194 Charles Ketley — The u Red, Rocks'" near Birmingham. 



Lord Dartmouth's experiment, much ridiculed by practical miners, 

 was ultimately successful, and was the beginning of the opening up 

 of a new tract of Coal-measures three-quarters of a mile in width, 

 extending from the "Eastern Boundary Fauljb " to the Heath Pits. 

 This addition to the productive area of the Coal-field has since been 

 extensively worked by numerous sinkings, some of which are noticed 

 below. 



But while the Heath sinking had established the existence of Coal 

 under the Lower New Bed Sandstone, and beyond what was formerly 

 considered the eastern barrier of the Coal-field, it seemed to prove 

 also the existence of another "barrier." There was no "thick" Coal 

 in the shaft of the Heath Pit; thin coals only were found, and it came 

 to be concluded that these occupied the place of the thick Coal, or 

 represented its thinning out. In search of the thick Coal, a " head- 

 ing " from the shaft was driven eastward, and at the extremity of 

 this a boring was made upwards, striking " red rock," and another 

 boring was made downwards, reaching a hard rock, which afterwards 

 was believed to be of Silurian age. After these unsuccessful at- 

 tempts, one of the thin coals in the shaft was followed to the west, 

 in the direction of the old Coal-field, and that led into the thick Coal. 

 Sir Boderick Murchison concluded that the shaft proved to be sunk 

 upon a line of dislocation, the prolongation of the upcast of the Silu- 

 rian rocks of Walsall and Tame Bridge. 



Professor Jukes considered there was a sudden rise of Silurian 

 rocks through the Coal-measures forming a bank, the existence of 

 which had been favourable to the formation of sandstone and the 

 accumulation of clay, but unfavourable to the formation of Coal. 

 From Silurian shale having been found in a coal-pit at Langley 

 Mill, Oldbury, he supposed the bank to be continuous for that 

 distance, about three miles, and he indicated the probable course of 

 it by a dotted line drawn on the map of the Geological Survey. 



Professor Hull looked upon this Silurian bank as part of the 

 original margin of the Coal-field, and supposed it might be traced 

 southwards to the Lickey district. He held that east of this margin 

 there could be no Coal. 



There were different opinions as to what lay east of this Silurian 

 bank, but none were favourable to the existence of workable Coal- 

 measures. The sections of the following sinkings, in the tract above 

 referred to, were supposed to show varying thicknesses of red rocks, 

 held to be Permian, overlying varying thicknesses of recognized 

 Coal-measures supposed to have been denuded. Seasoning from 

 these and other appearances, it was concluded that further eastward 

 a still greater thickness of Permian beds rested upon Coal-measures 

 still more denuded : — 



Permian over Coal-measures 



Coal-measures. over thick Coal. 



Lewisham Pits 315 feet 520 feet 



Lyng Colliery 550 „ 350 „ 



Heath Pits 806 „ 40 „ 



Bullock's Farm Pits 700 „ 330 „ 



Unitt's Poring at the " Ruck of Stones" 664 ,, Abandoned. 



