356 THE PLEISTOCENE PERIOD. 



England beds o£ sand, which I have just described other 

 than the black band, that denote a dry land surface. These 

 are to be found here between the Yrangue brickfield and the 

 newly opened road. A thick deposit of sand was exposed 

 over the 25 feet beach, which runs along the rise of land from 

 the First Tower to the Coutanchez, that belongs to the time 

 of the beach. Also on the East coast, under the cliffs, there 

 are patches of blown sand between the 25 feet beach and 

 the Head. 



In England, especially along the coasts of Cornwall (see 

 Prestwich, op. cit.), exist equivalent sand deposits of consi- 

 derable thickness. 



Of one thing we may feel confident, that is that the black 

 band is evidence that the elevation of the land was temporary 

 only, but long enough to permit of the. growth of vegetation. 

 This is only evidence of the land surface which rested on the 

 ledge of the beach which was enormously more extensive than 

 now, but as so far the land higher up had not been submerged 

 by the 25 feet level of the sea the evidence of the temporary 

 rise is confined to the margin of that sea. 



I associate the Sark Caves with sunken floors with this 

 rise of the land, at all events as far as their floors are 

 concerned. 



The 50 feet level was the sea's next stopping place. Of 

 this we may feel assured, for there are no extensive beaches, 

 nor are there any well-marked platforms ; but there are 

 intermediate deposits of beach stones in both islands, which, 

 I think, points to a successive rise of the sea-level. 



At the 50 feet level the conditions change, for not only do 

 we find well formed and extensive beaches, but the rock 

 platforms in Jersey and in the South of England denote a 

 long rest at this level. 



In Guernsey we have no visible platforms, possibly 

 because they are covered, but we have slopes already referred 

 to which connected the two levels of 25 feet and 50 feet 

 which, I think, can only be the result of the sea at the level 

 of 50 feet. These are extensive on all the marginal low 

 lands, inland, and in some places, as on the Dos d'Ane Road 

 (lower level), there are patches of pebbles brought to light in 

 well-digging. 



This is the second " point of stability," and is worthy of 

 future study. (See Diagram No. 1.) 



As the sea rose still further~the higher portions of the last 

 beach were deposited and patches of 60 feet to 75 feet occur. 

 Although I show in Guernsey a fairly marked level of 75 feet 



