174 GEOLOGY OF THE ISLE OF WIGHT. 



mounds of the early inhabitants of the country — 

 the coombes and furrows ramifying and extending 

 into the dee]) valleys which abruptly terminate 

 at the base of the hills, and appear like dried up 

 channels of rivulets and streams, though free from 

 all traces of alluvial debris — thus bearing the 

 impress of physical operations of which the 

 agents that produced them have long since passed 

 away — are phenomena familiar to every one 

 who has travelled over the downs of the south- 

 east of England, and are displayed in striking 

 characters in the chalk districts of the " beau- 

 tiful Island." These features are restricted to 

 the hilly districts of the white-chalk, and have 

 resulted from the peculiar nature of the sedimen- 

 tary detritus of which the strata comprised in the 

 upper division of the cretaceous system are com- 

 posed. For in the lower groups, clays, marls, 

 sands, and sandstones prevail, and where these 

 deposits approach the surface and form the sub- 

 soil, the country is broken and diversified, and 

 the landscape presents a striking contrast with 

 the down scenery ; as may be observed in the 

 picturesque district which flanks the escarpment 

 of the chalk hills. 



It may perhaps be necessary to remind the 

 unscientific observer that these strata are but 



