Chap. 12.] eb/eruedin 1783. 491 



tenfely bright bluifh flame, which is peculiar to fnch 

 meteors. It left behind it a dufky red ftreak of fire, 

 and, except this, had no tail, but was nearly globular. 

 After moving not lefs than ten degrees in this bright 

 ftate, it became fuddenly extinct without any explofion. 

 The height of 4he meteor muft have been between 

 forty and fifty miles ; and its duration was not more 

 than three feconds. 



The Doctor is of opinion, that the general caufe of 

 thefe phenomena is electricity, which opinion he 

 grounds upon the following circumftances : ill, The 

 velocity of thefe meteors, in which they correlpond 

 with no other body in nature but the electrical fluid. 

 2dly, The electrical phenomt-na attending meteors, 

 the lambent flames, and the fparks proceeding from 

 them, which have fometimes damaged fhips and houfes 

 in the manner of lightning, and, added to thefe, the 

 hi/Ting found, refembling that of electricity pafllng 

 from a conductor. As a third argument in favour of 

 this hypothefis, the Doctor remarks the connection of 

 meteors with the northern lights. Inftances are re- 

 corded, where northern lights have been feen to join, 

 and form luminous balls, darting about with great 

 velocity, and even leaving a train like fire-balls. The 

 aurora borealis appears to occupy as high, if not a 

 higher, region above the furface of the earth, as may 

 be concluded from the very diftant countries to which 

 it has been vifible at the fame time. 4thly, The moft 

 remarkable analogy, the Doctor thinks, is the courfe 

 of at leaft all the larger meteors, which feems to be 

 conftantly from or towards the north or north-weft 

 quarter of the heavens. Of above forty different fire- 

 balls described in the Philofophical Tran factions, twenty 

 are fo defcribed, that it is certain their courfe was in 

 that direction j only three or four feem to have moved 

 the contrary way ; and with refpect to the remainder, 



it 



