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Reports and Proceedings. 



■composed that every wind blows the sand away in clouds, and leaves 

 the shingle to rattle down upon the beach. So loose is this material 

 that that part of the coast-line which had cliffs composed of this 

 sand has now but an insignificant height ; the sand has been blown 

 away by wind and wasted by rain, until the shingle has been left 

 dropping lower and lower, and the stones which neither wind nor 

 rain could affect have come closer and closer together. This is the 

 cause of the land connecting Hengistbury Head being much lower 

 than any other in the neighbourhood. The shingly beds are ancient 

 sea-beaches, and their slope to the ancient sea can still be seen in 

 places. So long have they been exposed that the flint pebbles in 

 them are sometimes almost decomposed, the familiar white coating 

 to the flints being an inch or more thick. This shingle, which is 

 composed of rounded pebbles, that tell the tale of a long rolling on 

 the old sea-beach, is now the source of the pebbles on the present 

 beach, and the rounded condition of these pebbles on this part of 

 the coast is not, as on the shore further towards Poole, or as at 

 Brighton, the result of present wave-action, although the existing 

 sea has undoubtedly reduced the pebbles in size. They cannot be 

 confounded with the later angular river-gravels which everywhere 

 cover this area. 



At the peninsula of Hengistbury Head, about six miles beyond 

 Bournemouth, the clifis again rise, being at first composed of black, 

 chocolate-coloured, and white sands with pebbles, and farther on of 

 green clayey sands containing nodules of large irregularly-shaped 

 concretions of sandy, argillaceous ironstone disposed in layers. 

 Beyond Christchurch Harbour we have cliffs of white sand, which, 

 according to my views, close the series. 



Inland the country has a barren appearance except in the planta- 

 tions, and the scattered brick-pits afford no additional information of 

 use to us in our present researches. 



FRESHWATER 



Fig, 1. 



In the above rough diagram (Fig. 1) the lower fresh-water series 

 is seen in the neighbourhood of Corfe, and forms part of the cliffs at 

 Studland. It is marked by beds of pipe-clay, and has a thickness of 

 200 feet or more. 



Near Corfe and Studland the middle fresh-water series is met with, 

 forming the whole thickness of the cliffs between Poole Harbour and 

 Bournemouth, — the section being four miles long and 100 feet 

 higii. Their entire thickness cannot yet be accurately stated, but 

 may be put down at some 300 feet. They are characterized by the 

 fact that the clays contained in them are usually brick-earth. 



