422 Description of the Aurora Borealis 



XII. In a succeeding paper, the author may possibly 

 feubmit to the consideration of his reader, the particular and 

 novel hypotheses which he has allowed himself to form, as 

 to the substance, causes, and effects of the Aurora ; hypotheses 

 partly dependent upon those facts in its natural history, 

 which, above, have been almost the exclusive objects of atten- 

 tion. At present, the leading particulars of the natural history 

 of the phenomenon, which it has been attempted either to 

 bring or to fix in view, are these : 



1. That the Aurora is a phenomenon observed both in the 

 Northern and Southern Hemispheres. 



2. That, in either hemisphere, it is observed in the general 

 direction of the corresponding pole of the earth. 



3. That, in the Northern Hemisphere, on the shores of the 

 Icy Sea, or at the furthest distance north, its situation is still 

 observed to be the northward. 



4. That, in the Southern Hemisphere, it has been observed to 

 the east of the South Pole, and in the Northern, to the east 

 and west of the North Pole. 



5. That, upon the late occasion, the place of its columns, 

 during the exhibition, was observed to change from the west 

 of north to the east of north ; but, so as always to have the 

 north for the apparent centre of its strength. 



6. That, in the Arctic regions, the appearance of the Aurora 

 is said to be usually followed by clear and calm weather. 



7. That the appearance of the Aurora Borealis is no wise 

 peculiar to the winter solstice, but has been observed in each of 

 the eight months of September, October, November, December, 

 January, February, March, and April, and may be regarded, 

 therefore, as coincident with the Arctic winter ; and that the 

 appearance of an Aurora in the Southern Hemisphere, in the 

 month of February, or beginning of the Antarctic winter, as ob- 

 served during the voyage of Captain Cook, in the year 1773, is 



his theory, according to wliich the physical use, or final cause, of the existence 

 of the Ocean has never previously been understood. His theory affects the 

 question of the North-west Passage, whicli latter object he suspects to have 

 never yet been pursued in the true direction; even the discoveries of Captain 

 Parry appearing to him to have fallen short of ascertaining the communication 

 ■with the Polar Sea by the channel of Davis's Strait. — Some introductory ob- 

 servations upon this subject have been already made in an article in the New 

 Monthly Magazine for October, 1826, (vol. xvii. p. 371.) 



