CHAP. xii. MUNDESLEY FRESHWATER FORMATION. 223 



and those afterwards thrown down above, may be perfectly 

 horizontal (see above). 



In most cases where the principal contortions of the layers 

 of gravel and sand have a decided correspondence with deep 

 indentations in the underlying till, the hypothesis of the 

 melting of Jarge lumps and masses of ice once mixed up with 

 the till affords the most natural explanation of the phenomena. 

 The quantity of ice now seen in the cliffs near Behring's 

 Straits, in which the remains of fossil elephants are common, 

 and the huge fragments of solid ice which Meyendorf dis 

 covered in Siberia, after piercing through a considerable 

 thickness of incumbent soil, free from ice, is in favour of 

 such an hypothesis, the partial failure of support necessarily 

 giving rise to foldings in the overlying and previously hori 

 zontal layers, as in the case of creeps in coal mines.* 



In the diagram of the cliffs at p. 213, the bent and con 

 torted beds No. 5, last alluded to, are represented as covered 

 by undisturbed beds of gravel and sand, No. 6. These are 

 usually destitute of organic remains ; but at some points 

 marine shells of recent species are said to have been found in 

 them. They afford evidence at many points of repeated 

 denudation and redeposition, and may be the monuments of 

 a long series of ages. 



Mundesley Post-glacial Freshwater Formation. 



In the range of cliffs above described at Mundesley, about 

 two miles south-east of Cromer, a fine example is seen of a 

 freshwater formation, newer than all those already mentioned, 

 a deposit which has filled up a depression hollowed out of all 

 the older beds 3, 4, and 5, of the section, p. 213. 



When I examined this line of coast in 1839, the section 

 alluded to was not so clearly laid open to view as it has 



* See Manual of Geology, by the author, p. 51. 



