Mr. J. S. Ames on some Gaseous Spectra. 55 



Calc. 



;; A 



=3647-20 '" . 



m 2 — 4 



Observed. 



C 



6564-96 



6564-97 



F 



4862 93 



4862-93 



G' 



4341-90 



434200 



h 



410310 



410311 



H 



3971-4 



3971-40 



a. 



3890-3 



3890-3 



/3 



3836-7 



3836-8 



y 



3799-2 



3799-2 



S 



3771-9 



3771-9 



e 



3751-4 



3751-3 



I 



3735-6 



3735-3 



n 



3723-2 



3722-8 



e 



3713-2 



3712-9 



The agreement is striking ; and it is possible that atmo- 

 spheric refraction may fully account for most of the discre- 

 pancies. 



As stated before, the formation of series similar to this one 

 of hydrogen is a feature common to many spectra. Balmer's 

 law with slight modifications probably applies to all. The 

 similarity between them is evident at once to the eye ; but 

 mathematically it is more apparent if we consider the wave- 

 numbers, or rather their differences. So, for purposes of 

 comparison, I will give these for the hydrogen series. The 

 values are corrected, as before, for atmospheric refraction. 



N. AN. 



O 1523-32 



F 2056-37 533-05 



G' 2303-09 246-72 



h 2437-18 134-09 



H 2518-00 80-82 



u 2570-50 52-50 



/3 2606-34 35-84 



y 2632-13 25-79 



d 2651-18 19-05 



e 2665-74 14-56 



I 2677-16 11-42 



n 2686-15 8-99 



6 2693-32 7-17 



As to the secondary spectrum of hydrogen, Hasselberg has 

 shown, conclusively I think, that it is not due to impurities, 

 but to hydrogen itself. All of my observations on this point 

 are in complete accord with his. But in his list of lines there 

 are two mistakes. That the line at w.-l. 4347*71 (4347'K) on 

 his map) is a mercury one is now certain, as it appears strong 

 in the arc-spectrum as photographed by Prof. Rowland. 

 Then, on Hasselberg's map and in his list of wave-lengths, 



