C. T. Clough—The Whin Sill of Teesdale. 437 
sections showing thin beds of sandstone, etc., between Whin, but 
these beds would be found to be continuous with the mass of the 
sedimentary rocks of the country, if we could only trace them on, 
and are not fragments entirely surrounded by Whin (Q.J.G.S. vol. 
xxxi. No. 128, The Section at the High Force, Teesdale). Ac- 
cording to the second supposition the beds have been disturbed by 
the irregularity of the Whin, though the effect of the disturbance 
is seen on the opposite side of it to that on which we see the 
irregularity. Fig. 38 represents the state of the case according to 
this supposition. Unfortunately, it is not usual to get sections 
showing both the top and bottom of the Whin, and I cannot say 
that the case may not be so at times, though I know of no evidence 
for it. But it does not seem at all satisfactory to have to suppose so 
ae 
Wj, 
j Yj, Yy // yy / 7 
Wi {/, y, TOE 
ere 
Y 
Fic. 3.—a a Sedimentary beds. 4 Basalt. 
TTT Ti 
frequently that what we cannot see is different from what we can 
see, that the beds on the side of the Whin we cannot see have 
been disturbed, while those on the side we can see have not been 
disturbed. Moreover, in the case of an actual fracture of the beds, 
I think there would probably remain some indication of the tension 
which preceded it, i.e. the beds would show some tendency to 
assume a dip parallel to the Whin face, even if they had not actually 
done so. 
Fortunately, we have in a few places much more direct evidence 
than mere absence of disturbance, to show that certain beds have been 
absorbed by the Whin. There are a few sections which show at 
once the bottom and top of the Whin, and the beds above and below, 
and so clearly that we may with certainty recognize these beds ; 
and we can see in such cases that certain beds are missing where the 
Whin now is. 
The best section of this kind that I know of is near Lodge Gill, 
in Westmoreland, on the side of the Tees about two miles above 
Caldron Snout. - We have here three sykes, Cockle Syke, Rowantree 
Syke, and Lodge Gill Syke, falling into the Tees from the West ; 
Cockle Syke lies E.S.E. from Rowantree Syke and is about 400 
yards from it (at the points where we wish to compare their 
sections) ; Rowantree Syke lies in the same direction from Lodge 
Gill Syke, and is about 100 yards from it. 
The sections in Cockle Syke and Rowantree Syke are as follows 
beginning from below :-— 
