﻿74 DE. W00LAC0TT ON THE SUPERFICIAL DEPOSITS, ETC. [Feb. I905, 



The variation in the character of these deposits has been already 

 discussed, and the following typical borings show the changing 

 nature of them clearly : — 



Newton Hall, Framwellgate. 



Feet 



Soil 1 



Sandy clay 1 



Sand, with ' scares ' of coal 4 



Sand, with water 5 



Leafy clay 1 



Sand, with water 1 



Leafy clay, 'scares' of coal 



Gravel 



Leafy clay 



Loamy sand 



Stony clay 



Sand, with water 57 



Fine loamy clay 9 



Sandy clay 



Sand, with water 10 



Soft leafy clay 10 



Stony clay 6 



Loamy clay i) 



Loamy sand 10 



Loamy sand and leafy clay 67 



Stony clay 9 



Stony clay 3 



inches 

 6 

 

 

 

 6 

 6 

 6 

 4 

 2 





 5 

 



7 



2 

 7 

 

 

 



1 



Sea-level. 



Percy Main. 



Feet inches. 



Blue stony clay 78 6 



Sand 2 1 



Blue stony clay 19 ^ Sea- 

 Blue stony clay 48 8 level 



Dry stony clay 5 6 



Leafy clay 2 6 



Sand 1 8 



Sand and clay 2 3 



Stony clay 2 4 



Gravel 1 



Sand and water 1 11 



Leafy clay 9 6 



Sand 4 1 



Gravel 3 10 



Total thickness 



183 3 



Total thickness 232 



IV. The pre-Glacial Surface of the Country. 



A detailed study of the borings and of the exposed rock-surface 

 enables us to form a fairly-accurate idea of the contour of the pre- 

 Glacial surface of the country, and shows that the superficial deposits 

 lie in a series of valleys which are (as will be more clearly proved 

 afterwards) the courses of pre-Glacial streams. Therefore, if we 

 had a sufficient number of sinkings, it would be possible to reconstruct 

 the pre-Glacial drainage of the country. An attempt is made in this 

 paper, so far as the material at command admits, to do this. All 

 the available borings have been put in on 6-inch maps, with their 

 height above sea-level and the depth of the superficial deposits ; 

 and then these have been transferred to 1-inch maps, which had 

 the exposures of rock previously marked on them, and the height 

 of the rock-surface above, or depth below, sea-level indicated. In 

 this way the courses of the pre-Glacial valleys have been traced, 

 and the present contour of the rock-surface roughly mapped out. 

 It has also been found possible to compare the pre- and post- 

 Glacial drainage, and to show that the two differ considerably one 

 from the other. 



The rock-surface in many of the valleys lies at a considerable 

 depth beneath sea-level. The following are some of the deepest 

 borings that prove this : — 



