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Reports and Proceedings. 
composed that every wind blows tlie sand away in clouds, and leaves 
the shingle to rattle down upon the beach. So loose is tbis 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 familiär white coating 
to the flints being an inch or more thick. This shingle, which is 
composed of rounded pebbles, that teil 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 ooast 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 cliffs 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 
eoncretions 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. 
F RE SH WATER. MARINE 
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 
high. 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. 
