Second Spectrum of Hydrogen. 

 Table (continued). 



341 



Wullner's Acetylene Spectrum. 



Spectrum of Carbon 

 Oxide. 



Spectrum of Hydrogen 



Description. 



channelled band occur- 

 ring in the spectra of all 

 gases containing carbon, j 

 showing the fine lines 

 which are so beautifully \ 

 seen in the bands of the 

 carbonic-acid and car- 

 bonic-oxide spectra. This \ 

 band, however, is di- 

 stinctly narrower than 

 in the spectrum of car- 

 bonic acid. It is bounded 

 by a sharp line at 5550 



A broad green field, 

 which, like the first hy- 

 drogen spectrum, shows 

 a large number of lines, 

 follows, and then the 

 green band finely shaded, 

 as in the carbonic-acid 



spectrum, begins at 5200 



which, however, like the 

 greenish-yellow band, is 

 only half as broad as in 

 carbonic acid. 



The same holds good of 

 the following carbon 

 bands : the blue one be- 

 ginning at 4834 



the first violet at 4510 



the second violet at 4393 



Between these bands 

 the spectrum is similar 

 to the band-spectrum of 

 hydrogen; as is also 

 the case with ethylene 

 and marsh-gas, although 

 there are differences in 

 detail. 



X. 



5197 



4833-5 

 4509-0 

 4394-0 



Remarks. 



Brightest band 

 of CO. 



X. 



5536-6 



Remarks. 



We see from this comparison that Wullner's so-called ace- 

 tylene spectrum contains scarcely a single line or band which 

 does not occur either in the spectrum of carbon oxide or in 

 the second hydrogen spectrum. It is exactly the brightest 

 lines of this last spectrum which appear here ; as indeed must 

 be the case, since the weaker lines are concealed by the broad 

 bright bands of the superposed carbon-oxide spectrum. That 

 these bands belong to carbon oxide, and not to carbon as 

 Wullner thinks, may be considered as a settled matter. Their 



