ex Proceedings. 
be actually 2,400 miles in the rear. As a fact they rarely come 
so close. 
The grand Leonid shower of 1866 came just when astrono- 
mers were sufficiently advanced in meteoric study to avail them- 
selves of its lessons. The previous display in 1833 had suggested 
to some that meteors bore a certain resemblance to comets, but 
the full consequences were not immediately grasped. Foremost, 
perhaps, was the now obvious meaning of their radiating from 
one point. Plainly it was the result of perspective upon a 
number of bodies whose actual paths were parallel. Therefore 
‘they were moving together; that is, they were all describing the 
same orbit round the sun. This orbit was quickly calculated, 
and almost at once came the startling announcement that it was 
identical with that of a comet seen earlier in the year. 
Comets, then, and some meteors were of common origin. 
For, when once set on the right track, other meteor displays, 
notably that of August, were also found to be so connected. 
The fact was, of course, disputed, but in 1872 it was finally set 
at rest in the most convincing manner. Biela’s comet was then 
expected, the comet which astonished everyone in 1845 by 
splitting into two. Since its next return, in 1852, it had been 
lost to sight, but in 1872 the return was very favourable, as it 
was due not far away when our earth came near its orbit on 
November 27th. Astronomers searched in vain, but early that 
night there was a remarkable display of meteors of rather 
diminutive size. Calculations quickly showed that they belonged 
to the Biela system. It is now held that the head of a comet 
consists of multitudes of these meteoric particles, the light being 
partly caused by their incessant collisions. A further result is 
that many are constantly dropping behind or getting in front, 
but still follow on in the comet’s orbit. The attraction of the 
earth and other planets is another, perhaps more potent, cause. 
Thus meteors arise from the comet’s traii—an entirely distinct 
affair from the still mysterious tail. 
Whence, we may ask, do the comets come which supply our 
meteors? Casual visitors from infinity, say some. Hruptive 
matter from the sun, say others. It is possible that both these 
ways have helped in the work, but the main source is yet more 
interesting, namely, the outermost fringe of our own solar system. 
This is deduced upon two grounds. Nearly all move, as said, 
at twenty-six miles per second. Their orbits, too, are practically 
parabolic. This means that they probably are reaching the sun 
for the first time, or else move in ellipses, whose centres lie 
further away even than Neptune. Had they come from yet 
remoter stellar regions, they would have a higher velocity and 
hyperbolic orbits. 
Unless a comet passes very near us, the Harth does not 
