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 322 croûte du globe dans un point), we should see accordant indications of the former height of the water.

The following examples are selected to illustrate the nature of these deposits:—

On the coasts of Great Britain, phenomena of this kind have been observed in the valleys of the Forth (Boue, Maclaren) and the Clyde (Laskey), chiefly in the form of low terraces considerably above the actual flow of the tide; on the coast of Lancashire, about Preston (Gilberston); at the base of the Forest Hills, and other places in Cheshire (sir P. Egerton); near Shrewsbury; on the Mersey at Runcorn; and on Moel Tryvaen, near Caernarvon (Trimmer).

That an uplifting of the shores of the Moray Frith has taken place subsequent to its having assumed its present outline, is considered by Mr. Prestwich as proved, by the existence, in several places, of a raised beach. In Banffshire, this beach varies from six to twelve feet above the present high water level; and contains shells now inhabiting the neighbouring sea, as patelia vulgata, patelia lævis, trochus ziziphinus, littorina littorea, turbo retusus. At Gamrie, celebrated for its ichthyolites, Mr. Prestwich found, in light-coloured sands, associated with rolled gravel and dark clay beds, the following recent shells:—Astarte Scotica, tellina tenuis, buccinum undatum, natica glaucina, fusus turricola, dentalium dentalis, &c. They were extremely friable, but perfect. The deposit attains, in some places, a thickness of 250 feet, and rises to a height of 350 feet.

On Moel Tryvaen (1450 feet above the sea), the shells (buccinum, natica, turbo, Venus) were in fragments, adhering to the tongue, very much as in some tertiary deposits: they lie in sands and gravel, with granite boulders, 1000 feet above the sea, the country between them and the Menai being greatly broken, the rocks below the bed of shells worn and scratched by the drifting of the pebbly masses.

In Cheshire, the shelly gravel and sands, containing