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glomerates would appear, not the result of a limited disturbance, but of one common to a considerable surface."*

Professor Phillips confirms this when he says

"The next succeeding deposit, which receives the name of red sandstone, or saliferous, or poecilitic formation. . . . . . almost universally fills a low or level country, out of which arise insulated of mountains of old strata or of pyrogenous groups and short ranges rocks. The system consists of many alternations of arenaceous and argillaceous members, with some less continuous interpositions of limestone usually impregnated with magnesia. Thus the whole is capable of being represented in one formula, which is well calculated to show both the agreement and differences usually observed in comparing distant parts of a stratified formation.Ӡ. . .

"Salt is associated with the upper parts of this system in England, France, and Germany, where the muschelkalk is quite as saliferous as the variegated marls to which, apparently, salt is confined in England. Upon the whole, therefore, the red sandstone system is a vast mass of sandy and argillaceous sediments of a peculiar aspect, accompanied more than any others yet known by salt and gypsum, generally deficient in organic remains, and only locally enclosing strata of limestone, which commonly are characterized by abundance of magnesia."+

The denuding and sweeping action of a vast body of water seems, by the following passage from Mr. Miller's work, to have likewise been recognised by him in the geological developments of those parts which he examined:

"The curtain again rises," says he, "a last day had at length come to the period of the middle formation; and in an ocean roughened by waves and agitated by currents, like the ocean which flowed over the conglomerate base of the system, we find new races of existences. The depositions of this upper ocean are of a mixed character; the beds are less uniform and continuous than at a greater

* Manual of Geology, by M. de la Beche, 2nd edition, pp. 409–412.

+ We would recommend our readers who may have the opportunity to refer to this formula.

Treatise, pp. 119, 120, 123.

depth. In some places they consist exclusively of sandstone, in others of conglomerate; and yet the sandstone and conglomerate seem, from their frequent occurrence on the same platform, to have been formed simultaneously. The transporting and depositing agents must have become more partial in their action than during the earlier period. They had their foci of strength and their circumferences of comparative weakness; and while the heavier pebbles which compose the conglomerate were in the course of being deposited in the foci, the lighter sand which composes the sandstone was settling in those outer skirts by which the foci were surrounded. At this stage, too, there are unequivocal marks in the northern localities, of extensive denudation. The older strata are cut away in some places to a considerable depth, and newer strata of the same formation deposited unconformably over them. There must have been partial upheavings and depressions, corresponding with the partial character of the depositions; and, as a necessary consequence, frequent shiftings of currents. The ocean, too, seems to have lessened its general

depth, and the bottom to have lain more exposed to the influence of the waves.

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We have already, in a former part of this work, alluded to one very important service performed by the debris here spoken of, namely, protection to the vegetable beds which now constitute our principal coal fields. It not only saved these from being washed away by the denuding influence of the water thus thrown into violent movement, but by covering them, it likewise preserved them effectually from the atmosphere which was shortly afterwards to be formed, and by their gaseous ingredients being thus confined, they were rendered fit for our present purposes, as great carbonaceous deposits. It must also be added, that another very wise and beneficent design was carried into execution, by the arrangement which impelled the water from the poles towards the equatorial regions. In the latter zone, the mountains having risen to a greater height by the increased centrifugal impetus, a proportional quantity of loose, stony, and earthy material would necessarily be requisite to fill up their deeper hollows, and more rocky and rugged acclivities; but as, at that period, the aggregate depth

* Old Red Sandstone, pp. 310, 311.

of the strata was uniform all over the spherical earth, it is evident, that the mere elevation of the protruded rocks, although to greater heights, would not have been sufficient to have supplied the debris required for that purpose. Hence, in the sudden rush of water, laden with earthy materials from either pole, towards the equatorial regions, and it being there brought to rest and made to unladen itself of its burden, we behold a wise and harmonious combination; wherein the several circumstances are made to concur towards the completion of the design then in contemplation. Nothing could have been better adapted for supplying the wants in these regions, and for completing the habitable portions of its surface, than this seasonable supply of earthy matter, borne along by the rushing water, and deposited where so much needed; while, at the same time, the more extreme latitudes were relieved, by disintegration and denudation, from an immense mass of loose material, which would have been positively prejudicial where it was originally formed, had it been there redeposited.

