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 A HISTORY OF HEREFORDSHIRE Sandstones have been extensively worked on Gorsley Common ; but then they dip dow^n and, as far as we know at present, disappear beneath the Old Red Sandstone. May Hill District. — Only a portion of this district is in Herefordshire, that around Aston Ingham. All the Silurian rocks, from the May Hill Sandstone to the Temeside Beds, are present, but as they resemble their equivalents in the Malvern and Woolhope districts it is unnecessary to go into details. It may be mentioned, however, that since the days of Murchi- son and Phillips this district has received little or no attention. Hagley Inlier. — The occurrence of the highest Silurian Beds at this locality was first noted by J. Scobie, the first honorary secretary of the Woolhope Naturalists' Field Club. H. E. Strickland described the beds in detail," and Symonds has also contributed remarks. The large quarry in which the succession was first made out is overgrown, but at the base were the Upper Ludlow Shales from which Scobie obtained the Pterygotus probletnaticus described by Salter ; then came the Upper Ludlow Bone-Bed, full of fish-remains, succeeded by the Downton Castle Sandstone, according to Symonds, 6 ft. 6 in. thick ; and lastly the Ledbury Shales, of which there was seen a thickness of 4 ft. Shucknall Hill. — Murchison ^' and Phillips ^' have both described this inlier. The Aymestrey Limestone is the rock most in evidence and has been extensively quarried ; but the Upper Ludlow Shales are also exposed and, according to Murchison, were worked at one time for ' Walker's Soap.' Devonian System The Old Red Sandstone is the rock-formation which extends over by far the greater part of the county. It gives rise to ground of a rich red colour, and the change in tint from these tracts to those where the pale-coloured Silurian rocks prevail is most noticeable. Correlated with this change in the rocks of a district is a certain amount of variation in the flora. Murchison *° was the first properly to investigate the Old Red Sand- stone of Herefordshire and remarked that there was no better exhibition in England and Wales of this great series of red rocks, ' so clearly inter- calated between the Silurian and the Carboniferous,' than in the Black Mountains and the Fans of Brecknockshire and Carmarthenshire. The precise thickness of the Old Red Sandstone in Herefordshire is not known. Murchison estimated it at between 9,000 and 10,000 ft. That was when the Tilestone was included. Phillips placed its maximum at 8,000 ft. and other authors at thicknesses varying between 3,200 and 6,500 ft. Since in Shropshire to the north the Old Red measures about 3,700 ft., and at Abergavenny to the south, 4,200 ft., in the intervening tract the mean of these two numbers, namely, 3,950 ft., might reasonably be expected for its average thickness. " Quart. Joum. Geol. Soc. viii (1852), p. 381 ; see also ibid, ix (1853), p. 8 ; Trans. Ifoolhofe Nat. F.C. 1870 (1871), pp. 167-72. ^^ Si/urian System (iS3g), p. ^3S- ™ o-, • o ,„ » 5' Mm. Geo/. Surf, ii, pt. i (1848), pp. 179-80. " St/urian System (1839), PP- 169-94. 18