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 GEOLOGY The sections of the Carnon stream works in the valley which opens from the head of Restronguet Creek, as described by Mr. Edward Smith in 1817, and by Mr. Henwood some twenty-five years later, confirm the evidence at Pentuan of the burial of forest growths beneath the level of the sea. Moreover both these observers record the occurrence of human skulls, together with animal remains, principally of the deer, at a depth of over 50 feet beneath the surface. Sir Henry De la Beche mentions also that ' at Pentuan human skulls are stated to have been found under about 40 feet of detrital accumulations, also mingled with the remains of deer, oxen, hogs and whales.' Assuming therefore that the forest bed noted at Pentuan 52^ feet below the surface corresponds to the similar deposit at Carnon, with human skulls 53 feet beneath the surface, then, as Sir H. De la Beche has pointed out, ' a considerable change took place in the relative levels of sea and land since man inhabited Cornwall, allowing estuary or marine deposits to be effected in creeks upon a surface that previously permitted the growth of terrestrial vegetation, the remains of the marine creatures entombed in the mud, silt, or sand, showing that these creatures were of the same species as those which now exist in the adjoining sea.' The ancient beaches which fringe the Cornish coast were laid down in the Pleistocene seas, and now form ledges extending from only a few feet above the present sea level to a height of 65 feet. A beach at the latter elevation, according to Mr. Clement Reid, ' the highest raised beach yet discovered in Cornwall,' is seen in Penlee quarry, near Newlyn, where coarse beach-shingle rests on a rocky shelf 65 feet above ordnance datum. The old cliff and beach can be traced at about this level through Penzance, and sweeping round Mounts Bay behind the marshes.' Among the more noteworthy of these beaches are those which occur near Newquay and Godrevy, at St. Ives, Cape Cornwall, Coverack Cove, Falmouth Bay and Gerrans Bay. So long ago as 1758 Borlase de- scribed the deposit south of Cape Cornwall, although it is not actually certain that he grasped its significance to the extent of recognizing it as an ancient beach. In 1828 Mr. Carne indicated their occurrence at various localities along the cliffs of western Cornwall. In 1832 Mr. R. W. Fox, F.R.S., described the raised beaches of Falmouth Bay, as forming a bed of rounded quartz pebbles, gravel and sand, resembling that of the present coast, and from 9 to 1 2 feet above high water mark. 1 In the same year their frequent occurrence along the Cornish coast was noticed by Dr. Boase, who considered that in maximum height they did not exceed 50 feet above sea level, and sloped from that point beneath the sea just as our present shore does. ' Thus also,' he observes, ' the beds of gravel and sand at Fistral and Gerrans Bay, and elsewhere, exhibit the same phenomena, the lower part of these sometimes touching the waves, and at others appearing on the cliffs resting on the rock far above the present sea-level.' 3 These raised beaches, composed of material identical with that of 1 Trout. Geol. Soc. of Cornwall, iv. 468. * Phil. Mag. and Journal of Science, Dec. 1832.