299 
Mountain Limestone in the centre of the range at Downhead 
must have been rudely torn asunder, producing a central valley in 
the manner shewn on the section. The inclination of the 
denuded portions we can of course only judge by inference, but 
in my opinion they were probably more nearly perpendicular 
than those which remain, if indeed they were not slightly folded 
over, which I think not improbable. 
As to the Millstone Grit, I have little doubt that it was partially 
folded over. We sce evidence of this in the undenuded portions, 
and the fold was probably even more decided in.the portion which 
has been removed. 
In the Coal Measures the action appears to have been of two 
kinds. At the moment of elevation they were probably nearly 
perpendicular as we now find the Limestone, but subsequently, 
the Pennant Rock and the New Rock or Sandstone series have 
been folded completely over, dipping southwards at an angle of 
from forty-three to forty-five degrees. This can be shewn both on 
the surface and in the mines and it does not admit of doubt. 
The Vobster series, however, shows an entirely different effect. 
The strata consist of very tender shales, and they appear to have 
acted like a wedge, settling down between the hard Coal Measure 
sandstones of the New Rock series on the one hand and the still 
harder Millstone Grit on the other ; assisting, it may be, to force 
over the New Rock group, but crushing themselves to pieces in 
the process. * | 
Of the physical disturbances which thus took place, the Lucking- 
ton and Vobster Limestones are probably the result; and if I 
have satisfied you that they have not been upheaved from. beneath, 
they must in some way have been folded over from that range, 
although we may not be able to realise how all this has been 
‘ 
'* T have little doubt the higher portions of the Millstone Grit and Mountain 
Limestone rolled over on the Vobster Shales as they thus settled down, but I 
' have not attempted to show it in the section. 
