RECORD OF AURORAL PHENOMENA. 21 



and its legs seeming to rise out of the ocean. From this arch usually diverge rays towards the 

 zenith, or a point in its vicinity. This description of Northern Light is colorless; and I think 

 I have observed that it usually precedes, but still oftener follows after, some great change of 

 temperature, especially from thaw to frost. 



The other sort of Northern Light, which, still more than the former, seems to stand in connec- 

 tion with barometrical changes, flits from place to place in the semblance either of light lumi- 

 nous clouds agitated by the wind, and through which the light appears to diffuse itself with a 

 sort of undulating motion, or of flaming rays, flashing, like rockets, across the firmament, most 

 commonly upwards in the direction of the zenith, or, finally, like a serpentine or zigzag belt 

 of vivid, undulating light, frequently colored, which at one moment is extinguished, and the 

 next relit. The most beautiful of this class of phenomena, meanwhile, is the Corona, a lumin- 

 ous ring near the zenith, of from 2° to 3° in diameter, with rays diverging in every direction, 

 like prolonged radii, from its centre. This highly interesting phenomenon seldom lasts longer 

 than a few seconds, at the expiration of which an explosion, as it seems, takes place, scattering 

 the luminous matter in every direction, and extinguishing it. The centre of the Corona I found 

 to be invariably situated to the east of the meridian, at an elevation of from 81|° to 82|° above 

 the horizon. 



When the Aurora displays itself in all its splendor, its light is brighter than that of the full moon. 

 It has been asserted, that this phenomenon is sometimes accompanied by a low, hissing noise. 

 I myself, in fact, have often heard the sound, but am satisfied it has nothing to do with the 

 Aurora, but proceeds partly from the ice, partly from the wind sweeping over the snow and 

 ling-clad hills. 



Whenever a more than usually vivid Aurora displayed itself, I made a point of taking measures to 

 observe its effect on a magnet suspended by a silken fibre, but never detected any agitation or 

 alteration in the direction of the latter, that could be attributed to this cause; though, I must 

 add, that in making some like experiments, in the years 1823-24, at the Colony of Good Hope, 

 situated in lat. 69° 14', I did think that some such effect was perceptible. 



That the substance-matter of the Aurora Borealis is liable to being acted on by the winds prevailing 

 in different atmospheric strata seems evident, from the phenomenon itself, and as the changes 

 of the weather depend again, in some degree, upon the winds, it is probable that a connection 

 exists between them and the phenomenon of the Aurora. Many have hence inferred, that the 

 appearance of the latter may safely be regarded as a prognostic of the former. This opinion, 

 however, is, as far as I am aware, by no means well founded; aud, in fact, all that may be 

 securely relied on, with reference to this subject, is what follows: — 



1. When the Aurora Borealis is vivid, and displays a variety of colors, boisterous or bad weather 

 may be expected, and the wind may be looked for from that quarter where the Aurora has dis- 

 appeared, or been extinguished. 



2. When, after a long absence, an Aurora Borealis appears between S. W. and S. E. in the form of 

 an arch, from 10° to 20° high, and glowing with a steady light, it is a prognostic of approach- 

 ing frost. 



The Greenlanders have a singular superstition connected with the phenomenon of the Aurora 

 Borealis. They conceive it to be the spirits of the dead, playing at ball with the head of a 

 walrus, and fancy that it draws nearer to them when they whistle, — a superstition at all events 

 not more absurd than the idea long, and, indeed, still, prevalent in some parts of Europe, of its 

 being ominous of war, pestilence, or famine." — Graah, p. 52. 



Beresov (Russia).— Lat. G4° N. Long. 65° W. December 1, 1828. Erman. 



"In order to determine the magnetic declination, I observed, about eight o'clock in the evening, 

 the passage of the pole-star through the transit instrument. A few minutes after the observa- 

 tion was concluded, the clouds, which had hitherto obscured the lower part of the northern sky, 

 disappeared, and we saw in their stead, a brilliant Auroral light. 

 Towards the horizon there was still some darkness, but above that there was bright light, which 



