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DISLOCATIONS OF THE BROWN CLEE COAL-FIELD. 



The coal measures of these hills are intersected by a vast number of small faults, one set of which 

 trend from north to south, the other from east to west. In the Abdon Barf there are four principal 

 faults (see Map), two of which have the north and south direction, the other two from east to west 

 cutting the former at right angles. The north and south faults range along the coal measures on 

 the eastern slope of the hills, where no basalt overlies them, one near the junction of the coal with 

 the Old Red Sandstone, the other passing within two or three hundred paces of the cap of basalt. 

 The two transverse faults (termed facing faults) are about eleven yards in width, and affect all the 

 measures and faults up to the edge of the basalt, and are therefore of the most recent date. The 

 north and south faults are upcasts towards the basaltic summit ; the principal or lower south and 

 north fault being an upcast of twenty-six yards. The upper north and south fault is only an upcast 

 of about six yards, and neither of the east and west faults exceeds that amount of dislocation. Be- 

 sides these, there are innumerable minor north and south faults, which are all upcasts reckoning 

 from the Old Red Sandstone of the surrounding low country as a base line. (See coloured section, 

 PL 31. fig. 4. south-east end.) 



In the Clee Barf the faults are not large, and unlike the Abdon Barf the coal has been 

 proved, if not worked out, under every part of it. In this hill most of the faults are 

 more or less from east to west, producing small and trifling upcasts to the south. The 

 fissures resulting from these dislocations are filled with an indurated breccia of coal 

 measures (clods, shale, sandstone, &c), the miners persisting that no fragment of jew- 

 stone or basalt was ever found in them. 



The most extensive of the east and west faults are those by which a large mass of the 

 Old Red Sandstone has been heaved up to the same level as a portion of the coal, so as 

 to occupy the depression between the two basaltic summits, and thus to separate the coal 

 measures into the two small tracts described. (See Map and section, PI. 30. fig. 6.) 



The bare recital of these various dislocations may have caused my readers to infer, 

 that the same beds of coal must be found at many different levels, and they will doubt- 

 less also perceive that such disturbances, added to the ascertained fact of the thinness of 

 the coal seams, must ever render the Brown Clee coal-field of slight economical value. 



face terminates at the pit mouth in a wooden, trough-shaped funnel. The result of this simple machinery is, 

 that a strong column of air being forced down this cylinder, the wind coDected in the chambers is expelled by 

 the shaft mouth, on in other words an equilibrium is established. It is believed by the workmen that the wind 

 enters the galleries through the cracks on the sides of the hills. The men at work at the pit's mouth shelter 

 themselves from the tempest by hurdles secured to large blocks of basalt. 



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