﻿The Chalk and Drift in Moen. 169 



the present, with similar clefts and furrows in the cliffs, which 

 were covered in Glacial times with a mantle of Drift now in course 

 of removal by denudation, explains every variety of Drift-inclusion. 

 These varieties are described, and proofs are given of such an over- 

 lying mantle of Drift, even now over 100 feet thick on the flanks 

 of the hills, and rising to their summits. 



Differences from the Riigen phenomena are noted and explained. 

 An apparent upward succession of Boulder-Clay, shingle-beds, sand, 

 and scattered boulders is discussed. 



Slopes of uniform inclination which rise from the beach, often 

 60 feet and more, to the bases of the vertical cliffs, appear to be 

 talus-slopes. In reality they are everywhere solid Chalk, with only 

 a skin of debris : this suggests post-Glacial changes in sea-level. 



Certain weathered-out hollows in cliff-faces indicate a way in 

 which isolated portions of Drift might, when denudation had com- 

 menced, be long protected from destruction. 



One instance of a Chalk-boulder included in Drift emphasizes the 

 general contrast, not likeness, between Mben and Cromer. The 

 position of the Drift in Moen is similar to that of the Boulder- 

 Clays at Flamborough and along the Yorkshire coast. Had the 

 Yorkshire Chalk been dislocated as that at Swanage or Luiworth, 

 probably we should have in England similarities to Mben. 



2. ' On the Relations of the Chalk and Boulder-Clav near 

 Royston (Hertfordshire)/ By Prof. T. G. Bonnev, Sc.D., LL.D., 

 F.R.S., F.G.S. 



On the uplands south of Royston, Mr. H. B. Woodward, F.R.S., 

 has described three sections, which in his opinion indicate that a 

 great ice-sheet, as it advanced from the north, sheared off large 

 masses of Chalk and mixed them up with its ground- or englacial 

 moraine (the Chalky Boulder-Clay). 



The author points out that this interpretation rests on an 

 hypothesis — namely, that the latter deposit is the direct product of 

 land-ice — which, as it involves some serious difficulties, cannot yet 

 be taken for granted. For instance, this clay in many parts of 

 England contains chalk-pebbles, more or less well-rounded, and 

 often striated. But it is improbable that fragments of rock in 

 either a ground- or an englacial moraine would be shaped into 

 ordinary pebbles ; and they would be brought into contact so 

 seldom, and for so brief a time, that they would be but little 

 scratched. But these chalk-pebbles resemble those formed by 

 water, either in a river-bed or (more probably) on a sea-beach. 

 How, in the latter case, they could be striated Col. H. "W. Feilden 

 showed twenty-eight years ago, 



That ice is capable of shearing off and thrusting before it large 

 masses of rock, is also an hypothesis, for which the author, after 

 doing his best to study ice-work in the field, can find no valid 

 evidence. He maintains that these sections do not suggest the 



