Bristol news. [volume] (Bristol, Va. & Tenn.) 1867-189?, 1872-03-22
SCIENTIFIC.
THE EARTH IN ITS MAN
HOOD
Rise and decline Of cur World
why the Noon and other
dead worlds have no wa
ter CIR their surface.
BY PROF. ]. BRAINERD.

name the elements that form our com
cts. Even the fixed stars, whose dis
tances defy computation, are shown to
be composed of matter like that with
which we are in contact.
We learn that the planets that COM
pose our owu solar system have peri
Ods in their existence, answering to
those of infancy, maturity, and age,
and that the elements of their compo-
sitiOn are now, and have been, gradu-
ally passing from an incOndesceDt
state, like gas, to that of fluid or SOL
id form.
In the study Of these phenomena we
have accumulative evidence that the
materials that constitute our globe
were once in a state of elementary,
self-luminOus vapOr, occupying an eX-
tent equal, perhaps TO the orbit of the
moon, and having a disc-like form,
like that which now surrounds the
sun, called the zodiacal light.
the revelations of geology show
that the earth was once without a SOL
id crust, melted, fluid mass of min
eral matter. surrounded by a dense
and heated atmosphere, containing
the elements which now form the wa
ters of the ocean. The union of oXy-
gen and hydrogen, in the form of Wa
ter, is known to produce an intense
heat, heat sufficient to melt the most
refractory bodies known; in fact. this
is true in relation to the combination
of oxygen with any other element
than hydrogen: and as it is known
that oxygen constitutes about one-half
of the substance of our globe, being
found in union with almost every
other element. it is no marvel that
the primitive earth should have been
in fluid state from heat, arising from
such chemical unions, and surrounded
by a dense and luminous atmosphere
Of thousands of miles in depth, radia-
ting light and heat into the regions
of space in the same manner that the
sun now gives light and heat to US
And this radiation of heat from the
earth has been incessant through un-
numbered ages, and still continues
and however slow may be this action
at the present time, it is nevertheless
certain; and consequences of this
cooling process was early manifested,
resulting in an increasing density of
the earth as a whole, contracting its
circumference, thus causing inequali-
ties in its surface, forming both the
bed Of the ocean and great mountain
ranges.
Primarily, the changes upon the
earth's surface were due wholly to the
contraction of its crust by loss of heat,
but after the formation of the ocean,
by the condensation of the watery va
pOr that surrounded the granite globe,
other agencies were brought into ac-
ton to produce such changes.
All the stratified rocks have been
formed by the agency of water, usually
by the joint action of the mechanical
arrangement of undissolved material
of older rocks, and the chemical dispo-
sitiOn of matter held in solution, by
which the undIssOlved particles were
cemented together; or, the statilied
rocks may have been altogether formed
bv chemical deposition and crystaliZa-
ton. and stratified by Encouragement
of particles.
The thickness of the crust of the
earth at the present time, embracing
both the granite and stIatified rocks.
varies from ten to thirty miles, and
this thickness is constantly increasing,
both from the disposition of new mat
ter in the depths of the ocean, and the
cooling of the underlying granite.
The vast interior of nearly eight
thousand miles in one vast cauldron
of melted matter, pressed upon all sides
by the constantly contracting solid
crust that surrounds it, finding only
occasional vent in volcanic eruptions in
the form of melted lava. This fluid
mass, which constitutes the nucleus of
the earth's crust. is fluctuating but not
compressible,- and the solid rock,
whether stratified or primitive, floats
upon its surface as ice floats upon wa
ter. The cooling process constantly
going on in the earth's crust caused a
pressue upon the interior fluid mass,
and would, were no other agencies
brought into action, produce gradu-
al and quiet flow oflava from the nat
ural vents with which the crust of the
earth is provided.
The known contraction of granite
rock from a temperature ofsix hun
dred degrees "a red heat to sixty, (the
mean temperature of the surface rock
would shorten the circumference OF
the earth crust more than fifty miles;
and to this agent may be attributed
the formation of our most stupendous
mountain ranges and the great de-
pressious of the oceans bed.
The ocean has depth in many pla-
ces of more than five miles, and our
highest mountains present a cores
ponding altitude; but were those
mountains to be leveled, the beds OF
the seas and oceans filled up and the
waters of the globe equally distributed
over its surface, the fluid envelope
would not exceed three thousand feet
in depth, about thTee-fifths of a
mile.)
That the mean temperature of the
earth is constantly being reduced is q
fact admitted by such men as Fourier,
Hersheil, Won Humboldt, and others,
and were its present solid crust ofsuffl,
cient strength to sustain the pressure
of its own weight, the final refrigera-
ton of Its interior, molten matter,
would cause the formation of caverns
equaling in extent and capacity zone
of nine miles in depth, encircling the
entire globe; sufficient in extent TO en-
gulph ten times the quantity of water
now upon the surface of our earth.
Water and humid atmosphere are
essential to the development of both
vegetable and animal life, and any ma
terial change in regard to the distribu-
ton of this fluid would seriously af-
feet such Development.
We learn from the testimony of the
rocks that there has been period in
the history of our planet when no or
ganic form existed a period in which
the positive and negative elements,
the metallic and non-metallic, became
chemically united. From the same
source we learn that the simplest forms
of life were first revealed, and that in
succession higher and still higher or
ders were Introduced, till at last the