The Absorptio7i-Spectrum of Oxygen and a Neiv Law of Spectra. 159 
In the same way the tail of B is given by the formulae — 
14559-6 + 1 - U'l + 12Y. 
^^Tazl" of B.— 
Value 
of n. 
Frequency 
Calculated from 
14560-6- r'-^V 
Error. 
Value 
of 11. 
Frequency 
Calculated from 
14558-6- T— 
Error. 
0 
14522-6 
+ 0-2 
1 
14518-4 
+ 0-1 
1 
14516-4 
+ 0-2 
2 
14511-6 
2 
14509-6 
0 
3 
14504-4 
0 
3 
14502-4 
0 
4 
14496-6 
0 
4 
14494-6 
- 0-1 
5 
14488-4 
0 
5 
14486-4 
- 0-1 
6 
14479-6 
- 0-1 
6 
14477-6 
- 0-2 
7 
14470-4 
0 
7 
14468-4 
- 0-2 
8 
14460-6 
- 0-1 
8 
14458-6 
- 0 -2 
9 
14450-4 
0 
9 
14448-4 
- 0-1 
10 
14439-6 
+ 0-1 
10 
14437-6 
- 0-1 
11 
14428-4 
+ 0-2 
11 
14426-4 
0 
12 
14416-6 
+ 0-2 
12 
14414-6 
0 
In the B series there is again one observed line unaccounted for, viz., 
that at 14556*1 ; it has probably been wrongly observed. 
The a complex has been too little observed to work its formula out, 
but it is of the same type, with a head commencing at 15923-6 (double), 
and a pair series beginning at 15915*8 and continuing (after a break) at 
15894-9. 
The author has also found a connexion between the constants of A 
and B: the ratio {= (f) of the fundamental oscillation-frequencies is 
1*10586 for both pairs ; and the cube of this is the ratio of the coefficients 
of 7^^ viz., 0*25 0*175. 
This investigation shows that the vibrations of O2 are due to one 
system only, and that that system is very slightly unsymmetrical (to 
account for the pairs). Probably one oxygen atom has a few more 
electrons attached to it than the other has. 
11 
