SHOWER OF NOVEMBER I3-I4, 1866. 277 



9° 54*5' N., we find that the inclination of the orbit of the 

 mass of meteors to the plane of the ecliptic is 17° 59', and 

 that their orbital velocity at the time they encounter the 

 earth is 22*31 miles per second. The excess of this ve- 

 locity over that due to their distance from the sun arises, 

 in part at least, from the accelerating effect of the earth's 

 attraction. 



An attempt was made to estimate roughly the relative 

 numbers of meteors of different magnitudes, and it was 

 found that they occurred in about the following propor- 

 tions : — 



Out of every 100 meteors, 10 were above the ist mag. ; the brightest 

 of these were 2 to 3 times as bright as Sirius ; 



15 were between the ist and 2nd mag. 

 25 „ 2nd and 3rd mag. 



30 „ 3rd and 4th mag. 



15 „ 4th and 5th mag. 



5 were below the 5th mag. 



The average magnitude was 3*0. 



The trains left by many of the larger meteors had a 

 beautiful emerald green colour ; others were of an ashy grey, 

 and the remainder white. The meteors themselves were 

 mostly white or bluish white ; but many were of a fine 

 golden colour. 



In order to give some idea of the great velocity with 

 which the meteors enter the earth's atmosphere, it may be 

 remarked that it would be sufficient to carry a body through 

 the entire circuit of the earth in an interval of less than 

 ten and a half minutes . 



As I had the good fortune to witness the great meteoric 

 shower which occurred on the morning of the 13th Nov. 

 1833, I may state that the late display was far inferior to 

 it, both in the number of meteors seen and in the brilliancy 

 of the larger ones, and I am therefore inclined to think 

 that a much finer display may be expected to occur in 

 November next. At the time of the 1833 great shower I 



