224 



REPOKT 1875. 



at the time when the earth encountered at that point the great meteor- 

 shower of the 6th of December in that year, observed by Brandes, Eiela's 

 comet was in the position marked C, somewhat nearer to the earth than at 

 the next occasion when a similar occurrence was observed in the year 1838. 

 The comet was in the latter year at a point marked A, about 300 millions of 



miles distant, measured along its orbit, from the earth. At the last great reap- 

 pearance of this star-shower connected with Biela's comet, on the 27th of 

 Kovember, 1872, the two bodies (which had last been observed in 1852 as 

 forming the nucleus of the comet) must have occupied a place on the elliptic 

 orbit marked B, at about 200 milhons of miles along the comet's path from 

 the place of the earth's intersection with the meteor-stream at N. It thus 

 appears that a long extended group of meteor-particles must accompany the 

 comet in its periodical revolution, preceding it to a distance of 300 millions 

 of miles in front, and following it to a length of 200 millions of miles in the 

 rear of its actual position, or occupying, if there is no reason to suppose this 

 elongated meteor-current discontinuous, fully 500 millions of miles in its 

 observed length along the comet's path. 



A similar investigation has led Prof. Kirkwood, of the Indiana State Uni- 

 versity, to a remarkable conclusion regarding the clusters of meteors included 

 in the current of the Leonids of November, that at least one other such 

 cluster besides that connected immediately with the comet exists to mark 

 the ancient disintegrations which this cometary body must have undergone. 

 The following letter in ' Nature ' of January 3rd, 1875, relates the results 

 of Prof. Kirkwood's investigation, and describes some observations of his own 

 by which they are supported. 



" The Meteors of Novemher 14. — The writer some time since called atten- 

 tion to the fact that the dates of certain meteoric showers, given by Hum- 



