 761 
0-6 
+ 305 
1-6 
+ 61 
2-6 
+ 832 
0-7 
+ 141 
1-7 
+ 18 
2-7 
+ 770 
0-8 
+ 92 
1-8 
— 4 
2-8 
+ 493 
0-9 
+ 103 
1-9 
II 
+ 6 
2- 9 
3- 0 
- 97 
-1116 
With these numbers, a curve was laid down, and the corrections for every 0 - 01 of Jc 
were obtained graphically. Between these, the corrections for all the individual lines 
were interpolated numerically, and were applied separately to each computed wave- 
length. Every number which is presented in the following Tables is affected with the 
correction. 
The agreement of the computed numbers with Ditscheiner’s, or with Angstrom’s (after 
multiplication by the proper factor), as far as they admit of comparison, is not so close 
as I expected. For the lines B, C, D, E, F, G, the accordance with Ditscheiner’s 
