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whence M. Brogniart conjectures that the silex of ancient freshwater formations was precipitated where we now find it, from the waters of thermal springs.

Between the aquatic plants and animals of the ancient and modern deposits, the closest relation subsists; the genera in the two cases being nearly identical. In both cases, among the testacea, are lymneæ, planorbes, &c.; among the crustacea-the genus cypris; and among the plants, the genus chara, with its fossilized seed-vessel the gyrogonite. Beautiful engravings of the fossil charas of the Bakie rock-marl accompany Mr. Lyell's very interesting paper.

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The small point among the marginal figures, is the gyrogonite, or fossilized pericarpium of chara, found in the tufaceous limestone of the Bakie Loch; of the natural size. The large oval figure is the above magnified 20 diameters, and the round one, represents

the lower end, to which the stem was attached. The chara medicaginula of the lower freshwater formation of the Isle of Wight is nearly twice the above size, and different in its spires.

The magnitude of the ancient freshwater lakes is not without modern parallel, though nowadays, the deposition has become comparatively slow from the reduced temperature, and smaller dimensions of the present race of European testacea.*

If this earth be a school of virtue to man under the direction of Providence, and if public calamities be requisite to maintain its moral discipline over the short-lived race of the present day, what

Geol. Trans. 2d Series, Vol. II., p. 73.

PHYSICAL EVENTS SUBORDINATE TO MORAL. 349

penal prodigies would be necessary to restrain the wickedness of Cain and his apostate brood! The inspired historian does not indeed give, in his brief sketch of antediluvian society, any details of such occasional manifestations of Divine wrath, though the disordered fabric of the globe bears ample testimony to their repeated occurrence, but in his solemn account of the concluding catastrophe, he most explicitly ascribes the physical convulsions, to the indignation of Heaven. He tells us moreover, that Noah, favoured with a prophetic view of the coming calamity, built by Divine command a vast edifice of wood to float himself and family through an universal deluge, from which no other mode of escape would be possible. That Noah was commissioned to declare to the reckless mortals around him, the long-suffering of God, and to preach repentance, while the ark was preparing, St. Peter expressly informs us. We may readily imagine the derision with which the unparalleled architecture of the pious patriarch was regarded by his compatriots; and the insolent defiance with which they received the admonitions of the Almighty. That Noah's warning voice was seconded by miraculous powers over the phenomena of nature, we are not told. But as Moses, and all his great successors, were furnished with supernatural credentials of their prophetic mission, there is little reason to doubt that to Noah also such powers of controlling or predicting events might be delegated, as would strike terror, for a time at least, into the most depraved and the boldest hearts.

BOOK III-THE DELUGE,

IN WHICH THE CAUSES OF THE ANTECEDENT REVOLUTIONS OF
THE EARTH, AND ORGANIC BEINGS ARE CONSIDERED.

CHAP. I.-PHYSICAL RECORDS OF AN UNIVERSAL DELUGE, WHICH NEW-MODELLED THE EARTH.

"I CONCLUDE with MM. Deluc and Dolomieu," says the illustrious Cuvier, "that if there be any fact well established in geology, it is this, that the surface of our globe has suffered a great and sudden revolution, the period of which cannot be dated further back, than five or six thousand years. This revolution has on the one hand, ingulphed and caused to disappear, the countries formerly inhabited by men, and the animal species at present best known; and on the other, has laid bare the bottom of the last ocean, thus converting its channel into the now habitable earth."*

That a great expansive and subversive power exists within the crust of the earth, which has at remote periods, acted with prodigious force, raising up and laying dry those submarine strata, and transferring the waters of the ocean thence over ancient lands, is attested by innumerable phenoConcerning the chemical nature of this power, there can be little doubt. Modern volcanic eruptions, though merely its expiring efforts, clearly indicate, that the earthy and alkaline oxides of the terrestrial crust, exist interiorly in a metallic

mena.

* Baron Cuvier-Ossemens Fossiles, Discours Préliminaire, p. 134.

UNIVERSAL DISTRIBUTION OF DILUVIAL GRAVEL, 351

state, fused by the central heat, ready to produce explosion to any imaginable extent, on the influx of water.

Of this mighty deluge, the concomitant and effect of the transflux of the ocean which anciently covered a large portion of the present habitable earth, we have universal evidence. Nearly the whole table lands, and gentle acclivities of the mountains are covered with deposits of gravel and loam, to the production of which no cause now seen in action is adequate, and which can therefore be referred only to the waters of a sudden and transient deluge. This deposit is hence called diluvium by geologists. In it, the pebbles and loam are always promiscuously blended, whereas among the regular secondary and tertiary strata, they occur separate in alternate beds. The term alluvium is bestowed on the marl, sand, and gravel deposited by existing rivers and lakes, or on planes exposed to occasional inundation. The ablest writers, Cuvier, Buckland, Brogniart, Conybeare, &c. now adopt these distinctions.

"In the whole course of my geological travels," says the Rev. Dr. Buckland, "from Cornwall to Caithness, from Calais to the Carpathians, in Ireland or in Italy, I have scarcely ever gone a mile, without finding a perpetual succession of deposits of gravel, sand, or loam in situations that cannot be referred to the action of modern torrents, rivers or lakes, or any other existing causes; and with respect to the still more striking diluvial phenomenon of drifted masses of rocks, the greater part of the northern hemisphere, from Moscow to the Mis

sissipi, is described by various geological travellers, as strewed on its hills as well as valleys, with blocks of granite and other rocks of enormous magnitude, which have been drifted (mostly in a direction from north to south) a distance sometimes of many hundred miles from their native beds, across mountains, and valleys, lakes, and seas, by a force of water, which must have possessed a velocity to which nothing that occurs in the actual state of the globe affords the slightest parallel."

Theorists, particularly of the Huttonian creed, have greatly overrated the disintegrating power of streams on the surface of the globe, and the consequent extent of common alluvium. Their fiction of cosmogony required a transfer of the mountain elevations and table-lands to the bottom of the sea, and they did not fail to paint their rapid transport, and deposition there. To the erosion of a streamlet, however inconsiderable its size, they ascribed the excavation of every great valley which it traversed. But this is often a mere thread, compared to the sloping width of the valley, and should at the utmost have produced merely a narrow and precipitous glen. The observed action of such a brook is rather to fill up the dell through which it glides, than to enlarge its dimensions. We may ask these theorists, how the Gave in the territory of Bearn, could scoop out incognito, so to speak, the profound excavation, in whose bottom it is encased, near the bases of the Pic de Bergon above St. Sauveur, between two natural walls, several hundred feet high, composed of very hard petrosilex (chert), the flat surfaces and acute angles of which display

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