Yorkville enquirer. [volume] (Yorkville, S.C.) 1855-2006, 1907-12-06
THE EARTH's INTERIOR.
Our Planets Core 10 Liquid, Yet It's
AZ Rigid A. Steel.

Our Planets Core 10 Liquid, Yet It's
AZ Rigid As Steel.
The idea that the interior Of the globe
is composed Of flowing lava has long
since been abandoned. but the picture
that modern science offers Of the In
side OF the earth is hardly less ap-
palling. All Investigations unite to
prove that the heat increases as we de-
scend deeper in the terrestrial crust
at such a rate that forty or fifty miles
down no substance with which we are
acquainted could remain unmelted. And
yet the same science tells US that the
core Of the globe Is enormously more
rigid than the hardest steel. This ap-
parent contradiction is due to the tre-
,pendous pressure inside the earth. No
rock and no metal can, remain there In
the state in which we see 1t on the sur
face. Its molecules must lose the ad-'
herence Characteristic of solid bodies
In consequence Of the heat, but still
they are not free to flow like an ordi-
nary liquid, because Of the compression
to which they are subjected.
| The phenomena Of earthquakes have
given wonderful information about the
internal state Of the globe. All OBJ
servations show that the shocks Of
earthquakes are confined to a thin up
per shell. They originate at a depth
Of only a few miles at the most. But
the vibrations which they set going
are felt all through the earth, often ex-
tending to the antipodes. The great
core, held rigid by the pressure, Is ex-
tremely elastic, and 1t responds to
shock like ball Of steel or OF glass.
The density Of the earth increases to-
ward the center. It Is only In the up
per part of the crust that local move
ments can take place. causing shocks
and changes of level at the surface.
Deeper down everything is gripped and
Itmmovable. except, as already remark
ed, that the molecules Of the rocks and
metals there are subject to vibration
like those of bell against which a
blow is struck.
But this is not all. Whenever local
release from the pressure Is brought
about by changes near the surface the
potentially liquid but effectually solid
core at that point may suddenly be-
come fluid and gush forth through q
volcanic throat or other vent. But
such effects cannot extend to any great
depth. Nothing comes to US from the
vast interior mass. That remains q
perpetual mystery, far beyond the
searching hand Of science. Indirectly,
however, we may learn much about It.
Astronomical considerations throw a
great deal of light upon the subject.
We see that through the planetary sys-
tenn rotating globes are fiattened at the
poles. The same thing is true Of the
earth. Its equator bulges; its polar
regions are drawn inward. Mechan-
ical laws assure US that the cause Is
to be found in the fact that the earth
and the other planets have assumed
shape under the influence Of the CEN
trifugal force of their rotation. That
force Is necessarily greatest at the
equator Beginning as completed mol
ten bodies, they have commenced to
solidify at the surface after having as
sumed an ellifiordal form due to their
rotation.
Another very significant fact Is that
the shape Of the earth corresponds with
that which a globe rotating with It's
velocity would have II composed or
materials arranged to their density
that is to say. growing denser toward
the center. The heaviest materials
must be deep down in the globe; the
lighter materials have remained at the
surface. This again corresponds with
the facts of observation. We know
the total weight" and the average
density Of the earth. 1t weighs" six
sextillions of tons, and its average
density is five and half times that or
water. But the substances composing
the crust Of the earth have an average
density of twice that Of water. 1t
follows that the heaviest things In the
earth, on the average, exist deep with
In its exterior. For all that we can
tell, its inner core may be wholly me-
tallic. At the center there is probably
an enormous aggregation Of dense me-
tallic substances.
An indication that the inner parts OF
the earth consist largely II not mainly
of iron Is to be found in the magnet
ism Of the globe. The earth is great
permanent magnet. II we could learn
the facts 1t might turn out that iron
Is the most abundant substance In the
solar system and perhaps in the whole
universe. The majority Of the meteo-
rites that fall upon the earth consist or
solid iron. Blow the earth to pieces
and in the resulting cloud Of fragments
the rocks that we are familiar with
would be almost imperceptible. There
would be a rain of iron and other met
ais descending upon the moon and up
on any other attracting body in the VI
cinity.
This view Of the interior Of the globe
disposes of the notion, so pictur-
Iesquely developed in one Of Jules
Iverne's romances, Of the existence OF
vast cavernous openings in the inte-
rior of the earth. Such void spaces.
though on no large scale, may exist
in the upper part Of the crust, but not
at great depth. The earth Is effect
lively more solid than cannon ball,
and the movable rocks composing Its
crust are like a film Of rust on the
hard metal-Professor Garrett p. Ser
viss in New York American.
| "a Mr.. Hammerkick-There was alb
solutely no taste to that turkey 1
bought Of you. The Progressive Far
mer-Well, taste isn't the main thing
That turkey was the most nutritious
bird I ever sold: 1t had been fattened