]40 



subsequently been filled by the infiltration of other matter, 

 and in horizontal faults we could hardly expect to find similar 

 effects; but although in them the lines of fracture are 

 differently composed they are not the less distinct. 



In the under surface of the upper strata or the part thrust 

 forward the fractured ends of the beds are frequently bent 

 downwards, but the inequalities appear to have been rubbed 

 off, leaving a smooth and polished surface. The upper surface 

 of the strata beneath has also been worn smooth in places, 

 but on the whole it is more irregular, the ends of the veins 

 and beds having invariably been either turned up where 

 broken off, or forced into a succession of smaller overlaps by 

 the immense mass moving above. Between these clearly 

 defined lines there exists a thick layer of crushed materials 

 of every kind. Shale, generally much disintegrated, with 

 occasional fragmentary pieces of coal and sandstone, fill up 

 the intervening space, the whole being so loose and friable 

 that when a shaft has been sunk through the fault, ordinary 

 masonry is scarcely sufficient to hold the broken materials 

 back. In the two smaller dislocations, which I have associated 

 with the great overlap and shown on the section, the same 

 general features prevail, the only difiierence being that they 

 appear to affect only the two lower veins. In order to 

 show more clearly the effect of these disturbances, I have 

 had a section of part of the Bull Vein constructed on a 

 larger scale, and on examining it you will find many 

 evidences of the violent action to which the strata have 

 been subjected. 



I would now in conclusion pass on to describe the 



FOLDED AND CONTORTED STRATA OF THE 

 VOBSTER AND NETTLEBIDGE VALLEY, 



and I hope afterwards to make it clear that the various 

 disturbances referred to are not so unconnected as may at 



