Harrisburg telegraph. [volume] (Harrisburg, Pa.) 1879-1948, 1919-02-27
Did the Earth Give
Birth to Meteorites :?
BY Garrett p. servlss


= for instance, volcanic force or
other forces of which we know ?
Who knows but what the meteorites
that we see in the museums of nat
ural history may have been thrown
from our own earth, returning from
their flight to our earth again?-
c. III. +. Loppentein."
The idea that meteorites are an
cient children of earth, gathered
again, like Dc Quincey's revolted
Tartars, from their wanderings in
the wilderness of space INTO the
fold of their forgiving shepherd" is
an old and picturesque one, which
has been debated many times with
out a final decision.
1t is not by any means inconceiv-
able that forces could be developed
in the crust of the earth similar 10
those that produce volcanic eXplo-
sions, that would hurl forth matter
with a velocity sufficient to free it
from the control of gravity, where
upon it would fall into a more or
less elongated orbit around the sun,
crossing the earth's orbit, and
through the effects of perturbations
might eventually be brought back to
the earth's surface.
a simple calculation based on
known physical laws tells us that,
neglecting the resistance of the at
mosphere, any body or particle shot
radially away from the earth at a
velocity little less than seven miles
or say, $4,000 feet, per second,
gravity and would become an indie
M lNat. Of HA al
tenn.
1t is possible that the volcanic
energies of the earth may in long
past time have been sufficient to
produce a velocity of that order. In
recent times great volcanic explo-
sions have thrown dust to height of
as much as twenty miles.
Now, neglecting the atmospheric
resistance, the velocity with which
a body would have to start in order
to ascend twenty miles against the
pull of gravity would be about o.
900 feet per second, which is not
much more than one-fourteenth of
the velocity needed to set it free.
With higher velocities it would go
farther, but in order to send it far
enough to prevent it from falling
back again in a short time it would
be necessary to approximate the
critical velocity of 5000 feet. For
instance, although q velocity of o.
coo feet per second would send the
projectile twenty miles high, ii
would require over $4,000 feet per
second 10 send it 24O,000miles Gas
far away as the moon), and in that
case it would return in about ten
days after its departure.
.r F..Y
supposing meteorites to have orig
mated in volcanoes is the fact that
they bear much resemblance, in
composition and physical state, to
minerals known to have been eject
ed from volcanoes. Another signifl-
cant fact is that, while they consist
of many substances and chemical
elements familiar to us as constitu-
ents of the earth's crust Cat least
thirty have been identifled), they
contain nothing not already known
on the earth; that is, no strange sub
stance or elements.
Some of them do, however, show
peculiarities of structure and crys-
talliZation not found in substances
of known terrestrial origin. Many of
them also contain remarkably large
quantities of occluded (shut in or
absorbed) gases. About 3 or 4 per
cent of the mcteorites THAT fall on
the earth consist OF pure iron, usu-
ally alloyed with a little nickel; the
others are composed of stony mat
ter, usually containing a little iron
or some compounds of iron.
Mr.. Harrington, the greatest liv-
ing authority on mcteorites, finds
evidence that some of the bodies
have been broken up and recement-
ed, while others show effects appar-
emily due to what geologists call
faulting, where rock stratum has
been fractured and one surface has
slid over another, and still others
contain veins in which foreign ma
terial has been deposited
1t is unnecessary to point out how
strkingly all these things accord
with the hypothesis that the meteor
ties originated in some great body
closely resembling the earth in its
constitution and structure. 1t is evil
dent from many considerations that
meteorites are of fragmentary form
when they enter the earth's atmos-
phere. If they are large they are
often broken again, and yet again
during their plunge through the at
mosphere the violent descriptions re-
sembling explosions, but it is usual
ly clear that they were of irregular
shape to begin with.
This his suggested the theory that
they may be fragments of an eX-
ploded world.
Although carbon occurs In the
meteorites. both crystallized in the
form of exceedingly minute dia-
monds, and as uncrystallized graph
lite, no trace of organic remains has
ever been found in them. But there
are traces of many metals, such as
gold, lead, platinum, silver, ETC., in
very minute quantities.
In contradistinction to the theory
of the earth origin of meteorites
/ it has been argued that they may
! have been shot out of the giant vol.
canoes of the moon in long pas
agest, but there are some very seri.
Gus difficulties in the way of this hy.
/ pothesis. Mr.. Chamberlain, the in.
ventor of the planetesimal theory
of the origin OF the solar systems
has the interesting suggestion thai
meteorites may be the fragments o.
| bodies (planets) broken up by the
! passage of some immense mass neal
enough to produce disruptive tida
strains. TO sum up, the real. origir
of meteorites remains to be discov'
cred.
/ VICTORY LTRER1'X LOAN