150 Meteoric Astronomy. [April, 
the velocity of Uranus in his orbit in the proportion 
of about 7 to 5. So that, roughly, their velocity at that 
distance has been reduced in the proportion of more than 
21 to 5, or by 7-gths of its original value. This is a reduc- 
tion of about 43 miles per second. Now Uranus could 
barely impart this velocity to a body approaching him from 
an infinite distance under his sole influence, and coming as 
near to him as the nearest of his satellites; but he could 
not impart so much additional velocity to a body approach- 
ing him (more rapidly of course) under solar influence. Now 
the velocity a body can impart it can also take away. Hence 
the retarding action of Uranus could under no circum- 
stances account for the velocity of about 4} miles per 
second, by which the motion of Tempel’s comet must have 
been reduced, unless that comet passed closer to Uranus 
than his nearest satellite. Indeed, the maximum velocity 
which Uranus could impart to a body actually reaching his 
surface (and exposed to his sole influence in approaching 
from infinity) amounts only to 13°7 miles per second. Now 
the distance of Uranus’s nearest satellite from the planet’s 
surface is but about 84,ooomiles, and Uranus traverses such 
a distance in less than five hours. So that the first and last 
meteors so influenced by Uranus as to be forced to part with 
a velocity of 43 miles per second out of their actual 
velocity of about 6 miles per second, were assuredly not 
separated by a distance equal to a five hours’ voyage, or in 
miles (at 6 miles per second) by so much as 108,000 miles. 
We may, indeed, safely infer that the actual distance was 
much less than this. For though all the meteors along a 
distance of 108,000 miles might have their velocity suffici- 
ently reduced, yet in this case some of the meteors would 
have their velocity too much reduced, and would thenceforth 
pursue orbits differing very markedly from the orbits 
traversed by the remaining members of the system. 
It follows, not merely as a probable inference, but I think 
as a demonstrated conclusion, that if the November meteors 
came originally into our system as a comet travelling sun- 
ward from infinity, then either that comet was very com- 
pact, or else Uranus captured only a small portion of the 
comet, the remaining portions moving thenceforth on orbits 
wholly different from the path of the November meteors. 
There is no escape from this conclusion; for no other 
planet than Uranus can have brought about the subjection 
of this comet to solar rule. 
One is almost led to doubt the extra-planetary origin of 
the November meteor system altogether, and to entertain 
