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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1829 Excerpt:...at the foot of the chain, proves that they have not been excavated by the action of the rivers now flowing through them. They are evident results of diluvial waters scooping out in their retreat wide troughs among these semiindurated lands. The aggregate thickness of the upper and lower chalk is estimated by Professor Buckland at 580 feet, each of the two beds being almost equally thick. Near Dover, however, the flint-chalk is 480; that without flints is only 140; at Handfast point, the former is 600, and the latter 200 feet. In many places the total thickness is 1000 feet. In digging wells, the chalk has been frequently pierced very deeply; near Rathby in Lincolnshire, to 300 feet; in Bedfordshire, to 400; in Kent near Sittingborne, to 363; in Surrey near Dorking, to 440. But we do not know that any of these perforations have passed through the chalk. The dip of the chalk beds is in general inconsiderable. The flinty chalk forms everywhere the upper layer of this great deposit. Messrs. Cuvier and Brogniart represent the chalk deposit as forming a sterile soil; and adduce Champagne as a proof of its being in some cases uninhabitable. In our country, the population of the chalk district is less dense than that of any of the other secondary strata, but it is always habitable, and therefore productive in some degree. Dunstable Downs and Luton Downs in Bedfordshire, with the Warden White Hills, lie indeed as nature left them over a tract of 400 acres. The chalk valleys, however, are often extremely fertile; of which the Kent and Surrey hop grounds, and the Downs for pasturing sheep, afford examples. Beech is the tree best fitted for a chalky soil. The Chiltern hills in Oxfordshire, were anciently covered with thickets and woods of beech, which afforded harbour...