64 Sir II. II. Howorth— Destruction of the Chalk. 



aware of this conformity, and gave illustrations of it, mentioned the 

 mixture of Chalk and Boulder-clay on the foreshore, and considered 

 that the contortion must clearly have been formed subsequently to 

 the deposition of the Drift" (Geology of Cromer, etc., p. 95). Again, 

 the same author says: "The Boulder-clay under the folded Chalk 

 is certainly connected with the contortion, as is also the case with 

 the alternations and intrusive tongues of Boulder-clay seen on the 



foreshore The contortion of the Chalk appears to have 



forced it into the overlying beds and compelled the boulder-clay to 

 mould itself to all hollows and open fissures ; it has even in some 

 places caused the Drift to underlie in mass the inverted anticlinal of 

 the solid chalk." 



With these facts before us, it seems impossible to doubt the con- 

 clusions of Mr. H. B. Woodward and Mr. C. Reid, as related by them 

 in the following words. The former says : " I have come to the 

 conclusion that many of the contortions seen in the strata, whether 

 Chalk, Crag or Lower Glacial, are chiefly due to the agent that 

 brought the Boulder-clay ; of the numerous cases where this positive 

 evidence is wanting I know of no instance where the contortion 

 might not have been produced at this period " (Geol. of Norwich, 

 p. 137). The latter says: "The general structure of Norfolk and 

 Suffolk appears to show that the whole of the contortions are of one 

 age, that of the greatest glaciation, or of the great chalky Boulder- 

 clay, and it is probably to this period that the disturbances on the 

 coast may be referred" (Geol. of Cromer, p. 117). 



While this conclusion seems inevitable, I cannot concede, even 

 as a possibility, that these contortions have been caused by ice in 

 any form. These contortions are, in fact, only subsidiary folds in 

 the much larger folds which formed the plateau of East Anglia and 

 the adjoining troughs on either hand, and seem unmistakably due 

 to the operation of forces acting from below, or by earth -waves 

 passing laterally thi-ough the strata as waves pass through the sea. 



The only reason given by the opponents of these subterranean 

 causes is, that the surface layers are alone contorted and puckered, 

 while the deeper ones are not. It is forgotten that this very fact 

 is most difficult, if not impossible, to explain by an ice theory, while, 

 if the contortions are eventually due to the crumpling up of the strata, 

 it will certainly follow that the highest layers will be under the 

 greatest tension ; but I have a notion that these folds are really 

 the result of gigantic earth-waves, caused by some tremendous 

 strain ; and it will be remembered that in marine waves it is only 

 the surface layers that are afi'ected at all ; at a very little below 

 the surface the water is quiescent and still. 



If we conclude that the disintegration of the Chalk was the result 

 of subterranean movements, the next question is, When did this 

 occur ? 



It seems to me impossible to cany back the breaking up of the 

 Chalk strata to Tertiary times. If it had been in progress then 

 in anything at all like the way in which we must postulate it to 

 have occurred, if we are to judge by the lumps of chalk in the 



