BEACHES, ETC., OE THE SOUTH OE ENGLAND. 343 



beeu removed — which is not probable, as during a certain and not 

 inconsiderable part of the interval the existing level has been 

 maintained — it would involve no very long period of time. Eor we 

 have to bear in mind that, with the soft Cretaceous and Jurassic 

 strata of great part of the South Coast, 1500 to 2500 years would 

 have sufficed to wear back the clilffs for the distance of a mile. In 

 the case of the harder Palaeozoic rocks of Devon and Cornwall, the 

 wear has been singularly small, the difference between the outline 

 of the coast at the time of the Raised Beaches and that which it 

 has at the present day not exceeding 100 to 200 feet, if so much 

 (see Map, PI. YIII.). 



It would follow from this evidence that the Eaised Beaches 

 and Caves are but little removed in space or time from the 

 Alluvial beds of the Recent epoch — a conclusion which corro- 

 borates the inference I had before drawn ^ from other data, 

 that the Glacial times came, geologically speaking, to within a 

 measurable distance of our own times, and that the transition was 

 short and almost abrupt. 



I have limited this paper to the consideration of the area with 

 which I am best acquainted and in which the phenomena are well 

 defined. I reserve for the present the consideration of the extension 

 of the submergence over other areas. 



Plate VII. 



Sections illustrating the occurrence of the Raised Beaches and 'Head' or 

 Eubble-drift in the South of England. 



EXPLANATION OF MAP (PLATE VIII. ). 



The Rubble-drift. —On a Map of this scale it is not possible to give exact 

 details of the inland distribution of this drift. Therefore only a few of 

 the localities inland, where its various types are best seen, are given. 

 Where these form sufficiently distinct or fossiliferous deposits, they are 

 indicated in solid colour ; where they only form thin beds or mere trail, 

 they are indicated by bars or dots. There are, however, few areas free 

 from this drift in mass, though it is often a mere surface sprinkling. 



The Raised Beaches. — All the known Beaches are shown. Their probable 

 position on the coast, where it no longer exists, is marked by a dotted line. 

 The area so euclosed shows the extent of land removed since the period of 

 the Rubble-drift, while the area forming dry land after the uplift of the 

 Beaches is shown in light blue. 



The red bars mark the area of land lost since the Raised Beach epoch. 

 1 Quart. Journ. Geol. Soc. vol. xliii. (1887) p. 393. 



Q.J.G.S. No. 190. V 2 a 



