VOL. XXX.J PHILOSOPHICAL TRANSACTIONS. 441 



I went to view the place where the water fell ; though I believed this inun- 

 dation might proceed from an eruption of water out of the side of the moun- 

 tain ; such being not unfrequent, where lead or coal have been dug, but neither 

 have ever been sought for here. On approaching the place, I was struck with 

 unspeakable horror, the ground was torn up to the very rock, where the water 

 fell, which was above 7 feet deep, and a deep gulph made for above half a mile, 

 and vast heaps of earth cast up on each side of it. some pieces remaining yet 

 above 20 feet over, and 6 or 7 feet thick. About 10 acres of ground were 

 destroyed by this flood. The first breach, where the water fell, is about 6o 

 feet over, and no appearance of any eruption, the ground being firm about it, 

 and no cavity appearing. The ground on each side the gulph was so shaken, 

 that large chasms appeared at above 30 feet distance, which a few days after I 

 observed the shepherds were filling up, lest their sheep should fall into them. 



An Account of the Phtenomena of a very extraordinary Aurora BorealiSy seen at 

 London on Nov. 10, 17^9? ^oth Morning and Evening. By Dr. Edmund 

 Halley, R, S. Seer. N° 363, p. lOQQ. 



On Tuesday, Nov. 10, 1719, about 5 in the morning, I perceived certain white 

 streaks in the sky, nearly perpendicular; which while I considered them, seemed 

 instantly to vanish, and soon after others came as instantaneously in their room. 

 I began to imagine that this was likely to be some part of the phsenomena of 

 the aurora borealis ; only there appeared nothing like that luminous arch which 

 we have of late so often seen in the north ; till looking up towards the zenith, I 

 perceived an entire canopy of such kind of white striae, seeming to descend 

 from a white circle of faint clouds about 7 or 8 degrees in diameter, which 

 circle sometimes would vanish on a sudden, and as suddenly be renewed. I 

 observed that the centre of this place of concourse was not precisely in the 

 zenith, but rather 14° to the south of it; which I was well enabled to estimate 

 by a star, which on each return showed itself about the centre of the circle. 

 This star is the 33d of the Great Bear in Tycho's Catalogue, whose distance 

 from the pole at this time is 52-i- degrees, and which about half an hour past 5 

 that morning passed the meridian; so that those rays centered very nearly on the 

 meridian itself It was a very entertaining sight, till such time as the day- 

 break began to obscure these lights, which were but faint, though sufficiently 

 distinguishable. None of them came lower than to about 30 or 40 degrees of 

 altitude, and seemed not to have ascended from the horizon. The sky was 

 perfectly serene and calm, which seems to be one of the concomitant circum- 

 stances attending the aurora borealis, of which this was certainly a species. For 



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