VOL. XXX.} PHILOSOPHICAL TRANSACTIONS. 2QI 



Again, on the 30th of March following, there was another aurora borealis. 

 I saw it not till past Q : it was dim then, and its highest part covered the lowest 

 star in Cassiopeia's chair. It did not seem due north, but one point to the 

 west. About 10 it shot out very bright rays, high, and tending somewhat 

 towards one another. Near 1 1 o'clock, there was, besides the northern bright- 

 ness, a long streak, not very broad, extended east and west ; which beginning 

 in the Serpent's head, near Hercules' club, and covering Arcturus, proceeded 

 near Berenice's hair, and so went over Cor Leonis, and thence to the Canicula, 

 and ended a little beyond that star. It shone very bright at first, but faded 

 away in about 8 or Q minutes. If it had motion (which I am not sure of) it 

 was southward. I waited for the next fit of brightness of the aurora ; and in 

 about 7 minutes, the eastern part of the streak, viz. from the Serpent's head 

 to near Berenice's hair, became visible again, though dim, and was quite effaced 

 in 4 or 5 minutes more: and I did not yet perceive any change of its place. 



j4n Account of the Aurora Borealis, seen at London, the 30th of March last. 

 By Martin Folkes* Esq. R. S. Soc. N° 352, p. 5&G. 



Being in the street, (of London) between 8 and g o'clock on March 30, 

 I perceived a light over the houses to the northwards, little inferior to that of 

 the full moon when she first rises. On this I made all the haste I could into 

 the fields, where I was for some time agreeably entertained with the sight of 

 an aurora borealis, attended with most of the phaenomena that have been 

 described in that very remarkable one of the 6th of March, 17 ] 5-6. 



The whole northern part of the horizon was in the same manner covered 

 with somewhat resembling a very black cloud, from behind which there issued 

 a considerable light, whose lower part was pretty well defined by the common 

 edge of the cloud, but the upper died away more gradually. This upper limb 

 of the light resembled the arc of a circle, whose highest point, between 9 and 

 10 o'clock, when the meteor was most considerable, was elevated about 12 

 degrees, and bore, as I imagined, about 20 degrees westward of the due north. 

 It touched the horizon in the west at the distance of about 6b or 70 degrees 



* Mr, Folkes was born at Westminster about the year 169O. At tlie early age of 24 he was 

 elected a fellow of the Royal Society., to which he proved an active and useftil member, and had 

 the honour afterwards to be chosen president of the Society, an honour which he enjoyed many 

 years. Mr. Folkes wrote several papers in the Transactions, in the different Volumes, from the 

 30th to the 46th. Besides which, he was author of a treatise, in 4to. on the English coins, 

 from the Conquest down to his own time. He died at London in 1754, By his will he be- 

 queathed to the R. S. 2001. and his large cornelian seal ring, on which are engraven the arms 

 of the Society, for the perpetual use of the president. 



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