The sea is encroaching upon every part of the Cornish coast. In the memory of many persons still living, the cricketers were unable to throw a ball across the "_Western Green_," between Penzance and Newlyn,[6] which is now not many feet in breadth, and the grandfather of the present vicar of Madron is known to have received tithes from the land under the cliff of Penzance. On the northern coast we have striking instances of the sea having made similar inroads. This however is the natural result of the slow and silent depredation of the water upon the land; but at a very remote period we are assured by tradition, that a considerable part of the present bay, especially that comprehended within a line drawn from near Cuddan point on the east side, to Mousehole on the west, was land covered with wood, but which, by an awful convulsion and irruption of the sea, was suddenly swept away. "If we trace the north-west shore of the bay, from the Mount westward to Newlyn, the ebb tide leaves a large space uncovered; the sea sand is from one to two or three feet deep; and under this stratum of sand is found a black vegetable mould, full of woodland detritus, such as the branches, leaves, and nuts of coppice wood, together with the roots and trunks of forest trees of large growth. All these are manifestly indigenous; and, from the freshness and preservation of some of the remains, the inundation of sand, as well as water, must have been sudden and simultaneous; and the circumstance of ripe nuts and leaves remaining together would seem to shew that the irruption happened in the autumn, or in the beginning of winter. This vegetable substratum has been traced seaward as far as the ebb would permit, and has been found continuous and of like nature. Another proof of these shores having been suddenly visited by a tremendous catastrophe, has been afforded by the nature of the sand banks constituting the "_Eastern_," and "_Western Greens_," and which will be found to be the detritus of disintegrated granite; whereas the natural sand, which forms the bed of the sea, is altogether unlike it, being much more comminuted, different in colour, and evidently the result of pulverised clay-slate:"[7] but when did this mighty catastrophe occur, and what were its causes? These are questions which are not readily answered; the event is so buried in the depths of antiquity, that nothing certain or satisfactory can be collected concerning it; although it would appear from the concurrent testimony of Florence of Worcester,[8] and the Saxon Chronicles, that a remarkable invasion of the ocean occurred in November 1099. With respect to the causes of the phenomenon we are equally uninformed; let the geologist examine the appearance of the coast with attention, and then decide with what probability De Luc attributed the catastrophe to a subsidence of the land. It must not, however, be concealed that many geologists have questioned the