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a degree that not years but centuries are required for its chronicle. Even the abrading of that description of rocks where they form the boldest sea-coast, by the violence of storms added to the ordinary action of water and weather, (an addition of great power,) has not materially altered the outline of such shores in Cornwall, the west and north of Scotland, Norway, and many other countries, since the beginning of our historical knowledge. But the action of a fresh water river infringing upon hard rocks, is much more feeble."-Smith.
Every step we take in it (geology) forces us to make unlimited drafts on antiquity."Scrope, in Smith.
“The detritus of the first dry lands, being drifted into the sea, and there spread out into extensive beds of mud, and sand, and gravel, would for ever have remained beneath the surface of the water, had not other forces been subsequently employed to raise them into dry land. These forces appear to have been the same expansive powers of heat and vapour, which, haring cansed the elevation of the first raised portions of the fundamental crystalline rocks, continued their energies through all succeeding geological epochs, and still exert them in producing the phenornena of active volcanoes.”—Buckland.
“ All observers admit that the strata were formed beneath the water, and have subsequenuly been converted into dry land.”—Ibid.
“The first appearance of stratification is in the rock called Gneiss. This is composed of the same materials as granite, on the irregular outline of which it rests. Over the Gneiss, come the beds of Mica, Shist, and Slates, whose thickness, like that of the Gneiss, cannot be ascertained, on account of the intervention of other rocks.' Their inode of formation is proved by the most striking characters to have been the same as that of the Gneiss. If we should venture to estimate the united thickness of this class, added to the Gneissic, at three or even four miles, we could not be charged with exaggeration." Smith.
6. The thickness of these strata we know to be enormous. These depths are discovered by geological observations and inferences—that they extend to many miles was also proved. We have every reason to know from what is taking place on our own earth, that the accumulation of materials at the bottom of the ocean, is a work infinitely slow. We are sure that such an accumulation as should produce the primary strata, as we now see them, must have occupied a space, from the contemplation of which the mind shrinks.”_ McCulloch, as quoted by Smith.
“Of the next group, the “siliceous, slatey, and limestone aggregates, to which the name silurian system is given,--the united thickness is about a mile and a half. Who then can calculate the periods of their derivation from the older formations, their deposition, their elevations, and distortions; their convulsions, penetrations, and alterations of the adjoining rocks, by frequent outbursts from the fiery liquid below, and other movements, till they were brought to their existing condition. It would seem perfectly impossible for any person, but moderately acquainted with the visible phenomena of volcanic regions, to escape the impression that myriads of ages must have been occupied in the production of these formations, before the creation of man and the adaptation of the earth's surface for his abode. Evidence to the same effect would accumulate upon us to a vast amount, in examining the old red sandstone, a reinarkable deposit, several thousand feet in thickness, found in some parts of Great Britain, more abundantly in Ireland, and either in resemblance, or in equivalence, in many foreign regions. Next we come to the mountain limestone, consisting almost entirely of the shells and coralline productions of sea animals, often a thousand and more feel in thickness. This formation is frequently more or less interposed among the beds of coal, composed of compressed vegetable matter, underlaid and overlaid with shales, and sand stones in every variety, often cffecting a thickness of three ihousand feet. The new red sandstone, advances us about another thousand feet.
“Olher changes implying probably some alteration in the disposition, and consequently the action of the fiery gulf below, marked the next great system, or series of rocks,the Oolitic. Its general thickness can be little less than half a mile. It is filled with the most convincing proofs of deposition from sea water both shallow and deep, the mingled waters of river mouths, and perhaps even fresh water of rivers and lakes.
“We arrive, in ascending, at the great masses of chalk, and its accompaniments of peculiar clays and sands, to the thickness of a thousand feet more. Though the lines of stratification are not here so visible as in the underlying formations, the evidence of deposition from watery mixture, and of very interesting effects from molecular and chemical attractions is so clear as to be irresistible.
“Our last stage of ascent comprehends the tertiary series ; a succession of beds,