METEORS. 337 



in the same direction, at a small distance from each other, 

 and very little behind the principal body, the size of which 

 was gradually reduced after this division. In this form 

 the meteor moved as far as the southeast by east point, 

 where the light decreasing rather abruptly, the whole 

 disappeared. 



' During the phenomenon no noise was heard by any 

 of our company excepting one person, who imagined to 

 have heard a crackling noise, something like that which 

 is produced by small wood when burning. But about ten 

 minutes after the disappearance of the meteor, and when 

 we were just going to retire from the terrace, we heard a 

 rumbling noise as if it were of thunder at a great distance, 

 which in all probability was the report of the meteor's 

 explosion ; and it may be naturally imagined that this 

 explosion happened when the meteor parted inlo small 

 bodies, viz. at about the middle of its track.' From the 

 interval between the apparent explosion, and the time the 

 report was heard, the distance of the meteor from the 

 spectators may be easily computed. Sound is ascertained 

 to travel at the rate of 1 150 feet per second.* About ten 

 minutes elapsed after the disappearance of the meteor 

 before the report was heard. From these particulars the 

 following calculations have been made with mathematical 

 accuracy respecting the distance, altitude, course, and 

 diameter of this meteor. It is, however, obvious, that if 

 the noise heard was not that of the meteor's explosion, or, 

 if the meteor did not explode when it appeared to, the 

 following results must be considered as altogether useless. 



D:?Unce of the Meteor from Windsor castle, . 130 miles. 



Length of path described in the heavens, . . 550 miles. 

 Diameter of the luminous body when it came out of 



the clouds, 1070 yards. 



Its height above the surface of the earth, . . 56^ miles, 



* The rapidity with which sound travels is easily ascertained by 

 experiment. When a cannon is fired, a spectator at a distance, sees 

 the flash some time before he hears the report. Then by measuring 

 the distance between the c:u-,non and himself, and observing the time 

 which elapsed between the flash and the report, he learns bow Jonsf 

 it took the sound to travel that distance. In the same manner you 

 may learn the distance of thunder, by observing the interval be- 

 tween the Hash a-.id the report. 



