RECORD OF AURORAL PHENOMENA. 73 



This was also one of the rare instances of the Aurora being seen to the southward of our zenith." 

 —2 Beechey, 560. 



N. B. — 1. Ilad every appearance of being between the clouds and the earth. 



2. This was one of the rare instances of the Aurora being seen to the southward of our 

 zenith. 



At Sea.— Lat. 66° 30' N. Long. 59° W. September 23, 1818. Robertsox. 



"About ten in the evening, the Aurora Borealis was seen in the true south horizon. The horizon 

 was first illuminated like the rising or setting of the moon behind a cloud, or rather like the 

 illumination of the atmosphere caused by great fires. This extended four points of bearings. 

 Rays were soon after darted up perpendicularly in bundles to 20° altitude. The Aurora spread 

 to S. E. without darting rays, and soon after disappeared." — 1 John Ross (Lieut. Robertson), 

 App. 120. 



Behring's Sea.— Lat. 66° 30' N., Long. 163° 00' W., to Lat, 71° 23' 31" N., Long. 156° 21' 30" 

 W. Autumns of 1826 and 1827. Beeciiey. 

 "We had frequent opportunities of observing the Aurora Borealis in the Autumns of 1826 and 

 of 1827. From the 25th of August until the 9th of October, about the time of the departure 

 of the Blossom from the northern regions in both years, this beautiful meteor was visible on 

 every night that was clear, or when the clouds were thin and elevated. [In 1826 it was visible 

 on twenty-one nights; in 1827 only eleven.] It is remarkable that, in both years, its first 

 appearance was on the 25th August. The season of 1826 was distinguished by an almost 

 uninterrupted succession of fine weather and easterly winds, and that of the following year by 

 continued boisterous weather and winds from the westward. In the former year, the weather 

 being fine, the Aurora was more frequently seen than in the latter; but iu 1827 the displays 

 were brighter, and the light more frequently passed to the southward of the zenith. It never 

 appeared in wet weather. 



In 1826, when, as before mentioned, the weather was settled, the Aurora generally began in the 

 W. N. W. and passed over to the A". E. until a certain period, after which it as regularly com- 

 menced in the A". E. and passed to the N. W. ; whilst in 1827, the appearance of the meteor was 

 as uncertain as the season was boisterous and changeable. 



The period when this change in the course of the light took place, coincided very nearly with that 

 of the equinox ; and, as the Aurora Borealis has been supposed to be affected by that occur- 

 rence, we imagined that the change might be in some way owing thereto ; but the irregularity 

 of the meteor in this respect, in 1827, gave a contradiction to this hypothesis. It was, how- 

 ever, uniform in making its appearance always in the northern hemisphere, and generally in the 

 form of elliptical arches from 3° to 7° of altitude, nearly parallel with the magnetic equator. 



These arches were formed by short perpendicular rays passing from one quarter to the other with 

 a lateral motion, or by their being met by similar rays from the opposite direction. The arches, 

 when formed, in general remained nearly stationary, and gave out coruscations which streamed 

 towards the zenith. "When at rest, the light was colorless; but when any movement took place, 

 it exhibited prismatic colors, which increased in strength as the motion became rapid. The corus- 

 cations seldom reached our zenith, and more rarely passed to the southward of it, but when that 

 occurred the display was always brilliant; on one occasion only they extended to the southern 

 horizon. 



We remarked that when any material change was about to occur one extremity of the arch became 

 illuminated, and that this light passed along the belt, with a tremulous hesitating movement, 

 toward the opposite end, exhibiting the colors of the rainbow. An idea may be formed of this 

 appearance, from the examination of the rays of some molluscous animals in motion, such as the 

 nereis, but more particularly the beroes. Captain Parry has compared its motion to the waving 

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