W. Bagge Apeote nie of the Flame of Hydrogen. 1238 
line is seen to be the more refrangible limit of a group of 
fine lines shading off towards K. 
e ultra-violet group when carefully compared with the 
group.in the spectrum of pure drogen, shows several 
small differences. I am inclined to believe that there is the 
superposition of a second fainter group. There is strong 
evidence of this in some spectra of hydrogen taken under 
other conditions. There is also a broad band less refrangible 
than the strong line at G, and the light extends from this line 
on its more refrangible side. 
A double Bunsen burner eines form) with a strong 
blast of air was oa fitted up. The spectrum was taken of 
the intense blue flame. It resembles t e one last described. 
All the Merced features are intensified and a continuous 
spectrum and groupings of very fine lines fill up all the in- 
tervals between the groups already described, so that there 
is an unbroken strong spectrum throughout the whole re- 
gion meine falls upon the plate. 
irit lamp was arranged before the slit. The spec- 
fae is eibatts the same as No. 38, but as it is less in- 
tense only the strongest lines are seen. The water group, 
the strong line at G, and the pair of lines rather more re- 
frangible than K, are seen. Probably with a songe r expo- 
sure the finer lines would also show eit 
The distinctive features of peeing No. 3 appear to be 
connected with the presence of carbon 
Table of Wave-lengths of the Principal Lines of the Spectrum of Water.—No, 1. 
3062 3090 3117 3142°5 3167 3198 3232 
3068 3094 3122°5 3145 3171 3201 32425 
3073 3095 3127 31495 3175 3207°5 3252.5 
3074 3099 - 3130 3152°5 3180 3211 3256 
3077°5 3102 3133 3156 3184 8217°5 3262 
3080 3105 3135 3159°5 3189 3223 3266 
3082 3111 3139 3163 3192°5 3228 3276 
2869°5 2897 29299 2959 2994 3029 3271 
2872.5 2904 2932°5 2966 2999 3081 3429°5 
2876 2907°5 29355 2967°5 3002 3039 3473 
2880 2910 2940 2970°5 3005 3042 
2883 2913 2943 2975°5 3010 3046 
2887°5 2917°5 29447 2981 3013 3051 
2892 2922°5 2951 2989 3017 3057°5 
2895 2925°5 2955 2991 3019°5 | 3246 
Wave-lengths of other Lines in Spectrum.—No. 3. 
3872 3890 4310 
