﻿1861.] 



PRESTWICH BOEXDER-CLAT. 



453 



for the line of water-level was reached at a foot or two below the 

 level of the pit. Boring was then tried, when, owing to the variable 

 and often very coarse structure of the gravel, the first workmen gave 

 it up in despair. It was resumed again at a later period with the 

 obliging assistance of Mr. Monkman, the manager of the Holderness 

 Line, whose property the pit is. We had hoped to find the base of 

 the gravel at a depth of 10 to 12 feet ; whereas after penetrating 

 with difficulty to a depth of 36 feet, always in the gravel, but the 

 lower bed more argillaceous, the work had to be abandoned. These 

 borings at Kelsey Hill gave : — 



Boring at Kelsey Hill. 



r, , f Sand and gravel with shells 4 feet 



Commencing at the I j^rger gravel 16 „ 



base of ti* section Sm | llei f gravel 8 ]] 



shown at p. ( Larger gravel m grey loam (Boulder-clay?) _8 „ 



36 „ 



I may observe, that although we failed to obtain the desired 

 exact proof at this spot, yet at places close adjacent, and on the same 

 level, artesian wells have been sunk which invariably pass through a 

 greater or lesser mass of Boulder-clay before reaching the water- 

 bearing beds of sand or the chalk*. 



Attention was now turned to Paull Cliff, to ascertain whether or 

 not the clay exposed at the base of the cliff belongs to the Boulder- 

 clay. Such, proves to be the case ; for in digging below the base of 

 the cliff, Mr. Smith soon found the clay to become stony, and the 

 specimens he has sent me have the ordinary aspect of the Boulder- 

 clay. 



Section at Paull Cliff. 



(Soil and silty gravel 8 feet. 



Sand and gravel with shells 12 „ 

 Sandy dark-coloured clay without ) „ 



stones J " 



^5KS«& } - th *« aw*-** ' 



Looking therefore at all the conditions of the case, I feel satisfied 

 that these gravels with the Cyrena fluminalis overlie the great mass 

 of Boulder-clay of Holderness. The question then arises as to whe- 

 ther these shelly gravels belong to the Boulder-clay, or whether they 

 are separable from it ; and on this point the evidence is not quite 

 clear, although I am now more inclined than at first to consider it 

 tolerably conclusive. As observed by Prof. Phillips, there are places 

 on the coast where patches of sand and gravel are seen intercalated 

 in the clay, whilst inland the gravels form isolated hills, and the 



* At Hull the section of a well given by Professor Phillips shows a clearer 

 separation of the beds, these being — 



Alluvial accumulations 32 feet. 



Boulder-clay 36 „ 



Sand 26 „ 



Chalk ._16 „ 



110 „ 



