VOL. XXIX.] FHILOSOPHICAL TRANSACTIONS. 227 



within a short way of the horizon. There likewise appeared a body of light, 

 N. N. E. of us, and continued as light almost as day, till after 12 o'clock. It 

 appeared at a good distance from us, and darkened on a sudden." Hence it 

 would seem, that the vapour which caused this appearance, arose indifferently 

 out of the ocean, as well as from the land ; by which we may conclude the 

 great subtlety of the matter thereof, since it could permeate so great a quan- 

 tity of water, and yet retain its velocity; which is a circumstance deserving the 

 further consideration of the curious. 



But since this, most of the same phaenomena have been repeated three 

 several nights successively, viz. on the last of March, and 1st and 2d of April. 

 The best and fullest description of the first two, is given by Dr. Brook Taylor, 

 LL. D. and secretary to the Royal Society, dated April 2, from Cotterstock, 

 near Oundle in Northamptonshire, who thus describes them : — " On Saturday 

 night last, and last night, I saw appearances of the same kind with those of 

 March 6, but not to compare for extent and strength to the other. They 

 both began soon after sun-set, and continued till after ] 2, but how much longer 

 I cannot tell. They were both about 10 or 15 degrees to the westward of the 

 north, and took up about 80 degrees of the horizon; and the aurora rose 

 about 30^ high, with a dark bottom, like what was seen in the first ; and from 

 whence there sprung out several bodies of light, which immediately ran into 

 streams, ascending about 30, or at most 40" high. There was no flashing 

 nor waving light, but in all other respects these lights were of the same kind 

 with what we saw at London. Indeed in that last night, there was one phe- 

 nomenon like the flashing light, for a body of light about 15 or 20 degrees 

 long, parallel to the horizon, rose till it came about 6 degrees above the 

 black basis, and then sent up two strong streams of light about 40° high, which 

 at top dashed against one another, and disappeared." 



At London, the first night, March 31, it did not begin to radiate, till to- 

 wards midnight, and was seen only by few curious persons; the beams not 

 rising very high, and scarcely appearing over the houses, were but little 

 noticed : but by the accounts of those that saw it, it was much more consider- 

 able than the next night following Easter-day, for it then sent out but few 

 and very short beams, mostly terminating in a sharp point, and presently 

 disappearing. Only beginning to stream as soon as it became dusky, it 

 was very observable that those rays which rose out of the west end of the 

 luminous arc, next the sun, were enlightened by its beams, and showed 

 themselves much brighter than those which sprung up under the pole, or 

 to the eastward of it. And after 9, till midnight, no more beams arose; 



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