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highly heated portions. If the solid and the molten portions suffered equal losses of heat, the molten, by shrinking the most, became too small for the enveloping crust. The crust, there

fore, must wrinkle, to fit the shrinking nucleus. Thus incipient inequalities of the surface began to appear. These were the germs of mountains and of continents. From a new-born wrinkle

grew the lofty Cordillera.

A scene of terrific sublimity approaches. As yet

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а

a

b

a

Fig. 13. Ideal Section of the Earth in primeval times. a, a, a. The surface when solidification first commenced.

b,

b, b. Wrinkles developed in the crust by the shrink

age of the nucleus.

no water existed upon the earth. No rain had fallen upon the parched and blackened crust. All the water which now fills the oceans, and the rivers, and the lakes-all which saturates the atmosphere, and the soil, and the rocks-rested then upon the earth as an arid, elastic, invisible vapor, extending an unknown distance into surrounding space. This vapor was not cloudlike, but intensely hot and transparent. It was a gas, like the steam just issuing from the escape-pipe of a steam-boiler. The time had now arrived, however, when the remoter regions to which this aqueous gas extended began to be so far reduced in temperature as to cause condensation to begin― as the heated steam, rushing from the locomotive, soon

cools into a cloud of visible mist. An intelligence located upon our earth at this epoch would have seen the dusky atmosphere begin to thicken. In the far-off regions, wisps of vapor crept along the sky, as cirrhi in our day foretoken the gathering storm. They grew, and thickened, and darkened till a pall of impending clouds enwrapped the earth, and the light of sun, and moon, and star was shut out for a geological age.

Particle drew particle to itself, and rain-drops began to precipitate themselves through the lower strata of the fervid atmosphere. In their descent they were scorched to evaporation, as the meteor's light vanishes in mid-heaven. The vapors, hurrying back to the bosom of the cloud, were again sent forth, again to be consumed. At length they reached the fervid crust, but only to be exploded into vapor and driven back to the overburdened cloud, which had an ocean to transfer to the earth. The clouds poured the ocean continually forth, and the seething crust continually rejected the offering. The field between the cloud and the earth was one stupendous scene of ebullition.*

But the descent of rains and the ascent of vapors disturbed the electricities of the elements. In the midst of this cosmical contest between fire and water, the voices of heaven's artillery were heard. Lightnings darted through the Cimmerian gloom, and world-convulsing thunders echoed through the universe.

"The sky is changed! and such a change! Oh, night,

And storm and darkness!"

* Those who are acquainted with Figuier's interesting works will note a remarkable correspondence between his treatment of this subject and my own. It is but justice, therefore, to state that these chapters were drawn up long before the work of Figuier appeared. This, indeed, has been my conception of these primeval scenes since 1856; and it was in print in 1857.

Fig. 14. The Primeval Storm.

A

CHAPTER VI.

OLD OCEAN COMMENCES WORK.

THOUSAND years of storm and lightning have passed, and the primeval tempest is drawing to a close. The waters are now permitted to rest upon the surface. By degrees the clouds are exhausted, and sunlight filters through the thinned envelope. As the morning of another geological epoch dawns, it reveals the change of scene. The surface which, in the preceding age, was scorched and arid, is now a universal sea of tepid waters. The earliest ocean enveloped the earth on every hand. A few isolated granite summits perhaps protruded above the watery waste. Around their bases careered the surges which gnawed at their foundations. Geology is unable to aver that any of them survived the denudations of this first detrital period. The demands of nature for material from which to lay the thick and massive foundations of the stratified pile of rocks were enormous, and it is probable that whole mountains were quarried level by the energies of this young, fresh, and all-embracing ocean. Probably, however, the nuclei of some of our oldest mountain masses, though subsequently elevated to their present altitudes, may be regarded as the remnants of the granite knobs that reared their frowning and angular visages above the primordial deep. If so, the erosion of the waves and the battering of the tempests have given to their sides and heads a smooth and bald rotundity. But most, if not all of the original pinnacles of the earth's crust have been leveled to the water's surface and spread over the floor of the

sea. To-day we may gather up the fragments, not from the bottom of the sea, but raised again mountain high, or incorporated into the fabric of new-built continents! Sublime ruins! What are the marbles of Nineveh, or the columns of the Parthenon, in comparison with these hoary relics of Nature's primeval structures?

I said that the fury of the waves strewed the ocean's bed with the ruins of these ancient islands. This is no fancy. The demonstration is before our eyes. The floor of the sea was first formed of rocks that had cooled from a state of fusion. The few islands that existed were but exposed portions of this floor. The débris scattered over this foundation would be arranged in layers, as water always ar ranges its sediments. The coarser materials would be transported by the more powerful action and deposited in one place; the finer materials would be carried beyond by

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Fig. 15. Shore Erosion and Distribution of Sediments.

C.

a, a. The primordial igneous crust. b. A sea-side cliff gnawed by the waves. The ordinary sea-level. d. The ruins of the cliff-the coarser deposited near the shore, and the finer floated to greater depths.

the feebler agency, and deposited in a remoter region. Thus some of the first-formed strata would be finer and others would be coarser; but all must be composed of materials derived from the pre-existing rocks. This deduction is again corroborated by well-known facts. Every where do we find reposing upon the ancient igneous floor a bed of stratified materials composed of the same constituent

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