1819.] Scientific Intelligence. 395 



XX. Aurora Borealis, observed by Dr. W. Burney. 



Gosport Observatory, Oct. 20, 1819. 



On the 17tli instant, at seven, p.m. a light about 30° on either 

 side of the magnetic north point appeared in the shape of a 

 luminous arch, whose apex was 18° above the horizon ; and in 

 about 20 minutes after, three beautiful perpendicular columns of 

 flame-coloured light sprang up in the N. by W. point. They 

 were at a short distance from each other, and about 16° hi°;h; 

 their tops spread out considerably in very fine curved streams, 

 and the bottom parts exhibited a dark-blue colour. While pass- 

 ing off steadily in a southern course, several shorter columns 

 appeared, and followed exactly in the same direction, the wind 

 being at that time fresh from the northward, and having some 

 influence upon their motion. 



At a quarter before eight, several other columns appeared ; 

 they also passed off slowly, and were immediately followed by a 

 small brilliant meteor. At half-past eight, two more perpendi- 

 cular columns sprang up about N.W. by N. one 4°, and the 

 other 9° long, and 2° broad : these, as well as the others, 

 passed under the northern crown, and finally disappeared at due 

 W". and were also followed by three brilliant meteors, which fell 

 almost perpendicularly. Behind the last two columns there 

 were six small tapering lights nearly equidistant, and about 

 4° or 5° above the horizon ; but which, in a higher northern 

 latitude, would have had a beautiful appearance. At a quarter 

 before nine o'clock, the last column of light appeared at W.N.W. 

 and moved off slowly in the same direction as the others ; and 

 at nine, another meteor, with a long sparkling train, fell through 

 a great space in a westerly direction. Soon after this, the lumi- 

 nous arch in the northern hemisphere entirely disappeared, and 

 some haze collected near the horizon. At nine o'clock, the 

 thermometer stood at 40°, and sunk only 1 ° during the night ; 

 but according to the nocturnal diminution of temperature in this 

 neighbourhood with a northerly wind, it should have sunk 6° 

 lower. The barometric column too, which had been rising, now 

 began to sink slowly : these circumstances, together with the 

 meteoric phenomena and dew in the night, which seldom falls 

 during a dry northerly wind, certainly indicate that the lower 

 stratum of air had received a considerable addition of electric 

 matter from the appearance of the northern lights. In 6Q hours 

 after these lights, the barometric column had sunk three-fifths 

 of an inch, when a gale of wind came on from the S. W. with 

 heavy rain; a circumstance that frequently occurs after their 

 appearance. 



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