161 



green grass in the middle, aud is frequently seven or 

 eight yards in diameter. The other is a circle of the 

 same breadth, of very green grass, much fresher than 

 that in tiie middle. These are generally observed 

 after storms of thunder and lightning. And il is no 

 wonder, that lightning, like other fires, moves circularly, 

 and burns more at tiie extremity than in the middle- 

 The second kind of circles, without all doubt, spring 

 originally from the first : tiie grass, which was burnt up 

 by the lightning, growing afterward more fresh and 

 green* 



But of what kind was that meteor which appeared 

 March 21, 1676? Two hours after sun-set, it came 

 over the Adriatic sea, from E. N. E. to W. S.. W. and 

 crossed over all Italy, being nearly vertical to Rimini on 

 the one side, and Leghorn on the other. It was at least 

 thirty-eight miles high. In all places near its course, it 

 made a hissing noise like a sky-rocket. Having passed 

 Leghorn, it gave a sound like that of a large cannon, 

 and quickly after like a cart, running over stones. It 

 was computed to move 160 miles in a minute, .which is 

 above ten times as .swift as the diurnal motion of the 

 earth. Its smaller diameter was judged to be above half 

 a mile. !No wonder then, that so large a body, moving 

 with such incredible swiftness through the air, though so 

 much rarefied, should cause that hissing noise.. It is 

 much harder to conceive, how sucli an impetus could be 

 impressed upon it : how this impetus should be deter- 

 mined, in a direction so nearly parallel to the horizon? 

 And what sort of substance it must be, that could be so 

 impelled and igrmted at the same time ? Whatever it 

 was, it sunk, and was extinguished in the Tyrrhene sea, 

 to the W. S. W. of Leghorn, The great noi.-e was 

 heard, on its immersion into the water, the rattling 

 sound upon its quenching, 



On Thursday, March 1.9, 1719, there appeared at 

 London, about eight at night, a sudden great light, mov- 

 ing after the manner, but more slowly than a falling star,, 



