en, owing to
its unfavourable situation with regard to the earth. No trace of Biela's
comet was seen in 1865-66, when its return was also due, nor has it ever
been seen since. It therefore appears that in the autumn of 1872 the
time had arrived for the return of Biela's comet, and thus the
occurrence of the great shower of the Andromedes took place about the
time when Biela's comet was actually due. The inference is irresistible
that the shooting stars, if not actually a part of the comet itself, are
at all events most intimately connected therewith. This shower is also
memorable for the telegram sent from Professor Klinkerfues to Mr. Pogson
at Madras. The telegram ran as follows:--"Biela touched earth on 27th.
Search near Theta Centauri." Pogson did search and did find a comet,
but, unfortunately, owing to bad weather he only secured observations of
it on two nights. As we require three observations to determine the
orbit of a planet or comet, it is not possible to compute the orbit of
Pogson's, but it seems almost certain that the latter cannot be
identical with either of the two components of Biela's comet. It is,
however, likely that it really was a comet moving along the same track
as Biela and the meteors.

Another display of the Biela meteors took place in 1885, just giving
time for two complete revolutions of the swarm since 1872. The display
on the 27th November, 1885, was magnificent; Professor Newton estimated
that at the time of maximum the meteors came on at the rate of 75,000
per hour. In 1892 the comet ought again to have returned to perihelion,
but in that year no meteors were seen on the 27th November, while many
were seen on the 23rd from the same radiant. The change in the point of
intersection between the orbit of the meteors and the orbit of the
earth indicated by this difference of four days was found by Bredichin
to be due to the perturbing action of Jupiter on the motion of the
swarm.

It is a noticeable circumstance that the great meteoric showers seem
never yet to have projected a missile which has reached the earth's
surface. Out of the myriads of Leonids, of Perseids, or of Andromedes,
not one particle has ever been seized and identified.[35] Those bodies
which fall from the sky to the earth, and which we call meteorites, do
not seem to come from the great showers, so far as we know. They may,
indeed, have quite a different origin from that of the periodic meteors.

It is somewhat curious