226 REPORT — 1875. 



h "h 



From 10 to 11 20 meteors, 



„ 11 » 12 35 ,, 



» 12 „ 1 40 „ 



„ 1 „ 2 52 „ 



jj 2 „ 3 75 „ 



„ 3 „ 4 59 „ 



Total 281 „ 



" ' When the meteors Trere most numerous, near 3 o'clock, the common 

 point of divergence in Leo was distinctly observed.' 



" I may here add, although the fact is not stated in my memoranda, that 

 the conformable meteors, or a majority of them, were seen near the radiant, 

 and that they were generally smaller and had shorter tracks than the No- 

 vember meteors observed between 1865 and 1870. The number seen was 

 too small to be called a shower; at the maximum, however, the fall per hour 

 was nearly double that of ordinary nights. In short, I have no doubt that 

 they were Leonids, and think it highly probable that they were derived from 

 a distinct cluster which passed its perihelion in 1787 and 1820. We have 

 therefore nine recorded meteor-faUs which indicate the existence of a second 

 cluster of Leonids, viz. those of a.d, 288, 855, 856, 1787, 1818, 1820, 1822, 

 1823, and 1852. The showers of 855 and 856 may be somewhat doubtful. 

 If derived from the same meteor-cloud as the others, the dates would indicate 

 considerable perturbations either by Uranus or the earth. The displays 

 have been much less conspicuous than those of the major group, and hence 

 the phenomena have been less frequently observed. The period is about 

 33-33 years, while that of the other swarm, according to Newton, is 33-25 

 years. Since their separation, therefore, the latter has gained nearly two- 

 thirds of a revolution in their relative motion. The estimates which have 

 been made in regard to the recent entrance of the cluster into the planetary 

 system must consequently be rejected. — Daniel Kirkwoob." 



" Bloomington, Indiana, U. S. A., 

 April 20th, 1875." 



Lists of Meteor and Meteor-shower observations and of Cometary Radiant- 

 points. — In the above-quoted publication (of May 1874) of the Italian Spec- 

 troscopic Society, Prof. Schiaparelli reviews at some length the catalogue of 

 observations and of meteor radiant-points by Capt. Tupman, deriving from 

 them chiefly average results relating to the apparent length and to the time 

 of flight of the recorded meteor-tracks. The annexed diagram shows ap- 

 proximately the numbers of meteors in the list of different lengths and 

 durations of flight proceeding by intervals of 1° up to 30° in length of path, 

 and of one tenth of a second up to two seconds in the time of flight. The 

 curve of relative frequency in length of path is drawn from the actual 

 numbers of the observations, including 1951 recorded tracks ; and the most 

 frequent leugths of path recorded among them are between 7° and 10° ; the 

 average length of path derived from the whole series of observations in the 

 list is ll°-0, falling a little short of the mean apparent length of course of 

 meteor-tracks (13°-9) assigned by Coulvier Gravier. 



The curve of frequency of the different times of flight is a reduced one 

 from the total number of 1613 observations, allowing for the rough estima- 

 tions at 0^-5, 1'-O, 1^-5, and 2^-0 preponderating greatly among the other more 



