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And surely no one ought to consider such enquiries too bold for our limited faculties, needless for our present, or dangerous for our future welfare. No naturalist, desirous of knowing the truth, can be so weak as to fancy that any search into the works of God, or any contemplation of the wonders of His creation, can interfere with the lessons He has taught us in His revealed and written word."

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Before we depart from this, which may be termed the mineral group of evidences for the truth of the Dynamical Theory; and while we allude to the precision with which these evidences point to the line of demarcation between those extensively persistent rocky deposits, occasioned by the general outbreaking and upheaving commotion of the first rotation, and the finely comminuted and more tranquilly deposited earthy and clayey formations of the upper tertiaries; we must not overlook the concurring testimony as to their isolated character, which was alike deduced from their internal structure, or composition, and from their situations. These facts, which are perfectly in accordance with disintegration, occasioned by water agitated by fierce winds, and consequently acting on each locality, without being attended by progressive motion; is wholly inconsistent with the violent rush of water which was occasioned by the protorotation of the earth. While the local comminution and depositions, which seem so strongly to be evidenced by the newer tertiary rocks; and which have drawn from so many geologists the concurring opinion, that they were formed in lakes and estuaries, at mouths of rivers, and from the detritus of surrounding hills and anterior formations -an opinion more strongly and truthfully expressed by Mr. Phillips than by any of his contemporaries-is satisfactorily corroborative of a system which disowns them as the result of an impetuous onward rush of water, speedily evaporated from the high lands and dry portions; while, on the

Botany, in Cab. Cyc. pp. 310–314. Part of this quotation has been given already, but such repetitions are almost unavoidable; inasmuch as one passage, from any author, may, and not unfrequently does, afford evidence in favour of several distinct positions, each of which is sought to be established.

↑ It may be worthy of notice, that in the standard Spanish edition of the Bible, this violent "agitation" of the water is particularly mentioned, both in the text and in the notes, more especially in the latter.

other hand, it refers them to the more stationary, though not altogether tranquil subsidence of the waters of the deluge, when "God remembered Noah, and every living thing, and all the cattle that was with him in the ark: and God made a wind to pass over the earth, and the waters assuaged; the fountains also of the deep, and the windows of heaven, were stopped, and the rain from heaven was restrained; and the waters returned from off the earth continually: and after the end of the hundred and fifty days the waters were abated."*

* Genesis viii. 1-3.





Erratic block group. The importance of travelled debris in substantiating the Dynamical Theory. Geologically described, and copious evidences given respecting them. The information acquired applied to the point under discussion, and to the assumed condition of the earth, at the period of the origin of the Erratic Block Group, and found to agree most conclusively.

OUR attention is now to be directed to the last division of geological phenomena which we require to bring before our readers a class whose elucidation, by means of this hypothesis, is almost of itself capable of proving the soundness of our views. We allude to the fragments of rock, on which Sir Henry de la Beche has conferred the title of the "Erratic Block Group," a designation which will be found to be very appropriate, when the true origin and history of the debris, of which it is composed, shall have been investigated by the light of the Dynamical Theory.

A learned geologist, having occasion to allude to some of the boulders of the north of England, said, "that many of them fortunately were land-marks, and boundary stones of parishes, otherwise much of their curious history would have been lost under the hammer of the mason and of the road maker." While gladly adopting, we would likewise extend this idea, and add, that fortunately, indeed, have they been preserved, from respect to those minor offices which they now fulfil; for

* Professor Phillips, at the British Association, 1836.

they likewise perform the more important duty of pointing out to the world's inhabitants, how this pedestal, on which they are wheeled through space, received its variety of hill and dale from the hands of their common Creator! In short, they are the "land-marks" of the Dynamical Theory, and exhibit, in language which can neither be misinterpreted nor denied, that the earth, when first caused to revolve around its axis, received the form, which, in its greater outlines, it still preserves.

But let us first adduce the geological evidences, and afterwards draw the appropriate inferences. The thirty-fourth Theorem has exclusive reference to these interesting fragments, and states "That in several parts of Europe and America, immense quantities of travelled debris, gravel, and massive boulders, termed by Sir H. de la Beche "THE ERRATIC BLOCK GROUP," are found either resting on, or imbedded in the soil. That the boulders and larger debris, when they have been traced to the nearest fixed group of the same mineralogical character, are generally found to have come from a considerable distance. That those boulders in Britain, Germany, Russia, and North America, whose sites and derivations are ascertained, have been identified with mountain chains existing to the north of where they now lie; whilst those in South America seem, on the contrary, to have originated from localities southward of their present resting places. Finally, the the position of the gravel and smaller detritus appears to have been materially modified by local formations."

The evidences on which this important theorem rests, being of a very interesting character, we shall give them at considerable length:

"There are," says Professor Phillips, "geologists who would gladly expunge the word diluvial from our nomenclature, and instead of appealing to one or several general convulsions for the explanation of some striking fact, are willing to believe that small and local forces, operating through long time, are sufficient for the purpose of geological speculation. In many instances we concede to these writers, that streams wandering in any required direction, over ground indefinitely variable in level, might, in the course of unlimited time, transport detritus in directions not possible during the present or any prior statical condition of the earth's surface. But who will

grant these postulates, for the purpose of avoiding the appeal to sudden and energetic disturbances of the relative level of land and water, that has seen the enormous dislocations of the carboniferous system of South Wales and the north of England, the prodigious and extended faults in the south of England chalk; or has imagined to himself the upraising of a chain of mountains like the Alps, or witnessed the enormous conglomerates on their flanks? And if a case can be adduced so circumstanced, that those postulates must be rejected, on good geological evidence, what is to be done but to allow the alternative, namely, the occurrence of great and violent movements of large bodies of water, partial though not general deluges ?"

"The erratic blocks," continues Prof. Phillips, "as the larger boulders are called, which have been transported from the Alps, are most remarkable on the eastern face of the Jura, which looks towards the Alps, over the vale of the Arve and the lake of Geneva. On the Jura, 1,500 to 2,000 feet above the lake of Geneva, crowning the hills and filling the valleys and rocky glens, in and around the lake of Geneva and the valley of Arve, as well as along the valleys which descend from the Alps, these blocks abound. It is observed that the blocks abound opposite to the embouchures of these valleys, and that distinct sets of blocks derived from different mountains have followed the lines of the different valleys. The blocks in the valley of the Rhine have come from the Grissons; those by the lake of Zurich and the course of the Limmat were drifted from Glaris; blocks from the source of the Reuss have followed this river; the blocks of the Aar, and the slopes of the neighbouring Jura have come from the range of the Oberland of Berne. From these facts, and the circumstance that the height to which the blocks have ascended the Jura, no doubt can be entertained, that the currents flowed from these mountains in many directions, and followed the line of the present valleys. It appears the most probable view of these phenomena that a general and violent convulsion of the Alps, while they were surrounded by water (whether fresh or salt we cannot decide) caused powerful currents to rush away from the axis of movement, bearing ice rafts loaded with the loosened rocks.

"This explanation appeared satisfactory to Venturi, reasoning on the phenomena of the south side of the Alps; it has been suggested from the case of the blocks on the drainage of the St. Lawrence, and

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