Page:A Treatise on Geology, volume 1.djvu/340

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324
A TREATISE ON GEOLOGY.
CHAP. VI.


From these short notices, the reader may be assured, that, even on the British coasts, the phenomenon of raised beaches is one of the most general yet known: that the deposits called by this name were accumulated under considerably different circumstances, is certain; their high antiquity is proved by the superposition (in general) of the erratic boulders; and the general analogies they offer to the Sicilian and other tertiary deposits are obvious and important. A philosophical study of these till lately neglected phenomena will certainly reward investigation, and probably strengthen in a high degree the basis of geological induction.

Turning to other countries, we find abundance of analogous facts. As on the south coast of England, so on the north coast of France, on the hills of St. Michel, formations of the nature above described occur, and have been described by M. Fleuriau de Bellevue and M. Brongniart, under the name of "gravier coquillier." The shells of St. Michel consist of many species, univalves and bivalves; the two pieces of the latter often remaining in their proper position; the whole retaining both their natural colour and texture, and lying as similar shells are associated at this day on the neighbouring coast Ostrea edulis, anomia ephippium, pecten sanguineus, modiola barbata, murex imbricatus, buccinum reticulatum, are mentioned as the principal species. They are placed nearly fifty feet above the sea. At Nice, similar banks occur at nearly the same elevation; the coasts of Sicily, Greece, and Asia Minor, give similar evidence.

Both on the Baltic and the Atlantic coasts of the Scandinavian peninsula, phenomena of the same nature have been long known and rendered famous by the relation they bear to the hypothesis of the gradual subsidence of the level of the Baltic. Von Buch, Brongniart, Strom, Lyell, and Forchhammer have investigated the facts with attention and success. On the western coast of Sweden, at Uddevalla in the province of Gotheburg, in a little bay of gneiss rocks, occurs so vast a quantity of shells,