156 PROFESSOR PIAZZI SMYTH ON 
NITROUS OXID E—continued. 
se : ; Appear- . es Constituents | Left bp! 
Colour. Subject of Observation. Intensity. W.N. Place. I rities. 
olour ubject 0 servation n ity, | ance. mpurilies. dissociated. /_Aissoelated. | itrous Nitrous Oxide, 
Part 83—continued. | 
Citron. Line among fainter ones, : : 2 als 46 889 Nitrogen 
Broad faint resolvable band, . 2 il gals Il mG rh Nitrogen 
Bright line on faint haze, 2 | 47 850 | Hydrogen? Oxygen ? 
Resolvable fainter haze intervenes. 
Haze band ended by a line, . : 1 a ee Nitrogen 
Green. Bright beginning of a grand band, 6 48 850 Carbon 
A line just visible near middle of Carbo- 
that band, 5 ; : 2 | 49 170 Hydrogen 
Part 4. 
From Green Giant’s place, there is ; 
faint haze to this line, : i | BOs Nitrogen 
-————--—— Haze intervenes, then this line, 1 | 50 437 Nitrogen 
Fainter haze, andthen thisline-band, 1 51 030 Ni itrogen 
Do. do. do. 1 51 632 Nitrogen 
Faint haze follows. 
Glaucous Hydrogen, not very bright, 4 I 52 230 Hydrogen 
Glaucous. 
Beginning of a flat band, 3 52 505 Carbon 
pene beginning of a graduated 3 52 752 Nitrogen 
Sharp beginning of a band, 2°5 Hs, 53 794 Nitrogen 
Beginning of a flat band, 2 54 420 
a cae beginning of a graduated 2 54 640 Nitrogen 
Sharp beginning ‘of a _ graduated | 
single band, (age 33 is 55 484 Nitrogen 
Blue | 
| Beginning of a flat band, 2 HH 56 280 Carbon 
3rd case j Sharp beginning of a : s 
era Se isk Re d, 2°5 i. 56 610 Nitrogen 
Sharp beginning of a gr aduated : 
Indigo. an a ' 2 i, 57 560 Nitrogen 
do. 15 is, 58 340 Nitrogen 
—_——_— ve aene ts i th 
| ee ydrogen ue s in on the 2 j 58 528 Lae 
Part 5. 58 524 
Violet. Violet Hydrogen, . : : : 2 I 58 519 
Lier rib, pean graduated 3 i, 59 530 Nitrogen 
Very faint line, . : , ; 0'3 | 60 278 Carbon 
—_—-——— Rib beginning band, wef) i 60 500 Nitrogen 
| Do. dos. 15 61 350 Nitrogen 
: Do. do. 1:3 +, 62 102 Nitrogen 
Lavender. Do. do. . 6 : ' 0°9 ts 62 672 Nitrogen 
Do. don. : : : 0°5 63 706 Nitrogen 
| Problematical, 01 64 560 Nitrogen 
End of Spectrum. 
This spectrum is very like that of Nitrogen ; but with less than half the amount of Hydrogen impurity, and a similarly 
small proportion of Oxygen, though that should be present as a constituent dissociated, at the same time that the Nitrogen — 
was freed; but Oxygen is undoubtedly a bad illuminator. There are also large traces of Carbon, and smaller of Carbo- 
hydrogen, impurities. 