Other attendant circumstances, displaying the infinite wisdom of the whole design, ought, by no means, to be overlooked. We allude, in the first place, to the modified state of the oceanic water itself, which, during a protracted course of preparation, had been deprived of the greater part of those previously combined gases, which, had they been permitted to exist in the water at the period we now refer to, would have redissolved the earthy material which was designed to be merely mechanically disseminated throughout it; and, by demanding a fresh chemical process, have been inimical to the intention then in view, of mechanical suspension only, and almost instantaneous deposition. Next, we allude to the admirable adaptation of the agent employed for effecting, in the most appropriate manner, the deposition of the earthy material, which was thus sent to make a smooth and habitable soil, from a heterogeneous mass of boulders, fragments, gravel, sand, and finely comminuted earthy soil; as it must be self obvious, that according to the laws affecting them, they would be deposited from the liquid carrier in proportion to the sizes of the fragments, particles, &c., and thus the asperities would be rounded


off at the same time that the land itself was formed. Similar reasons will also explain how the more massive boulders, in many instances, would be deposited near to the site of their parent rocks, while the finer particles would be conveyed, even to within the tropics, to fill up and form the extended table lands of these regions, and constitute those almost interminable depths of light calcareous soil, which so frequently characterise those elevated plains, across whose broad and fertile surface it has so often been our lot to travel; and to view with wonder and amazement the great depth of the accumulated soil, sand, and gravel, exposed by deep ravines, and laid bare by the river courses when these were reduced to rivulets during the dry season.

It will have been observed, that in these investigations, we have taken no notice whatever of the saliferous deposits which, so generally, are associated with these widely-spread arenaceous formations; it is our intention to treat very fully of these in a subsequent part of this work, after having explained our views respecting the formation of the atmosphere, according to the Dynamical principles of this theory. Neither have we alluded in any manner to the remaining three-fourths of the earth's surface, or the part which constitutes the bed of the ocean. Over all that area, no doubt, somewhat similar events would be taking place, to those which were occurring on the terrestrial portion of the globe; but as the debris occasioned in the oceanic part would be precisely proportioned to the surface over which it was spread, the quantities being equal, in both terms of the equation, they can be eliminated, or disregarded entirely, without affecting the correctness of the general argument.





The previous subject continued. Formation of Earths and Soils. The attendant circumstances peculiarly favourable for this needful process. The unconformable rocky masses which overlie the coal measures. Geological evidence of their existence. Enquiry into their origin, as made known to us by the Dynamical Theory. Geological character of the newer Secondary Suites. The New Red Sandstone, the Oolitic, and the Cretaceous groups. Their saliferous associates reserved for a future Section. The Supra-cretaceous deposits, as explained by this Theory, and the clear line of demarcation which it draws between them and the still more recent surface accumulations, the residium of the Deluge.

To make manifest that everything was arranged by a Wisdom which is infinite, and that all the attendant circumstances were made to conspire towards the completion of the great plan of creation, then progressively and rapidly being unfolded, we shall, at this opportune juncture, direct the attention to the nature and formation of earths and soils. In doing this, we shall merely recapitulate, in succession, those Theorems which have reference to these substances. The subjects they treat of being quite of an elementary character, we do not consider it requisite to detain the general argument by bringing forward their evidences; reference may therefore be made to their respective authorities, should any doubts be entertained, or further information required on the subject. In passing, however, we may take occasion to mention, what may perhaps not be so generally known, namely-that some celebrated French chemists have discovered, and satisfactorily

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