288 SANGATTE CLIFF. [Ch. XIX. 



To explain this section ^Ye must suppose tliat, after the excavation of 

 the chff A, the beach of sand and shingle h was formed by the long- 

 continued action of the sea. The presence of Littorina littorea and 

 other recent littoral shells determines the modern date of the accumu- 

 lation. The overl^'ing beds are composed of such calcareous rubble and 

 flints, rudely stratified, as are often conspicuous in parts of the Norfolk 

 coast, where they are associated with glacial drift, and were probably of 

 contemporaneous origin. Similar flints and chalk-rubble have been re- 

 cently traced by Sir Roderick Murchison to Folkestone and along the 

 face of the cliffs at Dover, where the teeth of the fossil elephant have 

 been detected. 



Mr. Prestwich also has shown that at Sangatte, near Calais, on the 

 coast exactly opposite Dover, a similar waterworn teach, with an incum- 

 bent mass of angular flint-breccia, is visible. I have myself visited this 

 spot and found the deposit strictly analogous to that of Brighton. The 

 fundamental ancient beach has been uplifted more than 10 feet above its 

 original level. The flint-pebbles in it have evidently been rounded at the 

 base of an ancient chalk-cliff', the course of which can still be traced in- 

 land, nearly parallel with the present shore, but with a space intervening 

 between them of about one-third of a mile in its greatest breadth. This 

 space is occupied by a terrace, 100 feet in its greatest height, the com- 

 ponent materials of which are too varied and complex to be described 

 here. They are such as might, I conceive, have been heaped up above 

 the sea-level in the delta of a river draining a region of white chalk. The 

 delta may perhaps have been slowly subsiding while the strata accumu- 

 lated. Some of the beds of chalk-rubble with broken flints appear to 

 have had channels cut in them before the uppermost deposit of sand and 

 loam was thrown down. The angularity of the flints, as <Mr. Prestwich 

 has suggested, may be owing to their having been previously shattered 

 when in the body of the chalk itself ; for we often see flints so fractured 

 in situ in the chalk, especially when the latter has been much disturbed. 

 The presence also in this Sangatte drift of large fragments of angular 

 white chalk, some of them two feet in diameter, should be mentioned. 

 They are confusedly mixed with smaller gravel and fine mud, for the 

 most part devoid of stratification, and yet often too far from the old cliffs 

 to have been a talus. I therefore suspect that the waters of the river 

 and its tributaries were occasionally frozen over, and that during floods 

 the carrying power of ice co-operated with that of water to transport 

 fragile rocks and angular flints, leaving them unsorted when the ice 

 melted, or not arranged according to size and weight as in deposits 

 stratified by moving water. A climate like that now prevailing on the 

 borders of the Baltic or in Canada might produce such effects long 

 after the intense cold of the glacial epoch had passed away. The abun- 

 dance of mammalia in countries where rivers are liable to be annually 

 encumbered with ice, is a fact with which we are famihar in the northern 

 hemisphere, and the frequency of fossil remains of quadrupeds in forma- 

 tions of glacial origin ought not to excite siu'prise. As to the angulai'ily 



