SECTIONAL TRANSACTIONS.— H. 381 



so far as East Anglia was concerned, bj' an important period of ice-recession, possibly 

 the most important experienced by the British area as regards length of time and 

 amelioration of climate. This recession was succeeded by a re-advance of ice which 

 had passed over very different rocks. 



At the moment I see only two alternative ways of avoiding the impasse referred 

 to above: (1) to regard the Cromer Forest Bed implements as older than Early 

 Chellean, notwithstanding the fact that the Cromer Forest Bed fauna contains 

 abundantly mammalian forms which accompany the Chellean industry passim, or 

 (2) to assume a certain degree of contemporaneity in ice-retreat and advance as out- 

 lined in the following paragraph. 



The Scandinavian ice-sheet is known to have hemmed in the British ice-sheet on 

 the coasts of Durham and Yorkshire ; the ice-sheets were, therefore, contemporaneous 

 so far as that area was concerned. At the same time, tlie Scandinavian ice (which 

 had possibly reached Norfolk before it reached Yorkshire) had begun to retreat from 

 Norfolk and Suffolk, allowing the valley-systems to be carved out in the interval 

 before the British ice had tinie to advance from Yorkshire over East Anglia. Thus, 

 the Scandinavian Drift and the (Lower) Chalky Boulder Clay would be pene- 

 contemporaneous and the list of glaciations in the above table would be reduced by 

 one. The difficulty of the considerable time-interval required for valley-erosion and 

 the weathering of the Norwich brickearth within a glacial epi.<iode would still remain. 



It is doubtful whether geologists would accept the second alternative. If, then, 

 there is doubt about the Chellean age of the Cromer Forest Bed implements, and if 

 the true Chellean industry should be found in the deposits which intervene between 

 the Scandinavian Drift and the Lower Chalky Boulder C^ay, the difficulty of the 

 additional glacial episode would disappear, and the Scandinavian Drift would mark 

 the first glacial episode in the British area. As the later East Anglian ' Crags ' cannot 

 be regarded as deposits of arctic character, and yield no evidence in themselves for 

 correlation with a Giinz glaciation,such a solution would probably commend itself to 

 geologists. 



Mr. J. D. Solomon considered that it is doubtful whether the Alpine sequence of 

 glaciations as developed by Penck and Briickner is applicable to East Anglia ; and, 

 indeed, the contortion of the glacial deposits and the paucity of good exposures make 

 it difficult to work out any sequence at all in the deposits. 



There are, however, certain pieces of evidence which yield good indications of the 

 relations between the glaciations and the successive Palaeolithic cultures of this area. 

 These may be briefly enumerated as follows : — 



(i) At Hoxne, in Suffolk, an Acheulean Culture is found in deposits lying between 

 a lower, chalky-Kimmeridgic boulder clay and an upper Chalky boulder clay. 



(ii) At Whitlingham, near Norwich, a mixture of unrolled or slightly rolled 

 Acheulean implements together with some rolled and glacially striated Chellean 

 implements is found in what appears to be a river-terrace gravel, which is overlain 

 by a small thickness of what appears to be a boulder clay. 



(iii) In the latest gravels of the Cromer Morainic ridge, implements of late 

 Acheulean date have been found ; and the striking glacial topography of the Cromer 

 district cannot be dissociated from the formation of the ridge and of those gravels. 



(iv) Throughout the South-easterly part of Norfolk a tripartite glacial succession 

 is known, viz. : — 



(3) Clialky Kimmeridgic boulder clay, fresh and little weathered. 



(2) Mid-giacial sands and gravels (Marine). 



(1) Norwich Brickearth, with Scandinavian boulders, much weathered. This 

 evidence bespeaks at least a tripartite glaciation in South Norfolk and North Suffolk, 

 as the Norwich Brickearth plainly represents an older glaciation than either of the 

 Hoxne boulder clays between which the Acheulean industry is found. 



But considerable difficulty arises ^\ hen an attempt is made to trace this threefold 

 division northwards into the Cromer district ; for there is here no obvious representative 

 of the Norwich Brickearth, the Cromer Till, relatively unweathered, resting directly 

 on the upper members of the Forest Bed series. However, in the cliff-section between 

 Sheringham and Mundesley there are many patches of weathered boulder clay 

 incorporated in the contorted drift, as well as patches of sand with marine fossils ; 

 and it would seem that these may quite possibly represent the Brickearth and Mid- 

 Glacial sands of further South. When the cliff-section is traced East of Mundesley, 

 the glacial deposits thin out considerably, and two layers of fresh boulder clay 



