OBSERVATIONS ON THE AURORA BOREALIS.

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5. London , September 16 th, 1838.—The Aurora Borealis, after rather a longabsence from this neighbourhood, has again made its appearance, and displayed itstransient beams, twice at least within the last week. On Sunday evening, the 16thof September, I observed an unusually strong light among the clouds in the northernparts of the heavens, from which I suspected that an Aurora had either appeared inan earlier part of the evening, or that it was about to show itself. The light soonbecame much stronger, probably from the dispersion of the clouds, which had nowmostly left the theatre of display; and the Aurora was identified by a few dim verti-cal streamers, that occasionally gleamed on the eastern side of the north point of themeridian. The general glare of light became much stronger in a very short timeafterwards; and about nine o’clock, or perhaps a little after, undulatory waves oflight rolled upwards in a very magnificent manner. At this time there did not appearany indication of the black segment which is usually seen beneath the brightest partof the Aurora; and the light was so strong, and generally diffused in the northernheavens, as to prevent ascertaining with exactness both the source of the waves andalso the highest altitude to which they ascended. They seemed to come into exist-ence at about 8° or 10° of altitude, and roll to elevations between 20° aud 60°, andsome of them might possibly ascend much higher than the latter altitude. The wavesstretched horizontally across the meridian to between 40° or 50° east and west. Theyhad very much the appearance of illuminated vaporous matter, and did not undulateat a very brisk rate. They were densest at their commencement, and became moreand more attenuated as they ascended the heavens, and vanished at their terminalmargins in the softest diffusions of pale expiring auroral light. The waves weresucceeded by a few feeble streamers of considerable length, but without much motion,and mostly displayed on the western side of the meridian. It is very probable that,had there not been such a general glare of light in the northern part of the heavens,many more streamers would have been seen.

The sky became quite clear of clouds a short time after the disappearance of thewaves, and the central part of the Aurora had obviously taken a position nearly in themagnetic meridian—although, previously to the appearance of the waves, the regionof strongest light was as obviously on 'the eastern side of the tfue meridian.

W. S.

6. London , September 3rd, 1839.—A very singular Aurora Borealis appeared atLondon and its vicinity last night. It first made its appearance about a quarterbefore nine o’clock, and continued nearly the whole of the night. I Avas walking fromBrixton to Peckham, between nine and ten, and kept the Aurora in view the wholeof the time. I first saw it when passing Brixton Church, then about nine o’clock ;its appearance was that of a yellowish light, at a small altitude above the northern

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