Evening star., 1896-12-12

>N&N' edTln IN pulk, OF,
more usually. hundreds or even millions of
times greater. There is, however, Que
Class Of objects. strictly belonging to the
province of astronomy, which have no
pretensicrs to consideration on the ground
Of their bulk. The objects of which I speak
are. in fact, rot as large even the small
est of moons or the most telescope OF plan
cts. They are not even so big as the noun
tains on the earth; the majority of them
are indeed little pieces of matter no larger
than the pebbles on garden walk. l dare
say that many of them are not greater
than the grains Of sand on the seashore.
We denote them by the word meteors.
These little objects must. however be
regarded bodies which come within the
province of the astronomer, for they have
an existence quite independent of our earth
and move freely through space. in SO far
at least as that part of their career is con-
cerned which precedes the supreme occa-
sion on which, once for ali, they make
their appearance to us
The most remarkable feattre of the me-
teor is the speed at which it travels.
Though often not SO large as a rife bullet,
a meteor urges its way at a pace far in
excess of that with which any rifle bullet
mas ever been driven, or, We may indeed
say, far in excess of that with which any
rifle bullet ever could be driven.
We find that meteors are generally ami
mated with speeds far in excess of these
possessed by any rife bullet. For our pres
ent purpose there is no occasion to inquire
as to the manner in which such terrific
velocities have been originally impaired.
All that we have now to consider is the
fact these little objects when moving II,
free space are certainly hurrying along
with velocities ten times, twenty times
fifty times. or sometimes even 100 times as
swift as the swiftest rifle bullet that ever
was fired.
Round the Globe In Ten Minutes.
II a meteor were to fly round the equa-
tor while preserving all the time its char
acterfstic speed, 1t would take no more
than two or three minutes to cross each of
the continents and each of the oceans
which lay in its way; ard, In fact the
whole journey round the globe would be
accomplished within ten minutes. Animat-
ed by such speed body would pass from
Liverpool to New York in a minute, or 1t
would travel all the way from the earth to
the moon in less than an hour and a half.
meteor urging its course with this STU
pendous rapi1ity may pass near the earth,
say at distance of a thousand miles or
so. 1t then pursues its way and entirely
escapes our attention. No doubt the at
traction of the great mass of the earth
VIII. to certain extent pull the object and
compel 1t to swerve from the direction Ii
mas been following. but provided it gets
clear OF the atmosphere which so complete
ly invests the earth, the meteor will be un-
injured and will not lose its velocity
Doubtless every day, ray, every hour and
every minute. unseen meteors are passing
by the earth. narrowly escaping a fall
which would forever terminate their wan
deringS.
Suppose, however, the direction of the
motion of a meteor be such that il enters
our earth's atmosphere. Immediately its
terrific motion is checked. 1t might almost
be said to be checked with nearly the same
emphasis as the speed of an ordinary rifle
bullet would be checked if it were fired into
hay stack. The speed which the meteor
possesses before 1t has struck :ato our at
mosphere cannot possibly be maintained
afterWard. The resistance of the air will
not permit it. But the efforts of the celes-
tial Wanderer TO continue its astonishing
movements after it has taken the plunge
lead TO consequences which, though fatal to
the meteor, are OF the highest interest.
Result of Friction.
Every one knows that the friction of two
bodies rubbing against each other is fire.
quently accompanied by the production of
heat A neglected axle-box in a carriage
in rapid motion has occasionally been
known to set a railway train on fire In
this case the axle, from not being properly
supplied with grease, has become hot from
friction, and as the friction still continued
the heat gradually rose until temperature
sufficient to produce ignition had been gen
Grated. AS the flying meteor dashes
through the air, the air rubs on the surface
of the little missile. 1t can be shown by
experiment that the friction of the air
against a body hurrying rapidly through it
produces heat.
1t is true that we are not actually able to
try this experiment with a body moving so
quickly as a meteor, but we can experiment
up to certain point, and then calcula ton
will take up the reasoning, and conduct to