The Corvallis gazette. [volume] (Corvallis, Or.) 1862-1899, 1885-10-09
WHY TIE EARTH oUAKE.,
The Forces Supposed to be at Work Thirty
Miles Beneath Us,

he Forces Supposed to be at Work Thtrtv
Miles Beneath Us.
Professor George H. Merriman, of
rutgers college, New Brunswick, has
made the crust of the earth study, and
aas written on the subject. He says:
while facts enough regarding the
extent OF the earthquake of Sunday
nave not come to hand to enable me to.
speak on the direction of the earth
wave OF its peculiar features as COM
pared with other earthquakes, yet some
thing may be said as to the latest con-
victions of students of science on the
nature of the earth below the point any
man can penetrate. That may lead us
to guess 1ntelligently at the cause of
earthquakes.
"You know the long received theory
Of the nature of the interior of the earth
was that it is molten mass, and that
we move around on a crust enveloping
the earth and caused by the cooling off
OF this mass on the inside. It is un-
doubtedly true that about thirty miles
below the earth's surface the tempera-
ture is so high that everything is in a
melted condition. We know this, be-
cause we have learned that every fifty
feet we penetrate into the earth there is
an increase of temperature cf about one
degree, and at distance of thirty miles
the heat is so great that any substance
we know of would melt.
Perhaps the melted mass is in the
form OF liquid. That whold be GER
tain but for the immense pressure on it.
The pressure is estimated at 10, 900 tons
on square foot. Of course scientific
men cannot experiment with matter at
a high temperature with a pressure of
IO,O0O tons to square foot, so we can
only guess what may be it's condition.
In talking about this melted mass thirty
miles under us the term water substance
is used by geologists.
How great is the distance through
this water substance we do not know,
but it is certain that its destiny increases
more and more, gradually, until the IN
terror of the earth is solid, probably,
from the inconceivable pressure 1000,
1000 or 5000 miles from the surface.
Sir William Thompson has demonstrat-
ed that the earth must have a core much
denser than the land and water we live
on. He points out the fact that if a
shell only thirty miles thi TX surrounded
a molten liquid mass extending from
one side of the earth through the CEN
tire to the other side, then the moon,
through law of gravitation, would dis
place the liquid or gas in the interior
OF the earth to such an extent that the
earth's crust would bulge out in the di-
rection of the moon, making a tide in
the solid crust of the earth, as certainly
as the skin of an orange bulges out when
you squeeze the fruit between the palms
of your hands. And this would be evil
dent to us because the ocean tides would
be almost, if not quite, imperceptible
to us. To withstand the attraction OF
the moon, the earth, Sir William says,
must be rigid as steel.
So we have the theory that the crust
of the earth floats on and imposes al i'm
mense weight on a water substance,
which is inconceivably hot. Now, as to
the way an earthquake may be caused.
Suppose moisture trickled gradually,
year after year, through this crust into
= heated mass. In our atmosphere
steam would be produced. Thirty
miles below us the pressure is SO great
that it is not likely that steam could be
generated. One thing. though; the
pressure of 10000 tons to the square
foot, pressure exerted in every direc-
tion, would be increased. Some effect
must be propuced down there, and it is
easy to see that if one place in the
earth's crust is weaker than another re-
gion where the water trickled in. then,
the weakest place must stand the.
strain 1t is not unreasonable to sup
pose that this pressure below might be
so great that the earth's covering was
shifted little to adapt itself to the pres
sure from below. This shifting of the,
crust is, in fact, the earthquake.
II believe this theory has the greater
reason on It's side, because earthquakes
Ire almost always in the region OF vol
canoes, and volcanoes are almost always
II or near the ocean.
"Another theory of earthquakes Is
hat as the earth is very gradually cool
ng off the crust is thickening on the
1nder side and cracks or assures on the
1nder side of the crust many miles deep
nav occur in consequence of the enor-
nous pressure, so that the water sub
stances rushes into new position with
force that would knock continent
,ut of shape if it took place on the earth's
surface. That motion would be suili-
,ient to produce q viabration thirty
niles distant.
"Whatever the cause of the earth
,uake on Sunday" added Professor
Merriman, II think the earth in the re-
non where it took place has either set
led into new position or is forced
pack into an old position from which it
Vas pushed by former earthquakes.
Castrating Lambs.