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 of the whole, and indeed almost without the least external variation. An internal undulating motion of the particles constituting the white luminous matter of the arch was nevertheless discernible, from the first to the last moment of it's existence. No stars were visible through the vapour itself, but two or three appeared at a small distance from it. These, however, were much obscured by the interposition of some thin whitish clouds, with which that part of the atmosphere was at this time covered. Not the faintest traces of a proper Aurora Borealis, either before the first appearance, during the continuance, or after the extinction of the meteor, were to be seen. Several young people were viewing it, when I went into the street; who seemed, according to custom, not a little alarmed at so unusual a sight. One of them told me, that the arch began to be formed about a quarter before nine. In other parts of the city this wonderful phænomenon was likewise observed, both by townsmen and members of the University, not without some degree of astonishment and surprize. A little past nine o'clock the extremities of the arch grew faint, as did soon after the whole body of the luminous vapour itself. About 9$h$ 20′ the summit, or highest part, of the arch, a few degrees to the N. of the zenith, only remained; which continued gradually decreasing 'till 9$h$ 27′, when the whole totally disappeared.

With regard to the weather, the morning of the 23d was dark and lowring; but the remainder of the day, from 10$h$ 45′ A. M. to sun-set, was bright and clear, though cold out of the sun. The wind 'till six P. M. was northerly, and blew pretty fresh, but