^99 -description' of- the Aurora Borealis,^ 



lically nor obliquely, according to the direction of each column, 

 and within the limits of its sides. He confesses, also, that h^ 

 did take notice of the pale, but bright violet-coloured column, 

 tlistinguished also by its breadth and height, and situated to 

 the west of north ; but which column, he is surely right in 

 adding, ultimately moved, with those next to it, toward the 

 north. He distinctly and pointedly observed, at the same 

 time, that the columns which stood due north were always 

 white, and that the colours of the other columns appeared to 

 strengthen in proportion as they were distant from the due 

 north, either west or east ; and he came to a fixed conclusion, 

 ^vhile the phenomenon was under his eye, that, to his judg- 

 raent at least, the strength of the fire, so to say, was in. that 

 point of the horizon which lay due north ; and that there wa^ 

 a diminished brightness, with a proportionable increase of 

 colour, : tQ the right and left. 



3. As to the separate movements of the columns, these, in 

 the first place, were quick, and forced upon the eye, while the 

 movement which gradually deployed or advanced the .right 

 wing of the celestial arm, and gradually contracted or with- 

 drew the left, was slow, and perceived only by its results ; and, 

 in the second place, while these Jatter were parallel to4h^ 

 horizon, the former were either vertical, or in the oblique or 

 curved direction of the bodies of the columns. But this 

 motion consisted either in vibration, or in irregular but altera . 

 nate projections and contractions ; and the motion of each 

 column, as has been said, was independent on that of others. 

 Harely. two adjoining columns were in motion at the same 

 time. Almost always the moving column or columns were 

 seen to start from the midst of others, which, for the time^ 

 Vf^re quiescent, but which had had their turn before, aiyl 

 would presently have it again. What eminently struck the 

 writer, however, was the internal motion of that to which he 

 .cannot allow himself to give another name than that of the ap- 

 parent luminous material of the columns. It seemed to him as 

 if the volume of each column or coruscation was itself com- 

 posed of parallel lines of luminous matter, arranged in the 

 direction of the column, and every one of which was separately 

 the subject of movements similar to those^ of the entire 



