NORFOLK-CLIFFS FOREST-BED. 197 



of which the English geologists have given important informa- 

 tion. We have already (pp. 171, 172) mentioned the ibrest-bed 

 of Cromer on the Norfolk coast, and shown that it probably be- 

 longs to the same period as the Swiss lignites. This forest was 

 situated on the sea-coast ; for the masses of fine sand and clay 

 which cover it contain animals of both fresh and brackish water 

 (Cyclas, Valvata, and Mytilus) ; above these strata is a deposit 

 consisting of unstratified masses, and containing angular polished 

 and scratched stones. Among the latter are found granite, 

 syenite, and porphyry, which, according to Lyell, have come on 

 icebergs from Scandinavia, and have been deposited there. It 

 is covered with masses of sand and rolled pebbles. They are 

 submarine glacial deposits, which here and there attain a thick- 

 ness of 400 feet, thus giving a depth to which, at the least, 

 the land must have sunk : afterwards it was upheaved. At one 

 place (near Mundesley) there is a valley formed by denudation, 

 the bottom of which consists of a bed of rolled pebbles ; and 

 upon this is a bed of peat overlain by a bed of yellow sand, 

 which has been deposited since the Glacial period. Hence it is 

 manifest that on the Norfolk coast, just as at Utznach and 

 Diiriiten, there had been a formation produced by glaciers above 

 the deposit with Elephas primigenius and the Rhinoceros, but 

 that in England this glacial formation had been connected with 

 great changes in the level of the land. 



Similar phenomena occurred in Scotland. According to 

 Lyell (Antiquity of Man, p. 241), three phases of development 

 may be distinguished. At the time of the formation of the 

 forest-bed of Cromer (contemporaneous with the Swiss lignite- 

 formation) a gradual elevation of the land took place, to the 

 height of 500 feet above the level of the sea. In Scotland large 

 glaciers were produced which have left records of their presence 

 in the polishing and scratching of the rocks, and in their mo- 

 raines still to be found in the valleys ; subsequently the land 

 sank, so that by degrees a great part of it became submerged, 

 and the only remains of Scotland, England, and Ireland con- 

 sisted of several small islands, represented at the present day by 

 the mountains. Great quantities of ice came down from the 

 north, bringing with them large masses of rocks and debris, 



