82 C. A. Young— Observations on Encke’s Comet, 
measures. ‘I'he numbers given relate to the bright, compara 
tively well-defined, less refrangible edges of the bands. 
Kirchoff’s scale. | Angstrom’s scale. 
Date. Istband. | 2d band. | 8d band. | istband. | 2d band. | a 
Dec.1,-| 1295 | 1645 | 9970 | 8593 5174 | 4698 
Dec. 2,.] 1240 | 1650 ee 5575 5173 ae 
Dec. 5,.| 1245 | 1640 2265 5569 5178 fir 
Dec. 6,| 1250 | 1645 2260 5563 5174 ae 
Means,_| 1240 | 1645 2265 || 5575 | 51745 | 4702 
a ee OS ae = 
Spectrum of Encke’s Comet. 
ene es eee aT 
Kirchoff’s scale. 211 2|0 1:9 ioe 14 1|3_ 1/2 J 
| og ! 
4\9 bu LZ BSBA HJo 9/6 OIE 
Angstrom’s scale. 
‘ : m 
The figure * gives an idea of the appearance of the spectru 
and the position of its bands, 
* The irregularity observable in the spacing of Angstrém’s scale at the bone 
of the diagram is no fault of the draftsman or engraver. but ap scans ‘hel 
The irregularity, however, is really in the scale of Kirchoff, the prisms 0 
fas 
