THE NOVEMBER METEORS. 165 



1. That meteors and meteoric rings are the debris of ancient 

 but now disintegrated comets, whose materials have become 

 distributed around their orbits. 



2. That the separation of Biela's comet as it approached the 

 sun in December, 1845, was but one in a series of similar 

 processes, which would probably continue until the individual 

 fragments would become invisible. 



3. That certain luminous meteors have entered the solar 

 system from interstellar space. 



4. That the orbits of some meteors and periodic comets have 

 been transformed into ellipses by planetary perturbation. 



5. That numerous facts, some observed in ancient and some 

 in modern times, have been decidedly indicative of cometary 

 disintegration. 



The Planet Uranus is credited by competent mathematicians 

 with having first drawn the group of Leonids into our system, 

 and that by virtue of its attraction its parabolic orbit was 

 changed into an elliptic one, with the sun in one of its foci ; 

 hence it became a member of the sun's family. The attraction 

 of Jupiter and Saturn has also something to do with the present 

 form and plane of its orbit, and with its intersection with the 

 orbit of the earth. 



There are several questions of interest to be settled by careful 

 observation, such as the duration of the shower. Perhaps 

 November yth is not too early, and certainly November 2oth is 

 not too late ; but great care must be taken that those seen earlier 

 or later than the above dates are true Leonids. Then there is 

 the exact position of the radiant point, by no means yet satis- 

 factorily fixed. Then there is the width of its area. Then there 

 is the mobility of the radiant, still a moot question among experts. 

 A few words about the radiant. Professor Adams fixed it at 

 149 12' R.A. and + 23 i' in Dec. This is generally accepted, 

 though only derived from 7 values. Denning' s radiant, derived 

 from 70 values, is nearly the same. 



Visible aspects of the Leonids as given by accredited 

 observers : 



