CHESIL BEACH. 7 



departed, it seems to me probable that many of the Cretaceous 

 flints and cherts which now figure on the beach have been 

 derived directly from such denudation, and need not have been 

 accumulated in gravel beds — scarcely at least in hill gravels. 

 The same argument applies to materials derived from still 

 further westward. However, this is such a purely geological 

 question that I must not trouble the meeting of the Dorset 

 Field Club with further remarks in this connection, but hasten 

 onwards to other considerations. 



Origin of the Fleet. — It is almost impossible to speculate on 

 the physical history of the Chesil Beach without alluding to 

 what I may term a parallel phenomenon, viz., the tidal estuary 

 known as the Fleet, which interposes itself between the great 

 pebble beach, or bank, and the main land. It should be borne 

 in mind that the Chesil Beach is practically watertight owing to 

 the quantity of fine sand in the interstices of the pebbles, so 

 that the water in the Fleet is derived from the bi-diurnal tide 

 flowing through Smallmouth, and such trifling amounts of land 

 water as may flow off the surface in rainy weather. To a 

 geologist it presents a most interesting phenomenon in the fact 

 that we have here an instance of pure cliff'-edge erosion which is 

 not interfered with by the direct action of the sea. The tidal 

 currents are just strong enough to sweep away the waste 

 produced by atmospheric denudation. The relative hardness 

 or softness of the strata are, therefore, the sole determining 

 factors in the shape of the inland coast line. Thus we perceive 

 that, w^hilst the seaward coast line, formed by the beach, is 

 remarkably regular, the landward coast line is marked by a series 

 of indentations, the Fleet widening out as a rule where the 

 Oxford Clay prevails and narrowing where Corallian, or Corn- 

 brash rocks occur. I can scarcely doubt myself that the initia- 

 tion of the Fleet is subsequent to the formation of the Beach, 

 but, at any rate, it owes its present existence to that rampart of 

 pebbles, and the two phenomena are inseparably linked together. 



True Movcfucnt of the Chesil Beach. — You will be tired of facts 

 by this time, and even theories will begin to pall upon you, yet I 



