Page:The Cornwall coast.djvu/19

 The Cornwall Coast CHAPTER I THE PLYMOUTH DISTRICT BRITAIN is an emergent mass of land rising from a submarine platform that attaches it to the Continent of Europe. The shallowness of its waters — shallow relatively to the profundity of ocean deeps — is most pronounced off the eastern and south- eastern coasts ; but it extends westward as far as the isles of Scilly, which are isolated mountain- peaks of the submerged plateau. The seas that wash the long Cornish peninsula, therefore, though they are thoroughly oceanic in character, especially on the north, are not oceanic in depth ; we have to pass far beyond Scilly to cross the hundred-fathom line. From the Dover strait westward there is a gradual lowering of the incline, though of course with such variations and undulations as we find on the emerged plains ; but the existence of this vast submarine basis must cause us to think of our island, naturally and geologically, as a true part of the great European continent, rendered insular by the comparatively recent intrusion of shallow and narrow waters. With some developments and 13