Page:A Treatise on Geology, volume 1.djvu/341

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CHAP. VI.
POST-TERTIARY STRATA.
325

70 metres (76 yards) above the sea, that they have from time immemorial been collected for use on foot-paths. In hollows of the gneiss rocks, M. Brongniart found balani yet adhering, and detached fragments to prove the interesting fact.

In a recent visit to Sweden, Mr. Lyell has confirmed and extended these observations, and connected the results with the general question of subterranean movements and the local speculation of the lowering of the Baltic,—an expression which may very properly be transformed into a rising of the borders of that sea. Near Stockholm, remarkable ridges of sand and gravel, called sand oasar (asar), 50 to 100 feet high, range north and south, and yield good road materials. Under one of these ridges in the same sand and gravel, 30 feet above the Baltic, are found shells in abundance, such as now live in the Baltic, viz., cardium edule, tellina Baltica, mytilus edulis, littorina crassior, l. littorea, &c. At other spots, 70, 90, 100 feet above the sea, shells in general similar to the above (with neritina fluviatilis and bulimus lubricus, a land shell) were found abundantly, about Stockholm, Upsala, and Gefle; and sometimes covered by erratic blocks (Upsala). It was noticed at Uddevalla, that several species of fusus occur there, though none are now found in the Baltic. From the whole investigation it appears certain, that both on the Atlantic and the Baltic shore, the land has in some ancient periods risen considerably (200 feet at least), so that Lake Wener on the west, and Lake Maeler on the east, were formerly parts of the ocean: it also appears probable, that a part of the Scandinavian peninsula is, at this day, gradually rising higher above the sea, but this rise does not affect the south of Scania; the rate of rise is supposed to be three feet in a century at Lofgrundet, north of Upsala.

In connection with this subject, we may mention the extended deposits of sea shells (though their identity with existing species may be doubtful) on the plains round the Caspian; the shelly sands at the Cape of