
IN PRACTICAL ASTRONOMY, SPECTROSCOPICALLY EXAMINED. 327 
DIVISION IJI—YELLOW MEDIA. 
1. IODINE. 
Tincture thereof diluted in water, March 9, 1878. 

COAL-GAS LUMINOUS FLAME as foundation. 


imteniity. | #/ Vin tie fact, | “Wavesnenber.” 
False red glare 0 24°86 29 087 | Ultra Rep 
First true red light 1 25:18 33 102 | Crimson RED 
Slit by sodium light, 1st side lea 26:01 43 015 | YELLow 
5 $ 2d side ifah 26°03 43 203 | YELLOW 
Maximum Licut, YELLOW 12 26:03 43 403 | YELLOW | 
End of all light at violet . 0 28°46 62 712 | Laven. Gray 





Solution of ,4, strength, shows only one band, stretching from red to citron, dully. 




Light begins 0 25°31 34 758 | Crimson RED 
Maximum Licat 5 25:99 42 992 | AmBER 
End all 0 26:44 | 47 529 | GREEN 
Solution of ,45 strength. 
Light begins 0 25°30 34 626 | Crimson RED 
Maximum LIGHT 4 25°68 39 526 | ORANGE 
End all 0 26:04. 43 497 | YELLOW 

2. BICHROMATE OF POTASH.—March 12, t=660. 
Solution in hot water; very like iodine, but brighter and yellower; and giving 
lighter and narrower band in spectrum. 

Solution = zy. 



Intensity. iss 
Light begins ; 0 25°30 
Maximum Licut and salt line 10 26:00 
End all 0 26°38 
Wave-number 
in Brit. inch. 
Colour Region by 
Wave-number. 

04 626 
43 103 
46 948 

CRIMSON RED 
YELLOW 
CITRON 



