l'-22 Uev. W. D. Coiiybeare o?j M. de Beaumont's Theory 



of the new red sandstone; for the general line (N.E. S.W.) 

 above hidicated, may be more correctly described as a curve 

 running nearly N. and S. in the northern part of its course, 

 and trending towards an E. and W. direction towards the 

 South ; and in like manner we find the carbonifei-ous lines 

 of elevation generally ranging N. and S. in our northern 

 counties, and E. and W. in the southern. But independently 

 of this general elevation, we find in the southern counties 

 three parallel lines of elevation ranging E. and W., and indi- 

 cative of more abrupt and violent action, which appears to 

 have occurred during the tertiary epoch, and which may very 

 probably be regarded as strictly contemporaneous. The first 

 and most important of these lines of disturbance, is that which 

 having traversed the Isle of Wight, strikes and ranges through 

 the peninsula of Purbeck, and then produces the anticlinal 

 line and parallel faults of the Weymouth district; thus ex- 

 tending over more than sixty miles. It must have produced an 

 angular movement of the strata of many thousand feet, as it 

 has thrown the chalk, plastic clay, and London clay into a 

 vertical position. The section in Alum Bay distinctly exhibit- 

 ing the contact of the disturbed and undistui'bed strata, shows 

 this derangement to have been effected by a single and most 

 violent convulsion, of which the aera is most distinctly marked 

 and precisely limited, being subsequent to the formation of 

 London clay, and anterior to the alternations of fluviatile and 

 marine deposits which characterize the basins of the Isle of 

 Wight and Paris. 



II. The anticlinal line of the Weald of Kent and Sussex, 

 ranging from the North of Hastings to the North of Petersfield. 

 — This is the cause of the elevation of the north and south 

 chalky downs, and its disturbing effects may be most strongly 

 traced in the narrow chalky ridge of the Hogsback (in the 

 former), where the strata are considerably inclined : it may very 

 probably be referred to the same Eera as the foregoing line of 

 disturbance, to which it is very nearly parallel. We may consi- 

 der this anticlinal line as prolonged through the chalk by Win- 

 chester, and a little north of Salisbury, and thus reaching the 

 Vale of Wardour, which is what Professor Buckland terms a 

 Valley of Elevation : here the Portland limestone is thrown 

 up, and the strata often considerably inclined. On the whole, 

 however, the line now described is rather an anticlinal line of 

 very gentle curvature, than one indicating violent disturbance. 

 It is impossible to dismiss this line without observing how ex- 

 actly parallel it is to the much older lines of elevation of the 

 transition strata of the Quantock Hills and the Forest of 



