200 Kendall : The Concealed Coalfields of Yorkshire , elc. 



which is observed between Shirebrook and Cresswell on the 

 borders of Derbyshire and Xotting'ham. 



It will be convenient that I should give a short summary of 

 the evidence for each of the boundaries. 



TJie Western Boundary. — This is the very obvious anticlinal 

 fold of the Pennine Chain. Of its early history we have no 

 record, but the close similarity between the Coal Measures of the 

 opposite sides of the chain, the resemblance extending" even to 

 small details between some of the seams in the eastern and 



western fields, and the continuity of the Lower Carboniferous 

 rocks are perfectly decisive proofs, often ignored, of the former 

 continuity of the Coal Measures over the Pennine area. The 

 first arching movement of which we have any geological record 

 took place after the Coal Measures were laid down, the ridge 

 rose, and though much wasted and worn down by the weather, 

 it remained as a low barrier separating' the Permian sea or lake 

 that washed its eastern slopes from another watery area on the 

 west. Of its subsequent movements we know but little ; it is. 



Naturalist. 



