Kirkwood.] D\jZ [N oy . a , 1873. 



More observations will evidently be necessary to determine the period. 

 The preceding dates, however, may all be represented in the following 

 scheme : 



A. D. 849 to 1825 75 periods of 13 years. 



1825 to 1838 1 period of 13 " 



1838 to 1864 2 periods of 13 " 



It seems, therefore,, somewhat probable that the meteors of this group 

 complete a revolution in about 13 years. The showers of 1835-40 indi- 

 cate, moreover, that the cluster has become so much extended as to 

 occupy five years in passing the node. With a period of 13 years we find 



the Mean distance = 5.53 



Aphelion " = 10.06 



or nearly equal to the distance of Saturn. 



In the Astrono7tiische Naclirichten, No. 1632, Dr. Edmund Weiss, of 

 Vienna, called attention to the fact, that the fourth comet of I860, in its 

 ascending node, approaches very near the point passed by the earth 

 about the 3d of January. The elements of this comet according to Valz 

 are as follows : 



Perihelion Passage 1860, Sept. 28. 



Longitude of perihelion 110° 59' 



Longitude of ascending node 104° 14' 



Inclination 28° 14' 



Perihelion distance 0.9537 



Eccentricity 1.0000 



Motion Retrograde. 



The comet was discovered by Tempel, at Marseilles, on the 23d of 

 October. It was very faint, and but four observations were obtained. 

 It had an apparent diameter of from three to four minutes. Its light 

 was "not uniform, but scattered like a small cluster of very delicate 

 stars, insomuch, that the discoverer was for some time doubtful whether 

 it was really a comet." The body in this respect had a striking resem- 

 blance to that of 1866, which is associated with the meteors of November 

 14th. 



According to M. Valz the orbit of the comet of 1860 (IV) is a para- 

 bola. The* observations, however, which were very imperfect, could be 

 perhaps as well represented by elliptic elements. If it is really the 

 source of the January meteors, its periodicity must be regarded as at 

 least highly probable. It is remarkable, moreover, that on the hypothesis 

 of elliptic motion, the longitude of the comet's descending node differs 

 less than 8° from that of its aphelion. The latter point is, therefore, 

 very probably near the orbit of one of the major planets. 



If the period be thirteen years, the comet should have returned in the 

 latter part of 1873, and the maximum fall of the associated meteors 

 should occur about 1877. 



