177 
INGLEBOROUGH. 
PART V. DEVONIAN AND CARBONIFEROUS. 
BY T. MCKENNY HUGHES, M.A,, F.R.S., WOODWARDIAN 
PROFESSOR OF GEOLOGY IN THE UNIVERSITY OF CAMBRIDGE. 
I have given great prominence to the discussion of the 
character and relations of the Bala and Silurian rocks because of 
the great interest attached to this easternmost outcrop exposed 
in the deep valleys which have been carved out on the east and 
west of Ingleborough, but this is essentially a country of Car- 
boniferous rocks. 
As we stand on the great limestone terrace of Ingleborough 
(see Pi. XXIV.), and look out east across the valley of the 
Ribble, we see the bold outline of Penyghent, owing its 
profile to the alternations of sandstone, limestone, and shale 
which have differently resisted the various denuding agents 
that have for ages been at work upon it. 
The top of it consists of beds higher in the series than any 
we have on Ingleborough, and the first shoulder from the top 
corresponds to Ingleborough's cap of Millstone Grit. The 
next shoulder is due to the massive sandstones which make 
up the upper part of the Yoredale rocks (the Hawes Flagstone 
Series), while the top of the Mountain Limestone on which we 
stand is seen at the foot of the steeper slopes opposite, and 
its scars are visible here and there projecting out towards Ribbles- 
dale. Though we know that Bala and Silurian occur a.11 along 
the bottom of the valley from Horton below us, and as far south 
as Stainforth, we see no features due to them. The conspicuous 
rounded hills are the moraine mounds of the receding glacier-ice 
which seems to have been long arrested here. Lower down we 
find the Bala and Silurian almost continuously beneath the great 
unconformity, and here and there in roches moutonnc'es in the 
valleys below, but, except in Crummack-dale, we rarely see 
features obviously due to them. But we have here great 
opportunities for studying one phase, at any rate, in the incoming 
