Ch. XXII.] PROOFS OF DENUDATION. 307 



in mediately appear, that a considerable mass of chalk must 

 have been removed by denudation. 



If the anticlinal dip had been confined to the valley of 

 Kingsclere, we might have supposed that the upheaving force 

 had acted on a mere point, forcing upwards the superincumbent 

 strata into a small dome-shaped eminence, the crown of which 

 had been subsequently cut off. But Dr. Buckland traced the 

 line of opposite dip far beyond the confluence of the chalk 

 escarpments, and found that it was prolonged in a more north- 

 west direction far beyond the point a, diagram No. 78. In 

 following the line thus extended, the strata are seen in numerous 

 chalk-pits to have an opposite dip on either side of a central 

 axis, from which we may clearly infer the linear direction of the 

 movement. Perhaps the intensity of the disturbing force was 

 greatest where the denudation of the valley of Kingsclere took 

 place ; but this cannot be confidently inferred, for the quantity 

 of matter removed by aqueous agency must depend on the set 

 of the tides and currents at the period of emergence, and 

 not solely on the amount of elevation and derangement of 

 the strata. 



Many of the valleys enumerated by Dr. Buckland as having 

 a similar conformation to that of Kingsclere, run east and west, 

 like the anticlinal ridge of the Weald valley. Several of these 

 occur in Wiltshire and Dorsetshire, and they are all circum- 

 scribed by an escarpment whose component strata dip outwards 

 from an anticlinal line running along the central axis of the 

 valley. One of these, distant about seven miles to the north-east 

 of Weymouth, is nearly elliptical in shape, and in size does not 

 much exceed that of the Coliseum at Rome. Their drainage 

 is generally effected by an aperture in one of their lateral escarp- 

 ments, and not at either extremity of their longer axis, as 

 would have happened had they been simply excavated by the 

 sweeping force of rapid water*. 



'It will be seen,' continues Dr. Buckland, 'if we follow on 

 Mr. Greenough's map the south-western escarpment of the 



* Dr. Bucklaud, Geol. Trans,, 2nd Series, vol. ii. p 122. 



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