170 



HARD WICKE'S SCIENCE- G OSSIP. 



about Sheffield and Barnsley. Coals with other 

 names, and on different horizons, are worked about 

 Wakefield and Leeds, Halifax and Bradford. 



Then, above these measures rich in coal, we have, 

 towards the upper or eastern boundary of the coalfield, 

 a series of measures with few coals and few thick 

 or massive sandstones. The escarpments made by the 

 sandstones in this part of the coal measures are, 

 consequently, usually feeble and indefinite, giving 

 rise to a slightly undulating country in which no beds 

 are traceable for more than a short distance. Two 

 rocks, however, are not without a perceptible in- 

 fluence on the landscape east of Sheffield, and are 

 also largely quarried. These are the Wickersley 

 Rock, much used for grindstones, and the red rock of 

 Rotherham. The last is a sandstone of Carboniferous, 

 and not, as used to be supposed, of Permian age, 

 which rests unconformably on the beds below, and is 

 altogether perhaps the most singular geological phe- 

 nomenon in the district. A more detailed account 

 will shortly be given of it. 



The lowest beds of the district, the millstone grit, 

 may easily be reached from Sheffield, as the lower 

 coal measure belt of country is much narrower than 

 usual due west of that town. Leaving Sheffield in a 

 westerly direction by the Glossop road, the outcrop 

 of the Silkstone coal is passed near the spot at which 

 Cell Street crosses, and we are on lower coal measures. 

 A gradual ascent in the same direction brings us to 

 Stephen Hill, near which the fault, ranging north- 

 east and south-west, crosses the road, which here 

 divides the lower coal measures from the millstone 

 grit. The road hitherto has been a gradual ascent, 

 and is here about 774 feet above the level of the sea, 

 the height of the alluvial flat of the Don at the 

 Wicker being 150 feet. Hence a gentle descent of 

 half a mile brings us to the edge of the Rivelin 

 valley, and the brow of the fine escarpment of the 

 Third Grit, which here is conspicuous on both sides 

 of the valley, and which, though west of Bell Hagg, 

 and a corresponding point on the north side, has its 

 base 200 or 300 feet above the stream, soon descends 

 to its level eastward at Little London Wheel. The 

 nature of this coarse, massive grit and conglomerate 

 is shown in Bell Hagg quarry. The view from this 

 point is very wild and romantic. Few spots, if any, 

 excel the Rivelin valley as an example of the influence 

 of subaerial denudation in the erosion of river valleys, 

 as we now see them, and the production of escarp- 

 ments. I may here also remark, by the way, that 

 few influences are likely to be more efficient in 

 removing any notion that may linger in the mind as 

 to the influence of faults in the production of river 

 valleys than an inspection of the Geological Survey 

 maps of coal measure districts, especially those of 

 six inches to a mile. Of course, I do not mean that 

 it will be found that faults never coincide with river 

 valleys, but that they show no preference for them, 

 and that the number of faults ranging along them is 



not, on the average, greater than in other parts of 

 the map. 



The millstone grit is, about Sheffield, generally 

 divided from the lower coal measures by faults. 

 These lower coal measures are somewhat intermediate 

 in character between the millstone grit and the 

 middle coal measures. South of the Don and west 

 of the Sheaf, the middle coal measures occupy less 

 than a square mile of ground, this being the area 

 between the Don, Sheaf, and Porter Brook, on which 

 the chief business streets and buildings are situated. 

 The lower coal measures occupy all the ground 

 around the above area. On the south, west of Norfolk 

 Park, about Heeley and Bannercross ; west, about 

 Crookes and Crookes Moor, and, crossing the Don, 

 a large area west of Pitsmoor is all lower coal 

 measure ground. A short distance south-west of 

 Sheffield, and north-east of Ecclesall Bierlow, may 

 be seen the fine escarpment of Brincliffe Edge, the 

 most striking of those of the lower coal measures in 

 the immediate vicinity of Sheffield. Parallel to it, 

 but nearer Sheffield, and consequently above it, is a 

 sandstone, the escarpment of which, though clearly 

 defined, is comparatively feeble. These two rocks 

 are worth noting here, as they are the representatives 

 of the two most important and persiitent sandstones 

 of the lower coal measures. The Brincliffe Edge 

 sandstone is known, north-west of Sheffield, as the 

 Greenmoor Rock, and further north, again, as the 

 Elland Flagstone. It is compact and fine-grained. 

 The uppermost of the two sandstones (which forms 

 Machon Bank) is known north-west of Sheffield as 

 the Grenoside Rock. It is a rough gritty stone, and 

 though not so persistent as the Greenmoor Rock, 

 makes a much bolder escarpment, and covers much 

 more ground, about Grenoside and Wortley. East 

 of the Sheaf at Heeley it rapidly dies away. The 

 variations in the relative preponderance of these two 

 rocks in the landscape, and in the heights of the bases 

 of their escarpments are very remarkable. 



North-west of Sheffield few excursions will repay 

 the lover of geology and scenery better than one to 

 Wharncliffe Crags. These crags are the escarpment 

 of a rock of lower coal measure age lying below the 

 Greenmoor and Grenoside rocks, which are a few 

 hundred yards east of it, and maybe seen at the same 

 time. Unlike them, however, the Wharncliffe rock 

 sinks into insignificance a very short distance north 

 and south of the crags, though at the crags it is a 

 hard, massive, thick-bedded sandstone. The view 

 westward from near Wharncliffe Lodge is very fine, 

 and will not readily be forgotten. The Don runs 

 several hundred feet below, but its course is almost 

 invisible on account of the mass of verdure which fills 

 the river valley as high as the foot of the crags, and 

 contrasts with the high bare moorland beyond. It 

 is also worth while to take a short walk eastward 

 from the crags, and, crossing the Greenmoor Rock, 

 here insignificant in appearance compared with the 



