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him more of that character which constitutes him God. In short, it is the more theistic view of the two.

This hypothesis has also the merit of dating the commencement of the evolutions of matter-which to some extent all must admit-back to the very point beyond which it is impossible for science to predicate any thing except to drop the universe into the hands of a First Cause. It places science in the position where, instead of suggesting a query or doubt, she naturally, and inevitably, and cheerfully pronounces the name of God.

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CHAPTER V.

THE REIGN OF FIRE,

HATEVER may be thought of the evidence bearing upon the question of the former gaseous condition of our world, or of the entire solar system, it is generally admitted that the evidence of former igneous fluidity is somewhat conclusive. This is a doctrine which we may regard as resting on legitimate geological data. This is a condition of the world we may proceed to contemplate without serious misgivings. Our earth was once a selfluminous star.

At the temperature which would fuse the mass of the rocks, all the more volatile substances could only exist in the form of an elastic vapor surrounding the earth. All the carbon in the world must have existed in the form of carbonic acid; all the sulphur as sulphurous acid; all the chlorine as chlorhydric acid; all the water as an invisible elastic vapor, extending out beyond the limits of the present atmosphere. There could hence be upon the earth no vegetation, no animals, no limestone, no salt, no gypsum, no water. All that we now behold must have been represented by a glowing, liquid nucleus, enveloped in a dense atmosphere of burning acrid vapors. This orb, by the immutable laws of physics, must have revolved upon its axis. and performed its revolutions around the sun. The sun and moon (if the latter existed) must have raised the fiery ocean to a tidal wave which rolled around the globe-the type of an action which has continued to the present period. There were also day and night. The sun rose in

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the morning, and sent a lurid ray through the dense, refractive atmosphere, and at night sank into the smoke that ascended from a burning world. The morning and evening twilight almost met each other in the midnight zenith, so high and so refractive was the heterogeneous atmosphere. But there was no need of twilight. An ocean of fire sent up to the nocturnal heavens a glare that was more fearful than the poisoned ray of the feebly-shining Here was chaos. Here was the death and silence of the primeval ages, when the Uncreated alone looked on, and saw order, and beauty, and life germinating in the heart of universal discord.

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In obedience to the law of thermal equilibrium-a law which undoubtedly rose into being with the birth of matter—the high temperature of the earth gradually subsided through radiation into external space. A crystallization · of the least fusible elements and simple compounds eventually took place in the superficial portions of the molten mass. This process continued till a crystalline crust had been formed, resting upon the liquid mass which still constituted the chief bulk of the globe.

It has sometimes been objected to this view that the solidified materials would possess superior density, and would, accordingly, sink into the liquid portions. If this were so, the solidification of such a molten mass would either commence at the centre, or a uniform refrigeration would proceed till the whole would suddenly be consolidated. It is the general belief that the central portions of the earth still remain in a molten condition, while the habitable exterior is but a comparatively thin crust. [See Appendix, Note I.] If this belief is well founded, the first solidified portions did not descend toward the centre. Moreover, we know that, in the case of water and several other substances, the newly-solidified parts are less dense,

and float upon the liquid portions. This apparent exception to the law of expansion by heat is accounted for by supposing that, when the molecules of a solidifying fluid arrange themselves in a regular crystalline manner, they inclose certain minute spaces, so that the resulting crystal is a little more bulky than the unarranged molecules from which it was constructed. And this may be the case, even though a cooler temperature has caused them to shrink into closer proximity (for they are never in contact) than before crystallization. If this law applies to the refrigeration of water, type-metal, iron, and other substances, we may reasonably infer it to be a general law of matter. We should expect, then, that crystals of quartz would float upon molten quartz, or solid trap upon molten trap, just as solid iron floats upon molten iron, or solid ice upon molten ice. We have, therefore, not only evidences of the fact of a forming crust, but also a probable means of accounting for it.

We may conclude, then, that a solid film began to form over the surface of the molten sea. But the earth was even then, as from the beginning, obedient to the law of axial rotation; and the sun and moon reached forth, with their attractive influences, to solicit the mobile rocks into tidal elevations. As the wave pursued the moon around the earth, it daily ruptured the forming film, and only a wilderness of floating fragments remained, strewn over the surface of the fiery abyss. In due time, however-let us be liberal in our concessions of time-the rocking and jostling fragments became permanently frozen together, as the broken ice of Arctic seas, after being worried by winds and currents, seizes an interval of calm to consolidate into a vast and rugged floe. So the rock-floe of this fiery ocean formed, at length, a bridge of rough and sturdy strength. It was a mixed conglomerate of crystalline fragments, such

as we now witness in some of the granites, which are mixtures of quartz, feldspar, and .mica; or the syenites, which are mixtures of quartz, feldspar, and hornblende; or the diorites, which are mostly mixtures of feldspar and hornblende. Or, perchance, the solidification took place under such circumstances that the crystallization was more obscure, as in the various dolerites, which every one admits to have been born of fire. We say that the process of refrigeration must have resulted in such rocks as these; and it is a curious and instructive fact, that when we turn our attention to an examination of the oldest rocks, we find granites, and syenites, and diorites, and dolerites resting where we expected them, underneath the rocks that came into being after water existed upon the earth, spreading out their bases in every direction, and constituting the very abutment which supports the lithological pile. We thus trace a certain succession of events which must occur in accordance with the established laws of physics, and find the series of sequents confirmed by the facts of the rocks themselves. Though this mode of reasoning is not in the spirit of modern natural science, it must always lead us to the truth if we reason correctly. Nevertheless, it is seldom the case that we are justified in the attempt to predicate the phenomena from the laws which involve them, as long as it is our privilege to confirm the laws by a study of the phenomena. In the present instance, the history of science shows that the laws were first arrived at by a careful induction from facts; and the little deductive reasoning in which we have indulged is but tracing the thread a little farther back, with the phenomenon it hangs upon all the time in full view.

In the process of refrigeration the stiffening crust would become too large for the nucleus within. This would necessarily result from the more rapid contraction of the more

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