so C4LACIAL sECTIo^'s EorxD suDBrET. [Feb. 19 1 2, 



Thus, while I am fully couscious of the difficulties presented by the hypothesis 

 of the subaqueous deposition of Boulder Clay, that which regards it as the 

 direct product of an ice-sheet seems to me to inrolye vet more serious 

 difficulties, at any rate in our Eastern Counties.' 



The Author, in reply, agreed with Mr. Whitaker as to the 

 existence of Boulder Clays of more than one age. But the sheets 

 described in these gravels were not contemporaneous lenticles ; they 

 had tolerably uniform thickness and abrupt ends. Without the 

 aid afforded by the 6-inch maps and contour-lines, the paper could 

 not have been composed. Photographs had been taken, but these 

 materials do not readily give clear results. 



