204 H. A, Newton on Shooting Stars. : 
, = 
would be not much greater than that of a body falling tothe 
earth from an infinite distance—that is, not much greater 
11 kilometers per second. So small a mean velocity is entirel 
tending much beyond these planets. i 
15. A large portion of the meteoroids must, when they meet the earth, 
have absolute velocities greater than the earth's velocity in tts orbit; 
or else, the sporadic meteors have a series of radiants at some dis — 
tance from the ecliptic, and hence come from a series of rings 
erably inclined to the earth’s orbit.—-For shooting stars cannot have 
relative motions upward from the earth’s surface when they enter” 
the atmosphere. If then the absolute velocities of the meteor 
oids were all less than those of the earth, their relative motions” 
a 
considered the disproportion between the morning and evening 
hours would be slightly diminished. But even with this allow | 
ance the increase through the night would be greater than | 
observed increase, unless one of the two suppositions abo 
given is true. se 
16. Distribution of the orbits of the meteoroids in the solar system 
—There are at least three suppositions respecting the distros : 
7 of the orbits of the meteoroids in the solar system which re 
naturally suggested. Hither of them may be considered as plaus 
ible, and one does not exclude another. 
Ist. They may form a number of rings, like the August 27 ri ‘ 
cutting or passing near the earth’s orbit at many points along 
ireuit. The sporadic shooting stars may be outliers of such ring 
2d, They may form a disk in or near the plane of the : 
of the 
8d. 
nets, eee re 
ey may be distributed at random, like the orbits ket 
ccordi or ling to the first of these suppositions there should | 
cession of radiants mocmlnoadiag to the several rings a? 
