Aurora Borealis. 177 



exhibited a well defined bow. The careful observations made at 

 Hartford by Mr. P. W. Ellsworth, when compared with my own, 

 afforded tolerably accurate data for estimating its height. From 

 these it resulted, that its perpendicular elevation above the earth was 

 160 miles. 



The aurora of the 25th of January, was the most magnificent of 

 all. It resembled that of November 17, 1835, in many particulars, 

 but its colors were brighter and more diversified, and its columns 

 arranged with more symmetry around the magnetic pole, supporting 

 a canopy of unrivalled grandeur. 



It cannot be doubted, that we are passing through one of those 

 interesting periods when the Aurora Borealis, after having been 

 scarcely visible for many years, returns in unusual frequency and 

 splendor. A number of such epochs are distinctly marked in history, 

 a full and learned account of which, as far down as the year 1731, 

 may be seen in the celebrated work of Mairan, on the Aurora Bo- 

 realis, which constitutes a separate volume of the Memoirs of the 

 Royal Academy of Sciences at Paris. Under this impression, it is 

 deemed the more important to preserve some permanent record of 

 each remarkable return of the phenomenon. The limits allowed to 

 the present article, however, will permit only a very cursory review 

 of the facts. 



The following is a synopsis of the observations made by the writer 

 of this article. 



My attention v/as first attracted to the aurora as early as 6 o'clock, 

 before the twilight was over. At this time, the northern sky exhib- 

 ited a blush not unlike that of the fairest dawn. This was skirted 

 on the east and west by ill-defined columns of crimson light, which 

 moved slowly from north to south. At 7 o'clock, these began to send 

 up streamers, all of which tended, as usual, to a common focus situa- 

 ted a few degrees south and east of the zenith. At ten minutes past 

 7 o'clock, the corona was distinctly formed, embracing the Pleiades, 

 which were nearly at its center, and seemed for a few moments to 

 control its mysterious movements. By the diurnal motion, however, 

 those stars soon moved to the westward ; but the common focus, or 

 point of concourse, of all the streamers, held a fixed position in the 

 magnetic meridian, and at or near the pole of the dipping needle, as 

 was the case in the similar exhibition of November, 1835. At three 

 different times during the evening, the corona was dispersed, and as 

 often re-formed ; but the position of its center remained nearly inva- 



Vol. XXXII.— No. 1. 23 



