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POPULAR SCIENCE MONTHLY 



and character, but I made a series of eight sketches at intervals of 

 about twent}' minutes apart, which illustrate the most striking changes. 

 The second form was a homogeneous arc with a fragment of a second 

 arc under it. This hung for some time, with a steady nebulous glow 

 between it and the one pi-evious, as ^yell as between the intervening 

 periods of all. The following typical forms then were rapid and almost 

 imperceptible gradations. The third sketch represents the same posi- 

 tion on the heavens; but under it are portions of two other arcs and a 

 suggestion of a luminous horizontal line. At times a wave of rays, 

 converging to the pole of the circle described, ran over the main arc. 

 In the fourth sketch there are two arcs and a portion of a third which 

 were seen persistently in all the exhibits to be present. In the fifth 

 there is a second arc crossing the first. This was suggested by the 



March 26. Early Display. This was Followed by IDarting Rays and Wavy Ribbons 



WHICH Ended in a Brilliant Arc with Moving Ray's Drawn Over it Convkrging 



TO A Common Center, as Shown Below. 





March liiJ. Later. 



third, and it reappeared in the seventh. The sixth form was an arc 

 with three ribbons of luminous beams waving from side to side. The 

 exhibit ended with a plain arc aglow with a steady light. 



For a week following we had faint auroral displays every night, 

 but we seldom saw a brilliant or extensive exhibit. The usual form it 

 took at this time was that of a fragment of one or several arches. On 

 the night of the 26th we saw the usual auroral patches in the southeast 

 which we had seen so often before. These disappeared entirely at ten 

 o'clock, but reappeared shortly after in a manner and vividness worthy 

 of note. There was a steady luminous bow somewhat brighter than 

 the Magellanic clouds, and over this there were bunches of brighter 

 rays with a rapid motion from east to west. These rays centered to 

 a point below the horizon. Under this main arc there was from time 

 to time a suggestion of a second and also a continuation of the same 



