Astronomy. ; 467 
[Norz.—Since the above was in type, the Astronomische Nach- 
richten for October 24th, No. 1864, has been received. It con- 
tains a notice of auroral spectra as observed at the Bothkamp 
Observatory by H. Vogel, which is dated August, 1871. In ordi- 
nary auroras 6 lines were seen, in a red streamers 7. The fol- 
lowing are the wave-lengths. given :— 
629°7 Very bright line. 
556°9 Brightest line of the semghien ee weaker 
i when the red line is ras pre 
538°2 Very faint ean tie ful.) 
523°3 Pretty bright | 
Very bright see the red line is present. At other 
times, as =“ as the last. 
500°3 Pretty bright hi 
from 469°4 { Broad band, brighter in the center. Very weak in 
to 462°9 : the red stream 
The line of wave-length 500°3 . aude the same observed by 
me, and given as 502. 
Vogel t thinks he has obtained evidence in support of the assump- 
tion that the auroral spectrum is an air spectrum, modified by 
conditions of pressure and temperature. 
e whole number of lines which have been seen and measured 
in the + eoaederigh of the aurora by different observers appears to be 
11, as follows 
No. anctintan: wiveloigic Observer. 
oe H. R. Procter. 
1. Bright red line 629°7 Vogel. 
627°9 Zoliner. 
623 Barker. 
562 Barke ; 
2. Brightest line in the 5DT Winlock. 
spectrum 556°9 Voge 
| 556-7 Angstrom 
3. Band 544 oa 
4. Ve faint lin §38°2 
ee 532 Alvan Olark, Jr 
5. Band (coronal line ?) +531 har ° 
523 oge 
6. Pretty bright line ; ine . Vol 
. : 518°9 Vogel. 
rker. 
8. Pretty bright line ; ae xe 1. et tee 
485 yan Clark, Jr. 
9. Band (F ?) a 482 A 
462°9 to 469°4 Vogel. 
464 
10. Band Winlock. 
11. Band (G ?) 434 Alvan Clark, Jr. 
