sitions and catastrophes, as geognostic theorists have taught with regard to the primitive structure of the earth. What would be thought of a Naturalist who should pretend to determine the epoch of the world, at which the different layers of wood or bone were first formed out of some primordial chaos of vitality; when branches and limbs first began to sprout from simple trunks; when feathers, wool, and hair, first came forth for the protection of naked animals?

The third rotation of the terrestrial sphere, was accomplished amid a faint phosphorescence of the luminiferous ether. But towards its conclusion, a kingdom of life had been erected, which required a more vivid illumination. Accordingly the next revolution ushered in a golden dawn, the harbinger of the effulgent Day Star. Then the Sun was furnished with his phosphoric, or light exciting robe, a superficial luciferous film, which is probably the only peculiarity that distinguishes the structure of his body from that of his subject spheres. Created with the earth on the first day, when the law of universal gravitation was ordained to govern Heaven's isolated Orbs, he, with his brother stars, was not till the fourth,

"Invested with bright rays, jocund to run

His longitude through Heaven's high road."

Our ancient record of these events not only accords with every scientific principle; but intuitively defines the new function of measuring time which the orbs were fitted to perform, when they acquired their lucid exterior. "And GoD said, Let

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there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and for years. And God made two great lights: the greater light to rule the day, and the lesser light to rule the night: he made the stars also."

The vegetable tribes bloomed for one day in unenjoyed beauty and fragrance. But with the next rising sun, two vast classes of animal life, with their varied susceptibilities of pleasure, were summoned into existence. The waters were replenished with all their orders of vitality, from the cold elementary mollusca, to the warm blooded whale. From this period, too, commenced that deposition of marine exuvia on the ocean bed, which afterwards exposed to the eye of day by a mighty revulsion of the waters, have afforded to the fossil student, an exhaustless mine of observation. The winged inhabitants of the air were of coeval birth, and found abundant supplies prepared in the waters and the land, for their respective wants. The eagle now soared on adventurous wing round the naked granitic peaks, the albatross skimmed with unwearied flight the sparkling billow, and all the feathered songsters warbled in unison with the DIVINE benevolence.

Fishes and Fowls are classed together, as the creative work of the fifth day. Apparently these two orders of animals have little or nothing in common, and hence some sciolists have sneered at the collocation of Moses. But the true naturalist admires the scripture classification, because he perceives many fine analogies in it.

Flying modifies all the actions of birds, swimming

granite and gneiss, consists of 60 silica, 22 clay, and 14 potash.

The third of the primitive stratiform rocks, is clay-slate, or roofing-slate. It affords by analysis, 49 silica, 23 clay, 11 iron-oxide, and 5 potash.

If to these four bodies, quartz, mica, felspar, and clay-slate, called simple minerals, because they are of homogeneous aspect, we add hornblende and augite, we shall have before us the principal mineral constituents of the primitive shell of the globe.

Hornblende consists essentially of 42 silica, 30 iron-oxide, 12 clay, and 11 lime; and augite of 54 silica, 22 lime, 12 magnesia, and 10 iron-oxide.

Thus we see that silica, clay, lime, magnesia, iron-oxide, and potash, constitute by far the greater portion of the hard materials of the earth, as far as it has been explored.

Quartz, felspar, and mica, blended in distinguishable crystalline grains, constitute GRANITE.

Quartz, felspar, and mica, in crystalline scales or spangles constitute GNEISS.

The Mica-slate formation consists of the mineral of that name; interspersed with masses of quartz. Clay-slate rock is also the mineral of that name, interspersed occasionally with layers of quartz.

The mountains of Sienite, Porphyry, Hornblendeslate, Greenstone, and Basalt, are composed chiefly of the minerals hornblende, augite, and felspar variously mixed in form and proportion.

Such is a general outline of the substances which form the primitive mountain, and table-land edifices of the terrestrial spheroid. Reduced to their utmost state of simplicity, they become, in the

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hands of the analytical chemist, the combustible elements; silicon, aluminum, calcium, magnesium, potassium, iron; a mixture of which, at common temperatures, on coming into contact with water or moist air, would cause fire and explosion; and if the quantities were great, earthquakes and volcanic eruptions would ensue of commensurate magnitude.

That silica, and its associated bases, which are oxidized at the surface of the earth, and thus deprived of their elementary activity, exist at a moderate depth beneath that surface, devoid of oxygen, in the state of simple combustibles, there is little reason to doubt. The phenomena of earthquakes and volcanoes lead plainly to this conclusion. The heat observed in subterranean regions, progressively increasing as we descend, renders it further probable that these combustible elements exist there in a fluid state; an effect which would result from a very moderate heat, one greatly inferior to what is requisite for the fusion of their oxides.

The primitive envelope of the globe, seems to have originally consisted of concentric strata of gneiss, mica-slate, and clay-slate, with partial layers of semi-crystalline limestone; for such, with a few inconsiderable exceptions, constitute its rocky crust, and are spread over all its regions. These coats, however, no longer lie in layers concentric with the spheroid, but are thrown up into nearly vertical planes, and transpierced in many points by towering masses of granite and porphyry.

On the primordial spheroid covered with its illimitable ocean, these stratiform coats lay in hori

zontal planes; but with the gathering together of the waters, on the emergence of the land, they were heaved up abruptly into the nearly vertical tables, in which they now universally stand. This remarkable position corresponds to the eruptive violence that caused it. From the shoulders and flanks of the stupendous granite peaks, mantles of gneiss and mica-slate depend in magnificent drapery. These schistose coverings are arranged near the summit in folds almost upright, which lower down, become sloped off with clay-slate and limestone, into a gentle declivity. The coats of gneiss are often contorted into the most singular flexures of rock scenery, demonstrating a certain pliancy of texture at the instant of erection; resulting either from the moisture out of which it rose, or the softening influence of subterranean fire.

The wood-engraving at the bottom of this page, taken from D'Aubuisson, represents the usual structure of the primitive mountains. It is impossible for an unbiassed mind to contemplate this sketch, given by a Wernerian geologist, without seeing its entire conformity with the eruptive mode of formation.

The middle mass (1) is granite, bearing up between its central peaks, a portion (6) of the schistose