AEROLITES. 117 



of prodigious breadth. In this group the orbit of the 

 outermost, that is the seventh, satellite, has a diameter so 

 considerable, that the earth, in her course round the sun, 

 requires three days to pass through an equal space. If in 

 one of the continuous rings, which we have imagined as formed 

 by the paths of the periodical streams, we suppose the dis- 

 tribution of the asteroids to be such that there are only a few 

 groups so closely congregated as to occasion the appearance 

 of showers, we may conceive how such brilliant phenomena 

 as those of November 1799 and 1833 may be of exceedingly 

 rare occurrence. The highly ingenious Olbers was inclined 

 to think, that the next return of the great phsenomenon of 

 fire-balls and shooting stars falling like flakes of snow, 

 would be witnessed from the 12th to the 14th of November, 

 1867. 



Sometimes the stream of the November asteroids has 

 been visible over a small portion only of the earth's surface : 

 for example, in the year 1837, it was seen with great mag- 

 nificence as a meteoric shower in England, whilst, on the 

 same night, which was uninterruptedly clear, a very atten- 

 tive and practised observer at Braunsberg, in Prussia, saw 

 only a few sporadic shooting stars between 7 P.M. and sun- 

 rise the following morning. Hence, Bessel inferred ( 76 ) that 

 a small group of the great ring occupied by these bodies 

 approached the earth in England only, while the countries 

 to the eastward passed through a part of the meteoric ring 

 which was comparatively void. Should increased proba- 

 bility be given to the supposition of a regular progression 

 of the line of nodes, or of its oscillation in consequence of 

 perturbations, the discovery of older observations of these 

 phenomena will acquire a special interest. The Chinese 



