( 805 ) 
APRN DIEX I. 
COLOURED-GLASS SERIES OF SPECTRA, WITH PRISM 2; 
DIsPERSION=1°:2, from A to H of the Solar Spectrum. 
Magnifying power of inspecting telescope= 10. 
Order, Red to Violet. 
Decemier 1876, January 1878. Bar.=29°7. Ther.=61-:0° generally. 
the foundation of the continuous spectrum of a union-jet gas (Coal-gas) burner viewed 
edgeways. 

All the series taken on 
Slit opened to 45 space of D to E, and focussed on the D line. 

COAL-GAS FLAME’S CONTINUOUS SPECTRUM. 

False glare from internal reflections 
True but faint black-red light 
Strong red light seen at 
D slit, red side thereof 
» yellow side 
Maximum Licut _ é : 
Green light ends, blue begins at 
Blue Light ends, violet light begins 
All light ends af 

Intensity, 
Max. =10. 
Wave-number 
in Brit. inch. 
Colour Region by 
Wave-number. 


24642 
24-965 
25°145 
25°823 
25°873 
25:940 
26°220 
27°670 
28°430 

First black-red light . 
First decided red light 
First strong light 
Maximum LicHt 
Red-Orange colour ends on first side of D 
line 
Green yellow colour begins on second side 
of D : : : 
Faint dark band in the ereen 
Darkest part of band . ‘ 
Dark band ends and violet light ‘begins 
VIOLET light culminates ‘ 
End of all light 
VOL. XXVIII. PART III. 

596 
864 
305 
827 
384 
053 
948 
140 
516 

Ultra Red 
Crimson Red 
Crimson Red 
Amber 
YELLOW 

YELLOW 
Citron 
VIOLET 
Lavender 


0-1 24-913 | 30 581 | Crimson Red | 
0:2 25:050 | 32 787 | Crimson Red 
16 25:240 | 35 971 | Red 
67 25770 | 42 194 | Amber 
6°5 25°823 | 42 827 | Amber 
6°4 95°873 | 43 384 | YELLow 
3°8 26°560 | 50 000 | Glaucous 
1:8 26:970 52 966 Glaucous 
22 27°190 54 645 Glaucous 
2:3 27°745 58 928 | VIOLET 
0:0 28°280 63 291 LAVENDER 
10 8B 
