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establishment with water) to be 670 feet. The Upper Greensand 

 next in geological order is of very variable thickness and in 

 places absent altogether ; the Chalk may be therefore regarded as 

 here resting on the Gault of 100 feet in thickness; and this again 

 on the Lower Greensand of 250 feet. 



The several beds of the Chalk, Gault, and Lower Greensand 

 dip in a north easterly direction, and consequently are exposed in 

 geological succession on the plane of marine erosion, for a distance 

 of nine miles, from Dover westward. 



When the softer beds occur on this plane, as at East Wear 

 Bay, where the Chalk rests upon the Gault, the exposure of the 

 beds is very marked. The rainwater percolating through the 

 Chalk is retained by the Gault Clay, which, becoming plastic, is 

 no longer able to support the weight of the 500 feet of Chalk 

 resting on so insecure a foundation. The slipping of this 

 foundation brings about that picturesque ruin of the cliffs so 

 strikingly seen between Dover and Folkestone, in the part locally 

 known from its miniature lakes, hills, and valleys, as "Little 

 Switzerland." 



Where the shingle accumulates in quantity, it plays a 

 protective part by forming a beach that may defend the base of 

 the cliffs for centuries against the attack of the sea, as for instance, 

 the sea front of Dover. The surface drift of the sea caused by 

 the prevailing south-west winds, carries the shingle to the eastward; 

 this is intercepted by the groynes along the coast, and accumulates 

 on their western sides. When the Admiralty pier was built, the 

 shingle that had long formed a protecting beach to Dover, 

 gradually travelled to the eastward, and not having been replaced 

 by fresh accretions from the westward, the public gardens then in 

 front of the East Cliff, were swept away, and that part of the 

 Parade with its marine mansions threatened with destruction. 



The late disaster at Sandgate was, like most of the effects in 

 nature, not the result of one, but of several causes, among which 

 were the slippery foundation of the Atherfield Clay, and the water- 

 logged Sandgate beds. The rainfall in Kent is generally not more 

 than 1-75 inches for February, but last year, 1893, the rainfall in 

 February was 4'66 inches. The translation of the shingle from 

 the westward, according to a local report, had been intercepted by 

 the Seabrook wall and groynes, so that the natural weight and 

 protection of the shingle bank, on part of which Sandgate itself 

 stands, had been weakened or removed. The chief factors then 

 in the cause were, the unusual rainfall, the water-logged condition 

 of the Sandgate Beds, and the removal of the Shingle. 



A large ship, the Benvenue, had been wrecked the previous 

 autumn, and this wreck had been removed by firing heavy charges 



