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 whom I have now and then an article of business to transact. Upon my return home, about 8$h$ 10′ P. M. looking over the houses opposite to Alban-Hall; I observed every remarkable kind of light, forming the representation of an exceeding bright crepusculum, or expanded body of vapour, which diffused itself over all the northern part of the hemisphere that presented itself to my view. This I looked upon as a prelude to an Aurora Borealis, in some form or other. But as such appearances are pretty common here, especially of late years, I then paid no great attention to it. About 8$h$ 55′, not thinking of what I had seen, I threw up my sash, and accidentally cast my eye towards the N. W. where, to my very great surprize, I discovered a luminous arch, [ XIX.] extending itself to the opposite part of the heavens, somewhat resembling an Iris, but of a bright white colour. I then went out into the street, traversed part of the town, and found the arch both in the N. W. and S. E. to be nearly terminated by the horizon; so that it seemed to be almost perfectly semicircular, and consequently in a manner to bissect the hemisphere, when completely formed. The meteor was not exactly erect, but ascended obliquely, declining a little to the N. of the zenith. It was extremely narrow, in breadth scarce exceeding two degrees. It's edges towards the S. E. were not so well defined, but somewhat jagged and unequal. From 9$h$ to 9$h$ 15′ it exhibited a most vivid resplendent whiteness, such as, I believe, was hardly ever observed before. During that term, the phænomenon seemed altogether fixed and permanent, without increase or diminution, without any apparent motion of