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POPULAR SCIENCE REVIEW. 
At Camber, near Rye, there is again sand in a like position 
as regards the present channel. The sand at Camber has blown 
partly over the rich meadows adjacent, but is now kept in its 
place by vegetation.* 
Patches of blown sand occur in many places along the coasts 
of Sussex, Hampshire, and Dorset. The most important areas 
are those at Christchurch and Poole ; in each case the sand has 
had great influence in obstructing the harbours. At Christ- 
church the dunes attain a height of 60 feet; and towards 
Bournemouth blown sand caps the cliffs up to a height of 
200 feet. There is some sand at the north end of the Isle of 
Portland, which, with the extremity of the Chesil Beach, 
would join the island to the main land, but that the sand is cut 
through by the narrow mouth of the Fleet — a tidal sheet of 
water which runs at the back of the Chesil Beach, between the 
shingle and the coast. 
The shores of Devon and Cornwall, especially the northern 
coasts, give many examples of somewhat large areas of sand- 
hills, which are known as “ greens ” or 66 towans.” The sand does 
not often reach any great height ; but Mr. Pengelly states that 
in Whitesand Bay, near the Land’s End, there is sand over the 
cliffs at about 200 feet above the sea. The blown sand of 
Cornwall is interesting from the fact that some of it was- 
accumulated when the land stood at a lower level than now; 
it often caps raised beaches which are separated by a cliff of 
rock, 30 or 40 feet high, from the modern beach. The sand 
here, both of the ancient and modern dunes, is, in great part, 
composed of finely-broken sea shells, with many land shells 
intermixed. This sand is largely employed as manure, and 
has been so used for nearly 300 years. Sir H. de la Beche 
estimated in 1836 that at least 400,000 tons of sand were 
annually carted into the interior of the country ; of this amount 
about one-fourth came from Padstow harbour alone. These 
estimates include sand recently washed up by the waves. Of 
the truly blown sand, that most recently formed is the most 
highly esteemed, this containing the largest proportion of lime. 
Sand which is considered worth carting contains from 40 to 70 
per cent of carbonate of lime. 
The Cornish blown sand is frequently consolidated into a 
stone, hard enough to serve for building purposes ; when freshly 
dug it is rather soft, but it hardens by exposure, and then 
becomes a very durable stone, f 
* The recent deposits of Romney Marsh have been fully described by- 
Mr. F. Drew, in the Memoirs of the Geological Survey, Sheet 4 ; 1804. 
t The human skeleton from Guadeloupe, which occupies so prominent a 
position in the palaeontological room of the British Museum, is embedded in 
