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was found to constitnte at least a part of the accumulation, 
it is probable that Till is present among the other drift 
patches. If this be so, it indicates that an ice sheet at one 
time overspread the area. But it seems likely that the 
amount of Till produced can never have been very great ; 
for it is hardly probable that, if any large quantity had been 
formed, denudation would liave made such a clean sweep of it 
as to leave only the few patches that now exist. At least, if 
any one maintains this, he must be prepared to explain why 
it was that denudation worked with such special thorough- 
ness in this particular area. Why, if this part of the 
country was covered by an ice sheet so little Till was formed, 
it is not easy to say ; but it may have been because the ice 
had its southern termination hereabouts, and being thin, was 
not able to exert any large amount of grinding action. 
But the explanation of the distribution of the drift over 
the area in question is only part of a larger problem, to the 
solution of which but little progress has yet been made. 
One instructive fact in connection with this patch of 
drift remains to be mentioned. Before the railway was 
made, a bore-hole was put down near the turnpike road. The 
borers had nothing but local experience to rely on, and 
having never seen Boulder Clay, were much puzzled by the 
strange stuff that came out of the hole. Finally, they came to 
the conclusion that they could account for what they had found 
in no other way, but by supposing they were on a fault, and it 
became an established article of faith that a large fault, which 
there was every reason to believe existed somewhere in the 
neighbourhood, but whose exact position was unknown, ran 
through the bore-hole. So little doubt was felt on the point, 
that an exchange of coal between the proprietors of two neigh- 
bouring collieries, on opposite sides of the supposed fault, was 
negotiated and all but concluded, when the railway cutting 
was made and the fault proved to be imaginary. It is hardly 
