, Account of an Aurora Borcalis. 



135 



Having made the foregoing sketch. I again returned to view the 

 Aurora, which had somewhat changed its appearance. 



Both arcs or belts were now less distinct, the lower one almost 

 obliterated, but still its place was well marked by the arch of vapor 

 below, which was darker than ever. Three large spots of intense 

 light now displayed themselves, one on the horizontal chord, and 

 one on each side of the lower arch, whilst this lower zone shot out 

 innumerable pencils and floods of light from its dark nucleus, the 

 upper zone also darting forth long lines of brilliant rays ; all these 

 rays from both bands, moving in a very stately march or progression 

 from east to west. 



* 



Towards the southern and western portions of the heavens, all 

 was clear blue-black starlight, Orion being particularly brilliant; 

 the north was as if overspread with a thin veil, through which the 

 stars were barely visible. 



I watched these alterations of the phenomenon until after ten ; 

 and the last I observed presented this form ; after which the arches 

 became less distinct, and eventually, with the exception of the great 

 arch, passed away. 



In this fourth change the Aurora, it will be observed, resumed its 

 three arches, but they were no longer concentric, the third being 

 broken on the right into a portion of a fourth. Between the sec- 

 ond and third the darkness was the darkness of blackness, whilst the 

 third arch was light itself; but the lower arches were not so bright, 

 and the lower nucleus was only darkish, which was contrary to every 



