sent movements undisturbed through a coming eternity; while chemistry
illustrates the perpetual antagonism of the two great departments
of organical nature on our globe, by which the vital properties
of the atmosphere have been preserved for ages, as they may continue
forever, unimpaired; and, finally, geology informs us that the earth
has been, from the beginning, the theatre of constant and progressive
changes, having for their object the fitting it for the support of the
various races of beings which, in regular succession, have been its
inhabitants.
The first great change in the condition of the earth was the condensation
of its surface to a solid state, and the contraction of the
newly-formed crust during the process of cooling; by which the Plutonic
rocks of our system, the granite, porphyry and basalt, were
formed in unstratified and crystallized masses. These underlie all
the*other rocks, and aVe sometimes forced up through them by the
irresistible power of central heat. Their great eminences were separated
by valleys filled with seas, (through the condensation of the circum-
ambient vapors), along whose bottoms the stratified rocks were formed
by the deposition of various mineral matters resulting from the disintegration
of the primitive formations. The metamorphic rocks
were thus formed; and, after becoming solidified by the heat of the cooling
mass below them, were finally upheaved by the central force, and
composed immense masses in different parts of the globe. Most of the
considerable mountain ranges belong to this system. They rest upon
a basement of granite, and have been thrown by the upheaving forces
into positions inclining at all angles to the horizon. The upturned
edges of these primary strata in many places show a thickness of
fifteen or twenty miles — they were formed entirely from sediment
produced by the disintegration of the hardest rocks, and by the gradual
action of the elements; while their deposition, consolidation and
elevation must have required periods of time which the mind sb rin lr«
from contemplating.
The Koran declares that the world was created in two days; and
“ Omar the Learned,” for assigning a longer period, was obliged to
fly from his country, to escape the disgrace of recanting his opinions.
Happily, we live now under a more enlightened dispensation.
In these rocks we find no traces of organic remains to show that
the earth was yet inhabited by living beings. But the creation of the
earth consisted of a long succession of events, each occupying a distinct
geological period, and leaving indelible records of its history in
the solid crust of the globe. The creation of organized beings exhibits
a similar succession — each race appearing as soon as the earth
was prepared for its reception, continuing so long as the same state of
things existed, and vanishing when the improvement of the earth had
rendered it fit for the maintenance of a higher type of living creatures.-
All living creatures were exactly adapted through their organization
to the peculiar localities they were placed in. They perished when the
ccinditions necessary to their well-being were changed or ceased to exist.
In the next series of strata we find the earliest traces of those tribes
of organized beings which occupied the primeval earth, and have left
the monuments of their existence in the rocks which form their tombs.
These primary fossiliferous strata are entirely of marine origin,
having been formed at the bottom of the ocean; and they contain the
remains of marine animals ohly. The types of these animals are
easily recognized — they include representatives of all the great departments
of the animal k ingdom^but the species and even the
genera are entirely lost. The animals, however, all belong to the
lowest divisions of the different classes. Thus the radiata are represented
by zoophytes, crinoidea and polyps — each the lowest in their
respective classes. Mollusks, in like manner, exhibit only the lower
types; articulata are mostly confined to trilobites; and fishes of the
lowest forms are the sole representatives of the vertebrata: there are
here no reptiles, no birds, and no mammals.
These primary strata are many thousand feet in thickness, and
the organic remains imbedded in them, though belonging to a few
species, show that animal life already existed in immense profusion,
and extended over wide-spread regions of the globe. They flourished
for countless generations, and their remains are found reposing in
earth’s earliest sepulchres.
In the next Stage of the earth’s history we have the Silurian system.
Here the forms of life are more varied and abundant — species are
multiplied; fishes now make their appearance in numbers and varieties
corresponding with the improved conditions for their existence;
and sea-plants are found among the fossils of this era. In the old red
sandstone, the same orders are continued; new fishes are still more
abundant, and all the Silurian species have already disappeared.
These fossils, again, are-entirely distinct from the corresponding
species of the carboniferous era which succeeds them. Hot a single
fish found in the old red sandstone has been detected, either in the
silurian system on the 'one side or in the carboniferous on the other.
Throughout all subsequent geological eras similar changes took place,
and new species replaced the old at every new formation. In proportion
as the earth approached its perfect state, the organic types becamq
more complex; but the types originally created were never destroyed,'
they have been preserved through every succeeding modification and
improvement, up to their highest manifestation in man. Regarding
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