112 
PROFESSOR W. N. HARTLEY AND MR, W. E. ADENEY 
The Spectrum of Carbon. 
Scale- 
numbers. 
Description of lines. 
Wave¬ 
lengths. 
Remarks. 
29-47 
Very strong, short, slightly extended . 
4266-3 
52-93 
Strong, very short. 
3919-5 
55-85 
Weak, discontinuous, extended . . . 
3881-9 
This line is not given by Messrs. 
56-32 
Fairly strong , very short. 
3875-7 
Liveing and Dewar. Coin- 
cident with an air line. 
56-70 
Weak, fine, discontinuous .... 
3870-7 
81-57 
Weak, short. 
3589-9 
82-05 
/Weak, fine, discontinuous .... 
3584-8 
These lines are not given by Messrs. 
82-28 
(_ Weak, fine, discontinuous . . . . 
3583-3 
Liveing and Dewar. 
131-65 
/ Weak, very short. 
3167-7 
131-91 
\ Weak, very short. 
3166-0 
158-70 
Weak, very short, broad, nebulous . 
2993-1 
163-23 
Weak, very short. 
2967-3 
187-43 
/ Strong, short, extended. 
2836-7 
187-65 
L Strong, short, extended. 
2835-9 
206-20 
Fairly strong , very short, nebulous . 
2746-6 
230-34 
Weak, very short, nebulous .... 
2640-0 
264-84 
/ Strong, short, fine, extended . . . 
2511-6 
265-88 
\ Strong, short, fine, extended . . . 
2508-7 
274-78 
Sharp, fine, barely discontinuous, ex- 
tended. 
2478-3 
This line is ail but continuous. 
335-89 
Strong, short, wdth a nimbus 
2297-7 
It is the longest line in this 
spectrum. 
This spectrum was taken from a piece of very pure Ceylon graphite, which contains 
■> 
only traces of iron ancl of magnesium as determined by an analysis of the ash. No 
iron lines appear in this spectrum, and only four lines of magnesium, namely, those 
with wave-lengths 2801'6, 2796% 2794T, and 2789'6.* There are certain lines in 
Messrs. Liveing and Dewar’s spectra which are absent from ours, viz. : those with 
wave-lengths 2733% 2541% 2528-2, 2523% 2518% 2515-8, 2514-0, and 2506-6. 
* These have since been shown to belong to the spectrum of silicon. See “ Line Spectra of Boi’on 
and Silicon,” Proc. Roy. Soc., vol. xxxv., p. 301; also report presented to the British Association, 
Chemical News, vol. xlviii., p. 1 (W. N. Hartley, Nov. 1, 1883). Of the lines attributed to the arc 
spectrum of carbon by Messrs. Liveing and Dewar that to which they assign a wave-length of 2478'3 is 
the only line belonging to this element. Their measurement is identical with that which we have 
obtained from the longest line in the spark. 
