114 On Sand-banks. 



coming round the Mount from the east and west at every 

 tide. Three hundred years ago, Leland observed that " the 

 passage to the Mount from the main was six hours open " out 

 of the twelve — and so it continued for 220 years afterwards 

 without " the least alteration."* But within the last eighty 

 years a very sensible change has been effected ; for at pre- 

 sent the passage is open only four hours out of the twelve, 

 and frequently, at neap-tides, during the prevalence of strong 

 SW. winds, the causeway remains covered for days together. 

 This change in the period of the Mount's insulation from 

 half to two-thirds of the day, appears to be owing to the re- 

 moval of the sand that adjoined and supported the western 

 side of the ridge, which has consequently lost much of its 

 elevation, and is, therefore, covered proportionally earlier 

 every tide. Another effect produced on the causeway from 

 this removal of the sand and deepening of the water on its 

 west, is that it has been bent or shifted, near the centre, 

 many feet farther towards the east than it was forty years 

 ago. 



Some suppose that the action of the waves has been the 

 chief cause of the disappearance of our sand-banks, and 

 doubtless it has often, during storms, undermined and pros- 

 trated large portions, and carried out considerable quantities 

 of beach beyond the line of low-water ; but, in the course of 

 the year the sea always deposits on the shore much more than 

 it withdraws. The great cause of the lessening of the banks 

 appears to be the constant abstraction of the adjacent sand 

 and pebbles, between low and high water, for manure, ballast, 

 road-making, building, and other purposes. Some idea of 

 the vast quantity taken for manure may be gathered from 

 the fact, that a very usual clause in farming-leases in this 

 neighbourhood is, that ten butt-loads of sea-sand shall be 

 spread on every acre whenever it is broken for tillage ; and 

 the sand is often carted away over a hilly country to farms 

 five or six miles ^rom the coves which furnish it. The quan- 

 tity used for ballast must be also very great, as Penzance is 

 a place of considerable trade, and the exports of merchandise 



* " Natural History of St Michael's Mount, by the late ingenious Mr Price 

 of Penzance," quoted in Polwhele's Cornwall, i., p. 153. 



