144 THE GEOLOGY OF MOW COP, ETC. 



diminish in thickness, and die out proceeding southwards. 

 The Macclesfield grits with their shales are 1,000 feet in 

 thickness, north of Biddulph 600 feet, and west of it 400 

 feet in thickness. Across the red rock fault, east of 

 Macclesfield, besides the grit coal we have likewise the 

 tail end of the Lancashire coal measures ; these consist of 

 four or five poor thin seams, of which the third is the, 

 best for household purposes. In the Biddulph Valley both 

 the middle and lower coal measures are worked. As I 

 have before stated, the Yoredale series of rocks, which lie 

 immediately below the grits, have been brought up by the 

 Astbury lime kiln fault with a throw or thickness of 2,000 

 feet. On the western side of Shutlingslow, owing to an 

 upcast fault, they will have a throw of about 1,500 feet. 

 We have probably 1,200 feet of them near Macclesfield. 

 The upheaval of those Yoredale rocks, forming the anti- 

 clinals of Bosley Minn and Gun Hill, is 1,200 feet above 

 the sea. To the east of Biddulph Moor there is an anti- 

 clinal of the Yoredale rocks, which from the shattered state 

 of the strata appears to have been formed under great 

 disturbance. Like the grits, these rocks become thinner 

 proceeding southwards, and it is said that they extend no 

 further than the Leicestershire coalfield. As I have pointed 

 out before, the fault at the Astbury lime works has a 

 probable maximum throw of 8,000 feet. The nearest 

 approach to the surface we have of the Buxton limestone, 

 near Macclesfield, is to be seen in the forest at Saltersford. 

 Here, in a line with the anticlinal axis of this part of 

 Cheshire, the carboniferous limestone will probably lie at 

 a depth of about 1,500 feet below the surface. The red 

 rock fault, as I have named before, skirts the town of 

 Macclesfield at a distance of one quarter of a mile to the 

 east. Several fine sections of this fault are to be seen 

 between Mow Cop, Congleton, and Macclesfield, of a very 



