A RECENT STAR SHOWER. 193 



round the sun in about 6| years, and on a path 

 approaching very closely indeed to the earth's. Indeed, 

 great alarm was experienced when the return of the 

 comet was expected in 1832 ; for it was shown by the 

 calculations of astronomers that the head of the comet 

 would actually envelope the part of the earth's orbit 

 which she crosses on November 30. This, in fact, 

 happened ; but since it happened (as predicted) on the 

 29th of October, 1832, when the earth was a month's 

 journey from that part of her orbit, of course there 

 was no collision. Twice more the comet circled on its 

 wide path, extending far beyond the orbit of Jupiter ; 

 and again in 1846 it was in our neighbourhood, and 

 under the careful telescopic scrutiny of astronomers. 

 It was then that, almost under their eyes, the comet 

 behaved in a most remarkable manner. Up to the 

 13th of January it had presented its usual aspect, 

 a round hairy-looking head enclosing a brighter nu- 

 cleus, and a narrow, straight, and rather short tail ; 

 but on that day, to the astonishment of the telescopist 

 who first recognised the change, the comet was found 

 to be double. There, in the place of the single comet 

 of the day before, were ' two distinct comets,' says Sir 

 John Herschel, c each with a head, coma, and a little 

 nucleus of its own ; ' and each with a tail also, if the 

 pictures by the German observers are to be trusted. 

 < What domestic trouble caused the secession,' proceeds 

 Herschel, ' it is impossible to conjecture, but the two 

 receded farther and farther from each other up to a 

 certain moderate distance, with some degree of mutual 



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