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Show 344 RELATIVE ANTIQUITY [Ch, XXIV, notwithstanding the horizontality of the tertiary formations of that age. In order to illustrate the grave objections above advanced, which are aimed at the validity of the whole of de Beaumont's reasoning, let the reader suppose, that in some country three styles of architecture had prevailed in succession, each for a period of 1000 years ; £rst the Greek, then the Roman, and then the Gothic ; and that a tremendous earthquake was known to have occurred in the same district during some part of the three periods,-a shock of such violence as to have levelled to the ground every building. If an antiquary, desirous of dis-covcrinO' the date of the catastrophe, should £rst arrive at a 0 city where several Greek temples were lying in ruins and half cngul phed in the earth, while many Gothic edifices were standing uninjured, could he determine on these data the era of the shock? Certainly not. He could merely affirm that it happened at some period after the introduction of the Greek style, and before the Gothic had fallen into disuse. Should he pretend to define the date of the convulsion with greater precision, and decide that the earthquake must have occurred in the interval between the Greek and Gothic periods, that is to say, when the Roman style was in use, the fallacy in his reasoning would be too palpable to escape detection for a moment. y ct such is the 11ature. of the erroneous induction which we arc now exposing. For, in the example · above proposed, the erection of a particular edi£ce is not more distinct from the period of architecture in which it may have been raised, than is the deposition of chalk, or any other set of stl:ata, from the geological epoch to which they may belong • . Yet, if on these grounds we are compelled to include in the interval in . which the elevation of each chain may have happened, the periods of those two classes of formations before alluded to, the dei·anged and the horizontal, it follows that, even if all the facts appealed to by de Beaumont are correct, his intervals are. of indefini~e extent. He is not even warranted in asserting that the cham Ch. XXIV.] OF MOVNTAIN-CUAINS. 345 A (p. 340) is older than B (p. 341 ), if he means that it was elevated at a different geological period, for both may have been upheaved during the same period, namely, that when the strata c were formed. Supposed parallelism of contemporaneous lines of elevation.So, also, when he infers that two chains were simultaneously upraised, the proof fails, since the close of the period of the disturbed strata and the commencement of the era of the undisturbed must be added to the lapse of time during which the two chains may have originated, and in separate parts of which each may have been produced. With the insufficiency of the above evidence the whole force of the argument in support of the parallelism of lines of contemporaneous movement is annihilated. This hypothesis, indeed, of parallelism appears, even as stated by the author, in some degree at variance with itself. When certain European chains had been assumed to have been raised at the same time on the data already impugned, it was found that several of these contemporaneous chains had a parallel direction. Hence it was presumed to be a general law in geological dynamics that the chains upheaved at the same time are parallel. For example, it was said that the Pyrenees and other coetaneous chains, such as the northern Apennines, have a direction about W. N. W. and E. S. E., and to this line the Alleghanies in North America conform, as also the ghauts of Malabar, and certain chains in Egypt, Syria, northern Africa, and other countries; and from this mere conformity in direction it was presumed that all these mountain-ranges we~e thrown up simultaneously. To select another example, the principal chain of the Alps, differing in age and direction from the Pyrenees, is parallel to the Sierra Morena, the Balkan, the chain of Mount Atlas, the central chain of the Caucasus, and the Himalaya. All these ridges, therefore, were probably heaved up by the same paroxysmal convulsion ! The western Alps, on the other hand, rose at a still earlier period, wh~n the parallel chains of KiOl, in Scan- |