Notice of the late Aurora Borealis. 1 09 



by W. was so brilliantly illuminated as to appear like the re- 

 flection of a great conflagration, whilst the white coruscations 

 which flashed through the atmosphere quicker than sheet light- 

 ning in sultry summer evenings, formed whole but irregularly 

 shaped arches from these points of the horizon through the ze- 

 nith nearly. At one A. M. lofty perpendicular columns emana- 

 ted from the aurora in the western point ; and at this time the 

 northern hemisphere was filled with long and short sti earners va- 

 rying in width and brilliancy, and often terminating in very point- 

 ed forms. The coruscations from the N. E. and W. frequent- 

 ly met each other in the zenith, and enlightened the scattered 

 portions of cirrostratus even to within thirty degrees of the south- 

 ern horizon ; and from the clouds being stationary, it is proba- 

 ble that the atmosphere was serene and undisturbed in their vi- 

 cinity. Soon after 2 A. M. the aurora grew faint and gradually 

 disappeared. The lustre of the stars of the first, second, and 

 third magnitude was very little diminished in any part of the 

 heavens where the vivid flashes of the aurora intervened. The 

 diffusion of the coruscations through the atmosphere caused 

 twelve accensions or meteors to appear at intervals in different 

 quarters, but most of them were to the northward ; and it also 

 had the effect of increasing the temperatue of the external air 

 near the ground half a degree between the hours of observa- 

 tion, notwithstanding the wind blew fresh from the south. This 

 was the finest aurora borealis that has been observed here during 

 the last seventeen years. In sixteen hours after its disappear- 

 ance, heavy rain and a gale of wind came on from S. E. (to 

 which quarter the coruscations mostly tended ;) the common 

 result here of the diffusion of a superabundance of electri- 

 cal fluid in the lower atmosphere. An aurora borealis of extraor- 

 dinary beauty is reported to have been seen all over Denmark in 

 the night of the 8th instant, while the moon shone in full splen- 

 dour." 



The following remarks connected with this subject, are 

 extracted from a paper by Prof. Hansteen, upon the influence 

 of distant polar lights on the magnetic needle, translated and 

 republished in the Philosophical Magazine and Annals of 

 Philosophy, for November, 1827. 



" The properties of the polar lights seem to be inexplicable, if 

 we assume that they are produced by electric currents in the atmos- 

 phere. It seems indisputable that the direction of the rays of 

 the aurora, like that of the dipping-needle, is determined by the 

 attractive and repulsive powers of the terrestrial magnetism. 

 The phenomenon of light seems to arise when the intensity of 

 the terrestrial magnetism has risen to an unusual height, and this 



