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extension of these deposits, we had the evidence of a gradually 

 deepening marine area, open to the north, with land on the 

 south and west. I believed, moreover, that the Norfolk Lower 

 Glacial was a local deposit containing Scandinavian drift from 

 the N.E. and accumulated before the cold became great enough 

 to cause the formation of ice near the sea level in Britain, but 

 that as the land sank and the cold increased, bergs and coast- 

 ice from British shores supplied the detritus found in the 

 superior and wider-spread deposits. 



Messrs Wood and Harmer however have lately publislied a 

 long paper in which they discuss these questions, and put for- 

 ward two important considerations*; (1) that the Contorted 

 Drift, which they class with the Lower Glacial, had a much 

 wider southward extension than previously supposed ; (2) that a 

 marked unconformity exists between the Lower and the Middle 

 Glacial deposits, the break being of such extent and importance 

 that all the valley systems of East Anglia had their inception in 

 the intermediate period. 



Suggestive as the whole paper is, I cannot consider that the 

 evidence for either of these propositions is at all satisfactory. 

 The identification of the Suffolk brick-earths with the Contorted 

 Drift is by no means certain ; and the section mainly relied on 

 to show the unconformity between this deposit and the Middle 

 Glacial, viz. that along the coast of Norfolk, is, to say the least, 

 capable of a different interpretation. The conclusion to which 

 I came after a careful inspection of it was that the gravels 

 formed part of the contortions, and were closely connected with 

 the beds below instead of being separated from them by a 

 marked line of erosion and denudation ^ 



The last few pages of the paper are devoted to a considera- 

 tion of the mode in which the Middle and Upper Glacial beds 

 are accumulated ; the authors conjecture that a branch of the 

 ice-sheet, moving southwards from Yorkshire and Lincolnshire, 

 and being of great thickness (1200 to 1500 feet), occupied all 

 the low ground of the midland counties as far south as Bucks, 

 " in such a way that it avoided all but the extreme west of 



1 Quart. Journ. Geol. Soc. Vol. xxxtii. p. 74. 



* My colleague, Mr C. Keid, informs me tliat his survey of the Cromer coast 

 has led him to take the same view. 



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