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and let the dry land appear. And it was so."— Genesis, i. 9.

In attempting to search into the secondary causes which may have been called into action, when the channel of the sea was hollowed out, and the mountains were upheaved from the abyss, it behoves us to walk with the most humble circumspection. A cosmogonist has said, "that man who has weighed the planets and measured their distances, may presume to trace the operations by which the surface of the globe was arranged." The reproach of presumption will indeed be incurred, if we do not travel closely in the inductive path. We must, above all, beware lest we be misled by such a vague analogy, as that offered in the preceding quotation. The diameters, densities, and movements, of the planets, are present objects of measurement, as we remarked in the Introduction. Man may accurately observe the whole series of changes through which they run, and from his observations, compute their weights and distances by a rigid geometry. But he was not permitted to witness the series of changes through which the materials of our earth have passed, in attaining their actual arrangement, and thus the Cosmogonist wants data of kindred certainty, with those possessed by the Astronomer.

Multiplied observations have shown, that the crust of the earth is composed superficially, or to a moderate depth of certain stratiform or schistose rocks, which being devoid of organic remains, are termed primitive. We shall at present confine our attention to two of them, called Gneiss and Micaslate. These are arranged in planes usually parallel

to each other, the Mica-slate being, for the most part, uppermost. We have reason to believe, that hardly any district of the terrestrial surface is destitute of these great slaty rocks, though in many places they may be deeply covered over with secondary formations, and therefore inaccessible. Gneiss constitutes the body of the Himmalaya mountains, and abounds among the Andes, Alps, Urals, Pyrenees. It forms also Ross island, the most northern known land of the globe. Mica-slate is nearly co-extensive. But their wide-stretched foliated planes, are seldom or never horizontal, or concentric with the curvature of the earth. They usually lie at highly inclined angles, like tables resting on their edges, in a nearly vertical position. In very many localities, vast irregular masses of Granite, are seen rising up through the schistose fields, as if these had been upheaved and dislocated by its protrusion, and were thrown like mantles round its shoulders and base.

We therefore conclude that the primordial earth, as it lay beneath the circumfused abyss, was at first endowed with concentric coats of gneiss, mica-slate, and the other primitive schists; that at the recorded command of the Almighty, a general eruption and protrusion of the granitic, syenitic, porphyritic, and other unstratified rocks, took place, which broke up and elevated the schists into nearly vertical planes, similar to what now exist, leaving commensurate excavations for the basin of the sea.

In meditating on this mighty operation, though we may shrink from the overwhelming scene, and feel. our faculties abased, nay annihilated as it were, in the presence of that Power, "who hath measured the

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waters in the hollow of his hand, weighed the mountains in scales, and the hills in a balance; who sitteth upon the circle of the earth, and stretcheth out the heavens as a curtain," yet the magnitude of these terrestrial disruptions, will create no difficulty in the mind of the Astronomer, familiar with acts of Omnipotence incomparably more stupendous. Even the geographer would smile at the geologist, who should ask for Deity a countless lapse of ages to build up on the Earth its superficial scaffolding, whose size is to its total bulk, as the roughness of the rind, to the ball of the orange.

In treating of Primitive Formations, in the next chapter I shall adduce such evidence as will render the igneous origin of the unstratified rocks, more than probable, and demonstrate their agency in upheaving the schists, and causing the earth to deviate in many points of its surface, from its first form of a geometrical spheroid.

Before entering on these geological details, however, it will be right to consider the properties of water, and the creation of organic beings.

I. WATER.-There are few things endowed with more marvellous properties, or which are less studied and understood, than water. The artist, indeed, appreciates its value in one respect, as an element of the picturesque, capable of giving life and splendour to the landscape. The lover of rural nature is also sensible of its charms; whether it murmurs in a brook, rolls in a foaming cataract, or expands into the silvery mirror of a lake. Hence the Painter and the Poet have vied with each other, to celebrate these emanations of creative kindness.

But higher and deeper thoughts than any which external beauty can suggest, fill the mind that contemplates the internal constitution of this Protean liquid. Though in mass it is incompressible, and able to burst a passage through the strongest metal or rock, yet its particles form a fluid assemblage, softer than ermine, and yielding to the lightest touch. Obedient to the laws of gravitation, it enjoys singular prerogatives. Each invisible atom presses solely for itself, neither giving nor receiving aid from its associates. It weighs, not only like solids, from above downwards, but laterally and upwards, with equivalent gravity. Possessed of perfect mobility, it never wearies in its journey, till it reaches the level plane of repose. Without shape, it is susceptible of every figure, and the parent of myriads of crystalline forms. Capable of being aggregated in an ocean mass, yet renouncing its cohesive attraction before the feeblest power, it becomes divisible into the rarest exhalation. It exerts at one time an impulsive force, nearly irresistible, before which even the mountain bows its head, and crumbles into dust; and at another, it gives way to the light canoe. Just dense enough to float the pine, and afford a buoyant highway for ships, it is rare enough to permit the fleetest motions of its finny tribes. Had it been more attenuated, it would not have served the navigator; and if either denser or rarer, in a very slight degree, fish could not have swam in it.

This water, by its mysterious tenuity, loosens the indurated soil, enters the invisible pores of plants, passes freely through all their vessels, expands in

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the filmy blossom, and is an element of the fleeting aroma. But these fluid particles can be chained together in the firmest cohesion: in which state it may exhibit either the hardness of rock, or the softness of eider-down. Enormous blocks of water thus stand in immoveable columns, surmounting the loftiest pinnacles of our globe. How different are these from the soft insinuating liquid, which is the circulating medium of all organic life!

Let us now search still more minutely into the mystery of water. In its purest form, we view it as a compound of spherical atoms of oxygen and hydrogen, not confusedly blended, but joined in definite proportions; not placed in absolute contact, but closely adjoining each other by select points or poles of slight mutual attraction. Hence these all glide over one another, so as to pass through microscopic orifices, and recede at the least inequality of pressure. It is this constitution which makes its mass permeable to fish and floating bodies. The plain and vulgar element is now seen to be a most artificial assemblage of the bases of vital and inflammable airs; substances, in their insulated state, endowed with no plain or vulgar properties. Associated by chemical attraction with the element of coal, the three compose the concrete matter of the vegetable world, from the heart of the teak tree, to the essence of the rose. If into this triple alliance, be introduced azote, already spoken of as the main constituent of the atmosphere, that fourfold partnership will result, which constitutes the basis of all animal substance, whatever organic shape it may