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] which covers it near the mouth of the river Alt, at High Town. The depth to which the forest has been submerged in this district cannot be less than thirty feet. It is worthy of remark that the enormous trunks of the trees prove that the Scotch firs, oaks, yews, willows, and birches, of which the forest was in these places mainly composed, must have grown at some distance from the ancient coast-line, since the westerly winds sweeping over Lancashire from the Atlantic at the present time prevent the free growth of vegetation on every unprotected spot on the coast. The prevalent gales, however, are proved to have been very much the same as now, by the position of the trees, which lie prostrate with their heads pointing towards the east.

Evidence similar to this is to be found in the forest growths on the coasts, extending underneath the alluvium at the mouths of our rivers, as for example that of the Thames, which shows that the submergence has not been local, and that the depression of land throughout Great Britain and Ireland, since the trees flourished, could not be less than from thirty to forty feet. The ten-fathom line, therefore, considered by Sir Henry de la Beche to be roughly the boundary of the land at that time, may be taken to represent the sea margin with tolerable accuracy. In that case a considerable area would be added to the land surface of Britain, and especially of Cardigan Bay, of which the Welsh peasant still tells the story of the land swallowed by the sea; and off the coast of Lancashire and Cheshire, where the size of the submerged trees proves that they grew some distance from the sea-board; as well as off the coasts of Essex and Lincolnshire. It would include the