SAND AND PEBBLES OF THE SEASHORE 51 



of shore-lands, which face northwards. Blown sand 

 forms hills 30 feet and more in height on such flat lands 

 as those of the Sandwich and Deal " links," which have 

 been thrown up by the sea since St. Augustine landed 

 at Richborough, then a seaport, now a couple of miles 

 from the sea. On the French coast near Boulogne the 

 sand has been blown inland so as to form stratified 

 deposits on the low hill country as far as 3 or 4 miles 

 from the sea, and the neighbouring port of Ambleteuse, 

 which five hundred years ago had the chief trade with 

 England is now nothing but a vast stratified " dune " of 

 blown sand. The great Napoleon made some attempt 

 to reopen the harbour, but gave it up as a bad job ; the 

 blowing of sand inwards from the enormous tract of flat, 

 sandy shore was too much for his engineers. 



The " erosion " and the contrary process of the 

 " extension " of the coast by the action of the waves 

 and currents of the sea must be kept apart and dis- 

 tinguished from a process leading to similar but not 

 identical results, namely, the actual " crumpling " or 

 " buckling " of the earth's crust, leading to the rising of 

 the land surface in some parts of the globe relatively to 

 the sea-level, and on the other hand to the sinking of 

 the land beneath the sea in other regions. This change 

 of the actual level of the land has continually gone on in 

 the past, and is continually going on to-day. What are 

 called " raised beaches " are seen on many parts of the 

 coast. These are lines of ancient beach, consisting of 

 sea-worn pebbles, fragments of shell, etc., forming terraces 

 along the face of the rocks which rise from the present 

 seashore terraces which are now 15, 30, or more 

 feet above the sea-level, although they must at no very 

 distant period have been at the level of the sea. The 

 land has risen and carried them up out of reach of the 



