J. H. Lefroy on the Aurora Borealis of 1850-1851, 155 
those remarkable instances of the simultaneous absence of cloud, 
and intense development of aurora over a very large part of the 
whole northern hemisphere, which, from their frequent occur- 
rence appear to have more than an accidental connection. It was 
seen at every station, with exception only of the Pelly Banks, from 
the polar circle to the United States, where no less than thirty- 
eight stations have forwarded accounts of it to the Smithsonian 
Institution ; it extended also to Europe, having been recorded at 
Sandwick Manse, Orkney. The display of February 28th, was 
almost as universal. It is remarkable that in many cases the phe- 
nomenon was first seen, in absolute time, at the most eastern Sta- 
tions, notwithstanding the earlier commencement of darkness. at 
the extreme north, where the difference of Jatitude in some cases 
mere than compensates the difference of longitude ; it would ap- 
pear from this that the aurora does not commonly appear at & 
station upon any meridian until that meridian generally is in dark- 
hess; a result which if established, by the whole body of evi- 
dence, will be both new and interesting. For example, in the 
following list I have entered the hour of sunset in meantime of 
Gottingen at each station, and the hour at which the aurora 1s first 
recorded in the same; it is not to be supposed that each observer 
seized the exact time of first visibility, but in two of the exam- 
ples at least the general result is sufficiently clear; namely, that 
it was seen at the lower and eastern stations sooner than at the 
northern but more westerly stations, although there is no reason 
to be given why it should not have appeared at the latter, as soon 
as at the former, daylight having ended there :— 
TABLE 
s Feb. 18, 1851. | Feb. 28, 1851. 
. January 27, 1851, © Decl. -114. © Decl. -8. 
ecl,—18}°, Eq.-13”. 14”. rae: 
© Decl. ~18}°, Eq. 18” Eq. -1 a oad 
ame sns on nN ye 
W.Long§ Auror® | cunset. Aurora Sunset. fret 
paige se cy ys ee Gortinger.| gion, {Gottinge™| seen 
oronte,....... 43°39’ 2517 P1056 | 19°00} 11:26 | 1400) 11:39 | 1600 
lalifax, 2... .,|44 89/4414} 1001 | ....] 1018 | 1140) 1078 | eee 
Meee; a... 49 |-4:45 | 10°14 | 1425} 10°35 | 1224 rr 12. 
ewfoundland, .|47. 33 |-8:31 | 8 voi ose, | 20 ‘57 | 13°55 
fichipicoton,.../47 56 | -5-40 | 11+ 11°50, | 1040 | cpar | 1se0 
loose Factory,.|51 10| 5:24 | 10°39 | 1454] 1117 | 1244 12-00 | 13°01 
lartin’s Falls, ..'51 52 | 5.474 1058 | 1490] 11°36 | 1801} 1800) 12° 
\thabasea,. .... 58 43| 725 | 12:03] 1430} 13:16 | 155 S41 | 15°58 
deg Pelly,61 30] 840 | 15-08 | 21°30 ob ot a 
ort Si ».{61 51} 806 | 1221] ..--] 3 1658) 16-27 | 18-0! 
nivepn Ie 66 00 3 11321 | 20-00] 1456 | 1858} 15°27 | 1803 
94 
Confidence, 66 54 | 7-55 | 11:21 | 1700] 12:55 | 3 bat ak Aas. 
’ecl’s River, .. 67 97| 858 1 19°19 | 1688} 1950 | 1788| 1431 |at dark 
S 
great majority give direct support to the inference I have drawn, 
and there are ier or no instances contradicting it. The question 
