Mr. De la Beciie on the South Coast of England. 47 



rounded masses of porphyry, from a few inches to two or three feet in dia- 

 meter : and between Teignmouth and Babbacombe Bay it contains small peb- 

 bles, of the same limestone which it rests upon at the latter place. 



It will be seen, by reference to the section, that this coast presents two strik- 

 ing examples of the almost sudden termination of strata, close to points where 

 they attain a thickness which is very considerable. At its eastern extremity, 

 the beds of the oolite formation, the thickness of which exceeds three hundred 

 feet, and which at Down Cliff are interposed between the lias and green sand, 

 entirely vanish before they reach the cliff of Golden Cap; and the lias itself, 

 Avhich is from three to four hundred feet thick between Charmouth and 

 Lyme, is, together with the oolite, totally wanting between the green sand and 

 red marl at Axmouth Point. It unfortunately happens, from the covered state 

 of the cliff to the east of this point, and the occurrence of the valley of Sea- 

 ton between Down Cliff and Golden Cap, that it is not possible to discover 

 the exact place and manner in which these formations originally terminated, — 

 whether suddenly by an abrupt escarpment in the midst of their full thickness, 

 or gradually by thinning off to the point at which they totally cease. 



The fault on the sea-shore between Ware Cliffs and Pinhay, is a case of 

 dislocation affecting the lias, similar to those which are seen to advantage at 

 the Old Passage near Bristol. 



