The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1906-04-22
as probably molten below twenty

| SL&ct i4G SS1ItE Is nUgS. T2DI0i
rotating, spheroidal mass. subject I
} the attractions of the neighborin
heavenly bodies. Yet the nathernati
clans have shown that it resists thes
! strains as if it were as rigid as tn
J | best steel. A great mobile, fluid in
, terror is an impossibflity Again. W.
, readily apprehend on reflection tina
the outer portions of the earth rest upol
the inner portions and are supported
by them. If so fiat an arch as is an,
conceivable section of the earth is sub
mitted TO mathematical analysis. it a
once appears that even We're it's resist
ing powers many times those of the
best steel, and many more times those
of the best rock. the arch would col.
lapse. These outer shells crush dowr
upon the inner portions with almost
| Uncomfortable pressure. At six miles
the minutest cavities are welded to-
gether, for the pressure is eighteen
tons to the square inch. Now, pressure
makes it more difficult for things to
melt: in other words. it raises the fus-
ing-point- lava which would melt at
22000 on the surface requires a much
| higher temperature at the pressures
prevailing at twenty-five miles. We do
/
these conditions are beyond expert
| ment but we believe that pressure in
| creases SO rapidly that fusion on a
grand scale becomes an impossibility
| and the earth is virtually a solid body.
Yet solids under overmastering pres
sure develop in themselves a viseous
flow. Professor Frank D. Adams of
Montreal has compressed tightly con-
fined cylinders of Carrara marble to
disks without destroying their cohesion
in the least. Therefore the rock in the
interior might stand at a temperature
far above its normal fusing-pont; it
might, though solid yet be able to de-
velop viscous flow toward a point
of diminished pressure; it might, if at
this point it could turn upward and
proceed toward the surface, pass into
the molten state as the pressure di-
minished.
One other preliminary conception,
and the explanation of volcanoes is
before US. The earth is a shrinking
body. The ridges of the mountains.
with their bent and folded strata prove
this; but whether the earth shrinks be-
cause it loses heat and contracts, or
whether, from the drag of the tagging
tides and trade-windS, it's speed of ro-
tation is diminishing and the conse-
Quent loss of energy leads it to change
toward a sphere from its present shape
of a somewhat f1attened spheroid, or
whether from some cause as yet un-
known, we cannot say. The fact of
contraction is nevertheless insistent.
Now let us assume that because of
contractions a vast crack forms, and
the sides, while still resting on the
underlying rock, draw apart. Suppose
the crack suddenly extends to the
depths, and with viscous flow the solid
rocks. urged on by the crushing pres
sure of the sides, ooze into it, move
upward, melt with diminishing pres
sure, and yield fluid, quickly moving
lava.
One other consideration now becomes
of great Importance. All experience
with lavas and volcanoes convinces us
that the molten rock is Surcharged
with gases and vapors of which water
or it's ASSOCIATED hydrogen and oxygen
are chief. 1t is necessary to speak of
water as ASSOCIATED because its critical
temperature, or the temperature at
which it is rent apart into oxygen and
hydrogen, is we'll below the melting
point of rocks. In the depths of the
earth the gases are kept confined by
the pressure; but as the lava rises,
they burst into the gaseous condition,
and they are not only explosive, but
combustible, and may yield actual
flames. BY just SO much they lower
the specific gravity Of the rising |
column and ease the task of the lower |
lying rock, the onward march of which |
elevates the lava to the surface. AS |
the column reaches the upper world |
the gases burst with explosive vio- |
lence and drive the shattered rock, it /
may be as at Krakatua, to the four |
quarters of the world. That the vapors |
also drive the lava upward, or even
that they are a more potent elevatory |
force than gravity itself is believed |
by many. and the thesis has much in |
it's favor. Some have thought, especial
ly in earlier days, that sea-water per-
colated downward and became involved
in the molten rock so as to furnish the |
gases. but the preponderance of opinion
is against it to-day, because of the
of understanding how water
could advance toward and into the
heated rock instead of being driven the
other way.
While lavas may and probably do
reach the surface in the way outlined,
yet it seems true that great bodies of
them must stand in the fluid condition
near the surface for long periods OF
time. We find, for example, that the
same vent in long course OF eruptions
Yields different kinds of lava: first
medium grade of moderate specinc
gravity, next successfully lighter kinds,
until in it's expiring gasps dense,
heavy variety closes the series. 1t is
exactly as if a vast complex. molten
mass that stood fluid in an internal
reservoir broke up into lighter portion
which hoated on the top and was first
appel off and a heavier portion which
1t the end came forth as the dregs and
CONCLUSION.
No phenomena deserve the descrip-
i've title of 1.-The Great Natural Gaia
,lysms'' SO well as earthquakes and
-oIcanoeS. Instead of attaining results
~ slow and gradual processes, they