DESTRUCTIVE EFFECTS OF WAVES. 29 
still farther from 30 to 120 feet. A block nine feet two inches 
by six feet and a half, and four feet thick, was hurried up the 
acclivity to a distance of 150 feet.” 
The great storm of 1824, which carried away part of the 
breakwater at Plymouth, lifted huge masses of rock, from two 
to five tons in weight, from the bottom of the weatherside and 
rolled them fairly to the top of the pile. One block of lime- 
stone weighing seven tons was washed round the western ex- 
tremity of the breakwater, and swept to a distance of 150 feet. 
In 1807, during the erection of the Bell Rock lighthouse, six 
large blocks of granite which had been landed on the reef were 
removed by the force of the sea and thrown over a rising 
ledge to the distance of twelve or fifteen paces, and an anchor 
weighing about twenty-two hundredweight was cast upon the 
surface of the rock. 
With such examples before our eyes, we cannot wonder that 
in the course of centuries all shores exposed to the full shock 
of the waves, lashing against them with every returning tide, 
should gradually be wasted and worn away. One kind of stone 
stands the brunt of the elements longer than another, but 
ultimately even the hardest rock must yield to the rage of the 
billows, which when provoked by wintry gales, batter against 
them with all the force of artillery. 
Thus, all along our coasts we find innumerable instances of 
their destructive power. Tynemouth Castle now overhangs the 
sea, although formerly separated from it by a strip of land, and 
in the old maps of Yorkshire we find spots, now sandbanks in 
the sea, marked as the ancient sites of the towns and villages 
of Auburn, Hartburn, and Hyde. The cliffs of Norfolk and 
Suffolk are subject to incessant and rapid decay. At Sherring- 
ham, Sir Charles Lyell ascertained, in 1829, some facts which 
throw light on the rate at which the sea gains upon the land. 
There was then a depth of twenty feet (sufficient to float a 
frigate) at one point in the harbour of that port, where only 
forty-eight years ago there stood a cliff fifty feet high with 
houses upon it! “If once in half a century,” remarks the great 
geologist, “ an equal amount of change were produced suddenly 
by the momentary shock of an earthquake, history would be 
filled with records of such wonderful revolutions of the earth’s 
surface ; but if the conversion of high land into deep sea be 
