Correspondence. 479 



BOULDER-CLAY AND DRIFT OF NORFOLK AND SUFFOLK, AND 

 ON THE NORTH SIDE OF THE THAMES VALLEY. 



To the Editor of the Geot.ogioal Magazine. 



Sib, — It is a pity that Mr. Maw should mix up doubts as to the 

 age of the Boulder-clay capping Gorton Cliff with those as to the 

 age of the Cromer beds. If there is one question connected Avith 

 the Drift free from doubt, it is the identity of the capping clay of 

 Corton with the Boulder-clay of High Suffolk ; and no one would, I 

 feel sure, be more ready to admit this than Mr. Maw himself, if he 

 examined the country between Corton and High Suffolk. With the 

 beds of the Cromer coast, however, the case is quite the reverse ; 

 for the features displayed by the north and north -east of Norfolk 

 are so excessively perplexing, that I should desire to pay respect to 

 the views of any one as to the structure of this part, however much 

 they differed from what I believed to be the truth, and especially to 

 those of so courteous an opponent as Mr. Maw ; but that gentleman 

 does not seem to be aware that the physical formation of the country, 

 apart from any geological question, is entirely at variance with the 

 diagram illustrating his paper, — the whole of the land between the 

 Boulder-clay country of High Norfolk and Suffolk, and Cromer, 

 being (except where the valleys of the Yare and Bure cut through 

 it) one continuous table land : and, although the elevations are not 

 given in the map, the country behind Cromer and Sherringham 

 cannot, I imagine, be any lower than the High Suffolk country from 

 which Mr. Maw starts in his diagram. Another error of fact into 

 which he has fallen is that of confounding my views with those of 

 Mr. Gunn. The red loam at the base of Corton Cliff, which Mr, 

 Gunn calls the " Lower Boulder-clay," and identifies with the 

 Cromer Till, I regard as the mud deposit overlying that Till called 

 by Sir Charles Lyell the " contorted drift." Mr. Gunn finds his 

 Upper and Lower Boulder-clays in the Cromer and Hasboro' cliff 

 sections, whereas I do not recognize any portion of the Upper 

 Glacial (and but very little of the base of the Middle) along the 

 whole twenty miles line of cliff from Hasboro' to Weybourne. Mr. 

 Gunn further seems disposed to identify his " laminated beds" with 

 the Chillesford-clay, whereas I cannot discover their geological 

 existence, and regard them as only the easterly modification of the 

 Weybourne sand. Immediately xipon the distribution (in July, 

 1865) of my small map of the East of England Drift, and remarks 

 in explanation, Mr. Harmer, of Norwich, took up the task of map- 

 ping geologically the beds from the Crag upwards in the Ordnance 

 sheets of that part of Norfolk which contain the principal drift 

 deposits. Much time must of course elapse before such a labour can 

 be completed, or even put in an intelligible shape, although I hope 

 nothing may prevent his eventually doing so. I mention this 

 because, having been furnished with all his results as he has pro- 

 ceeded, and visited with him from time to time all the sections of 

 importance met with, nothing has yet transpired from them to show 

 that the views of structure adopted by me are in any material 



