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 A HISTORY OF STAFFORDSHIRE We know however that before the commencement of the Trias era the Carboniferous strata were intensely folded, fractured and extensively de- nuded, resulting in their more or less complete isolation, so that in North Staffordshire we find the four detached coal basins of the Potteries, Cheadle, ShafFalong and Goldsitch Moss, while the South Staffordshire Coalfield is separated from the northern field by a wide expanse of Triassic rocks. Though the coalfields of the north and south possess many points in common the northern area presents the type development and will therefore be described first. THE NORTH STAFFORDSHIRE COALFIELD Lower and Middle Coal-measures. Situated on the line of the great Pennine uplift or along its western margin it is not surprising to find this coal-bearing region complicated by numerous faults and folds. The folds trend in a general north and south direction, and enclose the four separate coalfields mentioned above. The Cheadle, ShafFalong and Pottery Coalfields may be connected under the Trias of Caverswall, but the small coalfield of Goldsitch Moss is sunk deep in a fold of Millstone Grits, and removed several miles from its sister coalfields. The im- portant coalfield of the Potteries can be further naturally divided into a central synclinal region and a western anticlinal portion. In the latter the coal seams are frequently vertical and occasionally bent on themselves; in the former the coals are sometimes highly inclined but never vertical. The faults, the majority of which trend north and south, are not only many but of very great throw ; one, known as the Apedale Fault, tra- versing the central portion of the Pottery Coalfield in a north and south direction exceeds 600 yards in vertical displacement, while an even larger dislocation extends along the western margin of the coalfield. The faults have exerted a strong influence on the physiography of the district. Thus the Apedale Fault lets in a strip of barren measures in the heart of the coalfield so that the ancient town of Newcastle-under-Lyme lies in a pleasant agricultural district, while immediately east and west there extends the usual grimy landscape of a coal-mining district ; again, on the west a large fault suddenly introduces unproductive measures, when the mining industry abruptly ends. The Coal-measures have been sub-divided into Lower, Middle and Upper; but the exact horizons at which the dividing lines should be drawn have not been definitely settled. Whatever scheme is adopted the lower and middle sub-divisions constitute the storehouse of the chief seams, of which the most important, commencing with the Winpenny Coal, about 1,200 feet above the First Grit, are grouped together. Above this coal there are no less than thirty recognized seams, making a total thickness of over 1 40 feet of coal. A seam towards the middle, known as the Ash Coal, has been taken by some geologists as the base of the middle sub-division, while another seam Bassey Mine Coal has been 12