343 
very clearly the existence of a " per- 
sistent " anticline of pre -Permian date 
extending across the Vale of York, 
from which we gather that the Coal 
Measures have been denuded off this 
anticline with the result that the 
Permian rests directly on the Millstone 
Grit. Professor Hull shows the northern 
boundary as a large fault, or series of 
faults, running west to east, but the 
writer cannot see that this is justified, 
inasmuch as the faults existing at the 
northern extremity of the exposed coal- 
field have not, to his knowledge, been 
proved under the newer rocks to the 
east. The matter is, however, very 
thoroughly dealt with in Professor 
Kendall's report. It would seem 
probable that the hole was put down 
not very far south of Professor 
Kendall's Wharfe-Market Weighton 
axis, and that the striking variation of 
the dip is accounted for by the folding 
of the strata, perhaps not the actual 
Wharfe anticline, but some secondary 
and more acute fold of possibly only 
a local nature. 
It has been suggested, doubtless 
with a great deal of truth, that the 
seams of the Middle Coal Measures 
might exist in normal conditions and 
of normal thickness in the neighbour- 
hood, but that on the limb of the fold 
through which it is supposed the bore- 
hole passed they have diminished in 
thickness or thinned out altogether. 
Mr. Emsley Coke has suggested that 
the beds of fke-clay passed through 
