244 THE ALKORA BOREALIS, 



few minutes before 10 o'clock, P. M., as several observers at this place 

 directed their attention to the northern heavens, they vi^ere delighted to 

 see an arch, then about 45° high at its apex, moving rapidly upwards to- 

 wards the zenith, whilst the streamers, extending up from the horizon 

 to the arch, caused the whole appearance to resemble that of a -'rain of 

 fire" descending from a burning cloud. In a few minutes, (the time was 

 not noted accurately,) the arch reached the zenith, where it appeared 

 about 10 o'clock, and from which it afterwards slowly moved a few de- 

 grees farther southward. In this position it remained until nearly 11 o'- 

 clock, and there presented that singular wave-like motion westward al- 

 ready alluded to, and at times sending forth short branches, like stream- 

 ers, towards the north-west. The polar distance reached by the moving 

 arch before it becomes stationary, is various at different times; being, as, 

 it would seem, equal to the repulsive power exerted from the magnetic 

 focus or the origin of the streamers. It does not, however, often reach 

 farther southward than the zenith of latitude 35°. But such an altitude 

 would, to one in high latitude, appear to be in the southern horizon, so 

 that the apparent height may vary from 0° up to 180°. 



From the language of D. K., in the June nnmber of this Journal, we 

 would infer that the arch was formed near the zenith. This is undoubt- 

 edly the point at which most observers first noticed it ; but to us, at this 

 place, it appeared to arise from the northern horizon. Several other in- 

 stances of a similar kind have been witnessed by us on former occa- 

 sions, and other observers have given an account of having witnessed 

 the same origination of arches. It, indeed, appears to us, probable that 

 the "corona" and arches have a common origin, viz : luminous matter 

 transported from the focus of power in the northern horizon. In the 

 case of some of tlie arches, and in most of the coronas this is apparent 

 to the senses ; and in other cases, this sudden appearance and westward 

 motion may arise from a peculiar condition of the nebulous matter un- 

 der which it becomes visible. 



7. Another remarkable circumstance in reference to the Aurora Bo- 

 realis is the gigantic scale on which it displays itself. In many instances, 

 indeed, its visible effects are witnessed alone in high polar latitudes, but 

 not unfrequently they are seen as far south as within 30"^ degrees of the 

 equator. And its extent in longitude is even greater than that in latitude. 

 The aurora of Nov. 14th, 1837, was witnessed in this country from St. 

 Louis, Mo., to Maine, and at the same time in England, and probably over 

 the whole continent of Europe, thus extending nearly half way round the 

 globe. And were it not for the interference of the superior light of the sun 

 whirh renders il invisible during the day, it is highly probable that it would 



