20 BAKERS NORTH YORKSHIRE. 



In Great Whernside the series is about 600 feet thick, the 

 beds of the summit representing the Upper Plate and Flagstone 

 group of Nidderdale and the Lower Grit ranges down both sides 

 of Coverdale, with the Middle Grit over it in isolated patches 

 to form the highest summits. From the edge of Coverdale 

 proceeding eastwards towards the central valley the mass of 

 moorland slopes with considerable abruptness, and within a 

 short distance of Masham some of the beds higher than the 

 Middle Grit make their appearance, and nearer Tanfield a grit- 

 stone is to be seen which most likely represents the Upper or 

 Brimham Gritstone. In Penhill the series is exhibited as follows, 

 the grit of the summit still apparently representing the Middle 

 Grit of Nidderdale, but with the Lower Nidderdale Grit shewn 

 only in a very imperfect manner. 



feet. 



Grit rocks of the summit 150 



Alternations of plate and flaggy grits with coal } 



in the upper part ) ^ 



Plates, flagstones, etc 60 



Little limestone, chert and plates 80 



Total 540 feet 

 In Buckden Pike, where the surface of the Main Limestone 

 is 1850 feet above the sea-level, the Millstone Grit series is only 

 450 feet in thickness, the summit rock being rather higher in 

 the scale than that of Penhill. But as we proceed westward 

 amongst the remainder of the hills on the south side of Yore- 

 dale we get only a small thickness of the beds of this series, 

 and that is only shewn in the shape of ridges or isolated patches 

 upon a great limestone floor ; as may best be seen in two of 

 the hills in the immediate neighbourhood of Hawes, Dodd Fell 

 and Bear's Head. 



Between Yoredale and Swaledale the series is thickest to- 

 wards the western and eastern extremities of the moorland mass, 

 the Main Limestone being left at or near the surface in the 

 central portion of the range. In the five high summits on the 

 edge of Mallerstang there are from 700 to 800 feet of Millstone 

 Grit beds above the Main Limestone ; on the south side of 



