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A TREATISE ON GEOLOGY.
CHAP. X.

and green sand are here uplifted with the primary rocks; but the later marine lacustrine deposits lie level upon their slopes, and were clearly deposited from a sea which washed the base of the already elevated mountains.

The general direction of the chain from Cape Ortegal in Galicia to Cape Creuss in Catalonia, is a little south of east; but this general chain is composed of partial ridges, whose axes are parallel to one another, and directed W. N. W. and E. S. E.

This direction belongs to the disturbances of the same date in Provence, and near Nice, and is recognised in the Apennines, at least in the northern part, and in the country of Naples, and along the south shore of Sicily. The south western boundary of the Nägelflue in Switzerland appears to correspond with the Pyrenæo-Apennine line; as do likewise the Dalmatian and Croatian summits, the valleys of the Save and the Drave, the line of the Rhodopian mountains, and the ridge which crosses the straits of the Bosphorus. Similar directions seem to be traceable in Greece; and, as far as the evidence yet collected goes, the date of the elevation of all these mountains may be the same. The Carpathian range, parallel to the Dniester, falls into the same system, with a small line of granitic and sienitic rocks along the Elbe near Dresden, and the mean courses of the metallic veins of the Hartz. Finally, the well known disturbances of the strata in Sussex and Hampshire have the same age, and lie in the same parallel. Extending his views, M. De Beaumont finds some traces of the Pyrenæo-Apennine system in Africa, and Syria, in the Caucasus, and in the Ghauts of India; but the imperfect state of information concerning the geology of these countries renders the inferences concerning them far from precise.

On prolonging the Pyrenæo-Apennine circle across the Atlantic, by Hecla and Greenland, to the New World, we find it descend parallel to the Alleghanies and their northern connexions, which have determined the form of the