A HISTORY OF STAFFORDSHIRE whence they were termed ' Yoredale Rocks,' the change from this supposed northern type being considered to take place in the neighbourhood of the great Craven faults. According to Messrs. Hind and Howe the Yore- dales of Yorkshire are the equivalents of the undivided massive limestone of Derbyshire, which splits up in the north into several bands separated by inter-bedded shales. The Pendleside Series they regard as occupying a superior position, and containing a fauna distinct from the Carboniferous Limestone of Derbyshire and the Yorkshire Yoredales. 1 MILLSTONE GRIT SERIES This sub-division lithologically resembles the Pendleside Series, differing chiefly, as the name implies, in the greater prevalence of gritty material, aggregated into bands of considerable thickness separated by black and grey shales. While a definite band of grit (First Grit or Rough Rock) happens to separate the sub-division from the Coal- measures above, no such well marked or persistent bed indicates its junction with the Pendleside Series, to which it is allied in the closest possible stratigraphical manner. Conspicuous objects in the landscape, the different bands of grit follow each other in consecutive order with their separating bands of shale, and have been named from above downward : First Grit (Rough Rock or Farewell Rock of the miner), Second Grit (Haslingden Flags of Lancashire), 'Third Grit (Roaches Grit), Fourth and Fifth Grits (Kinder- scout Grits). These constitute in the north and north-east portion of the county grit bands of singular persistency, but traced southward they are found to decrease gradually till around the Pottery and Cheadle Coalfields only the First and Third Grits remain. Some distance below the Kinderscout Grits and separated from them by shales there lies an impersistent bed of grit, sometimes known as the ' Yoredale Grit,' which has been regarded in Derbyshire as the base of the series, though avowedly an artificial datum line. 2 Throughout nearly the whole length of their outcrop the Millstone Grits can be recognized almost at a glance by the distinctive features to which they give rise. The splendid escarpment of the Roaches and ' The Rocks,' the crags of Ipstones and the numerous ' Edges ' Axe Edge, Ladderedge, Brown Edge, Congleton Edge and other less marked but still conspicuous ridges have been carved by denudation out of the various bands of grit whose broad sheets of heather-clad rocks end in rugged crags standing boldly out in the air, while the flanks and valleys lying at their feet have been fashioned out of the interbedded shales. These bold, bare, rocky ridges impressed early writers and seem to 1 For a full account of the Pendleside Series the reader is referred to the paper by W. Hind and J. A. Howe, ' The Geological Succession and Paleontology of the Beds between the Millstone Grit and the Limestone Massif of Pendle Hill, and the equivalents in certain other parts of Britain,' Quart. Journ. Geol. Soc. Ivii. 347 (1901). 2 ' The Carboniferous Limestone, Yoredale Rocks and Millstone Grits of North Derbyshire ' (Mem. Geol. Survey), p. 8 (1887). IO
