114 PROFESSOR PIAZZI SMYTH ON 
CARBONIC ACID. Enp-on TuBE—continued. 
ue = 
Colour. Subject of Observation, Intensity. eave W.N. Place. | Impurities. Gonstiin ants ie Carbonic. 
Part 3—continued. : 
1 ; 47 446 
Pemy iinet 1 47 646 Oxygen ? A 
1 47 875 | Hydrogen | 
Faint band, . : ; : : } te oy 2 
Green. Fainter haze line, . A 0°3 48 559 
Very dark space intervenes. 
Exceedingly thin line in that space, 0:2 | 48 680 
Green band begins sharply; with 
a weaker spark it is followed by 5 } 48 841 Carb 
a faint Carbo-hydrogen Green 0°5 paaae 49 363 PRON 
—_-—_— Giant. Ends in faint haze, , . 
Faint band, . io a a6 Hydrogen ? 
P 0°5 50 251 
Faint hazy lines, . 5 { 05 50 475 
1:0 50 774 Hepdregenss Carbon 
: 0°8 51 110 ydrogen i i 
Faintest hazy bands, 05 51 542 |Hydrogen+?} Carbon? | 
0°3 # 51 784 | 
Glaucous Hydrogen, : , 3 | 52 237 Hydrogen 
Glaucous. 52 246 
Part 4. 
Glaucous Hydrogen, ; 5 | 52 256 Hydrogen 
Blue band, sharp beginning, . 4 52 510 Carb 
weakend, .  . O38 |} 3 53 030 bp . 
OS | = }| “53288 
il =o 54 207 Carbon ? 
Very faint bands, . 07 = 54 520 | 
0°8 = 55 149 
05 = 55 620 
! 
Blue. : Sharp beginning, . 3 56 224 
[aren Srazie ee Violet band, Faint ending, ; 0-3 | ¢ His 56 641 Carbon 
é 0-2 069 
Indigo. Faintest bands, . 5 < } 0-2 4 57 607 . 
Second ) Sharp beginning, 2 is, } 57 828 Carbon 
—_——_——_ violet band, § Faint ending, . 1 ah 58 256 Oxygen ? | 
Violet hydrogen, . i 2°5 ! 58 521 Hydrogen | 
Part 5. ) t 
Violet. Violet Hydrogen, . ; 3 1 58 591 Hydrogen 
Faint band, . : a + 4 one Carbon 
c u 59 576 
Faint band, . : 0:2 is, 59 961 
Faint band, . . es : } a Carbon 
Lavender. : 
Stronger grey band, . Ae Hr. 2 an Carbon 
i 
End of Spectrum. 
Mems.—Hydrogen and some probabilities of Nitrogen are the only impurities here. 
This spectrum is very rich in Carbon bands ; but weak in Oxygen, and still more in Carbo-Hydrogen. 
Carbonic Oxide looks the same identical thing as the above Carbonic Acid ; or as explained by THALEN, the Carbonic Acid 
spectrum is that of Carbonic Oxide, one portion of its oxygen being inert. 
Both Marsh-gas and Olefiant-gas resemble the above in the Carbon bands, but differ by having the lines and the bands of 
Carbo-hydrogen also and strongly. 
The commencing red lines were re-observed on April 7: 1st at 35 839; 2nd at ee rd ; and ord at } rf oa : 
