90 RASTALL : THE INGLETONIAN SERIES OF W. YORKSHIRE. 
out, observations of dip on the surface are of little value and 
no folds are ever clearly seen. In the absence of any clear 
evidence to the contrary, the succession may be assumed to be 
continuous. Since the Coniston Limestone follows on in ap- 
parent, though probably deceptive, conformity at the S.W. 
end, and in the Ribble valley is succeeded in its turn hy Silurian 
beds, the probability is that the sequence of the Ingletonian 
rocks is an ascending one from north-east to south-west. 
Beginning, therefore, at the lowest visible bed of the series 
in the neighbourhood of God's Bridge, we find that the first 
half mile of the valley is occupied by an alternation of slates 
and thin bands of flags and grit, which are exposed here and 
there in the bed of the river, and in the fields on either side 
of it, especially above the Ingleton and Hawes high road. This 
part of the series is much obscured by drift, and very little can 
be said about it. Just to the soutli of Twisleton Dale House 
there comes in the thick mass of coarse conglomerate, which 
is now largely worked for road metal, &c., by the Ingleton Granite 
Company. This rock, which has a total thickness of some 800 
feet, is of great interest, and will be described in detail in a 
subsequent section. Below this, for about two-thirds of a mile, 
is a rapid alternation of slates and grits, very similar to the 
beds seen in the upper part of the valley. Drift is also abundant 
here and the details are difficult to make out. From the ford 
at Beezley's downwards the rocks are magnificently displayed 
in the great series of gorges before described. Here are several 
thick bands of slate which were formerly worked to a considerable 
extent and are well-exposed in large quarries. The southernmost 
band is continued into Kingsdale and has been quarried on the 
western side of the stream close to Pecca Bridge. Anotlier 
band appears at the foot of Thornton Force, and has been hol- 
lowed out into a large pool. 
The Horton Area. 
The rocks of the Ingletonian series occupy an area of about 
half a square mile in the valley of the Ribble, in the neighbour- 
hood of Horton-in-Ribblesdale. They are exposed in scattered 
patches, of which the most important are in the railway cutting 
