112 PROFESSOR PIAZZI SMYTH ON 
AMMONIA. Enp-on Tuse. NH,—continued. 
Colour. Subject of Observation. Intensity. Appear. | wax. Place. || Impurities. poesia ents Vad 
Tart 4—continued. : 
Glaucous. Distinct line, : : 1:0 | 50 512 Nitrogen 
Line, beginning haze band, 2°0 fi, | 50 668 Carbon ? Nitrogen ? 
Strong line, . : : : 20 l 51 064 Nitrogen? | Ammonia ? 
Faint line close up to above, . 1:0 ; 51 128 Nitrogen ? 2 
Thin line, . : : : 5 1:0 | 51 252 2 2 
Next double line followed by extra . ; 51 472 , 
black space, A tag er 4 a ll 51 534 Hydrogen 
Decreasing band of thin faint lines, 07 ie, } - asd Nitrogen 
Glaucous Hydrogen vividly bright, 10 S| 52 252 Hydrogen 
Faint haze beyond, 0°3 ri 52 590 Carbon ? 
Line beginning band, 2 fi: | 52 782 Nitrogen 
Line beginning grand band, . : 3} Fu. 53 841 ohh 
Epaceinebadet Fe ie ae eat ee 54 310 Nitagen 
Faint line, ‘ 1:0 1 54 480 Nitrogen ? ne 
Glaucous. A notable wide and blue double 2 54 670 ‘ a 
ee ae a ee 2 he 65 one Rstogens 
Bine Line beginning graduated band, 2°5 E: 55 556 Nitrogen 
‘ Line beginning grand blue band, . 3:0 E. 56 620 Nitrogen 
Indigo. Part 5. August 2, 1879. 2 
peace ee Peeing a sae 3 L. 57 BBS : Nitrogen 
Another, : 6 : i : 3 k: 58 354 Nitrogen 
but closely followed by violet . 
Violet. hydrogen, . , : : A I 58 a8 Hydregen 
End of band on which violet 
| hydrogen is projected, : 03 59 208 
——-- ——_ Line beginning another band, 25 fiis., 59 500 Nitrogen ? 
Faint hazy line, ; - 1 ; |. 60 294 || Marsh-gas ? 
Line beginning band, : ; 1122 lis, 60 480 Nitrogen 
Line beginning band, . ; 5 1185) lis, 61 290 Nitrogen 
Lavender. Mere haze band, . ; ; : 1 iE 62 140 Nitrogen 
Weak hazy line, beginning a faint , 
indistinct band, : ; 1s Hee | 2890 f 
| Hazy beginning of a band, 07 5s, 63 750 f 
Spectrum ends here, excepting only some ultra-faint ghosts of haze-bands, derived apparently from false reflections. 
Temperature of chamber and apparatus=64°'0 Far. Spark=0°7" long. 
Impurities here are very few and weak. 
The constituents Hydrogen and Nitrogen are abundant; but the latter seems to tend more towards lines than bands, 
through all the middle of the Spectrum, than in a pure Nitrogen tube. 
This Ammonia tube still further contrasts with the late Alcohol tube, inasmuch as there is here no trace of the combustion 
spectrum of carbon, carbo-hydrogen, &c. ; and we may note at the same time how superior in brilliancy is the Glaucous, to 
the Red, hydrogen line ; a symptom of higher electric temperature here, than in the Alcohol spectrum, wherein the Red was 
the brightest of all the hydrogen lines. 
