﻿1861.] 



PEESTWICH — BOULDER-CLAY. 



455 



Section of two Borings* near Hedon, six miles from Hull and about 

 two miles from Kelsey Hill. (Furnished by the Engineer of the Hull 

 Waterworks.) 



At Old Pollard Farm. 



Feet. 



Soil 2 



Red brick-clay 4 



Black warp 34 



Eed clay full of stones 20 



Rough gravel with sand and spa- j 9 g 



water J 



Very fine clay, clear of stones 8 



Bed of flint 2 



Black Moor, decayed wood 2 



Blue clay with white sand 1 



Blue clay with white marl t 8 



White marl-clay with small cob- \ g 



bles and flints J 



Chalk with bed of sand 5 



Chalk clear of flint 69 



190 



At Twier's Farm. 



Feet. 



Soil 2 



Cood brick-clay 5 



Black warp 13 



Strong marly clay with stones ... 40 

 Rough gravel-stones and spa- 1 24 



water j 



Fine clay 1 



Dark-green sand 11 



Blue clay with white sand 2 



Hard mixture of blue clay and \ ^ 



white marl J 



Red clay with white marl 10 



Chalk 7 



White sand which blew up into 1 j 



the pipes 20 feet high J 



Chalk clear of flints 50^ 



1781 



Here beds of gravel occur low down in the Boulder- clay. The 

 upper three beds belong probably to the alluvial deposit of the 

 marshes. The stony clay beneath representing the Boulder-clay, 

 would, if continued on the same level, range under the Kelsey Hill 

 sands and gravels, which therefore, so far as superposition is con- 

 cerned, might form an upper member of this series. But the gravel 

 is more worn and more shingly than is usual in the mass of Boulder- 

 clay. It has more the character of beach-shingle ; for not only have 

 we littoral shells, but rounded blocks of chalk, pierced by Annelids 

 and the Pholas crispata, are also common. These are features which 

 I did not notice in the coast-section ; nor have I there observed, 

 in those thick beds of sand, the fine lamination and large oblique 

 bedding. These may be owing to the nearer proximity to the mouth 

 of the old river. Further, I found in the coarse gravel of Kelsey 

 Hill pebbles of limestone showing glacial scratches more or less 

 obliterated. These facts therefore afford grounds to view the Kelsey 

 Hill gravels as partly reconstructed beds, deriving some of their ma- 

 terials from the lower beds of the Boulder-clay and associated gravels. 

 The worn and irregular state of the surface of the Boulder- clay at 

 Paul Cliff also gives some support to this partial denudation of the 

 lower beds of the Boulder-clay before the end of that glacial period. 

 On the coast the gravel-beds associated with the Boulder- clay are 

 spread out with more regularity and conforniability. 



The greater number of shells now obtained from these beds show, 

 however, a more northern character than was at first apparent, and 

 tend therefore, taken in conjunction with the occasional capping of 

 their seams of clay like a Boulder-clay, and the fact of a general 



* The terms used by the workmen in these and the other well-sections are re- 

 tained. The small diameter of the bore-hole, and the presence of water, often 

 render it difficult to judge accurately of the materials. 



