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 GEOLOGY The other section, that at Brock Hill, is interesting mainly on account of the occurrence of the Ludlow Bone-Bed. Phillips, although he gave a detailed account of the exposure, failed to identify this bed, and it remained for the Rev. F. Dyson to record the discovery.** J. W. Salter then visited the locality, and from the notes which he took and published,*^ it is very easy to see that these top beds of the Silurian are very similar to their equivalents near Ludlow. Above the Upper Ludlow Bone-Bed — ' a series of calcareous nodules, filled with the before-named species [of shells, etc.] and bearing on its surface coprolitic masses and nodules ' — are flaggy Downton Castle Sand- stone beds with Platyschisma helicites ; succeeded by more massive-bedded sandstones ; which in turn are overlaid by the Temeside Shales. Salter extended his researches into the Cradley district, and detected the Ludlow Bone-Bed cropping out in the hill-side behind Hale's End Farm. Woolhope District. — The Woolhope district is i o miles long and 4 J miles broad. Its genesis, as due to the rocks bulging upwards in order to obtain relief from crust-pressure, has already been mentioned, but in this connexion attention may be drawn to the diagrams by the Rev. R. Dixon, which show very clearly that the stronger force was that acting from an easterly direction.*' After the uplift of the district the top of the dome was removed, and the Silurian rocks, with their hard bands interstratified in soft shales, were laid bare.*'' It was from such a surface as this, one of very diverse stratal composition, that denudation — by means of its differential action — carved out the succession of valleys and ridges which rise one above another and encircle, with but few interruptions, the Woolhope ' Valley of Elevation,' as Murchison called it, forming a vast natural amphitheatre, which compels admiration when looked down upon from such a vantage ground as Adam's Rocks, near Dormington. Denudation has removed whatever Carboniferous Beds were originally de- posited over the area previous to the time of crust-crumpling and the Old Red Sandstone, and from out the centre of the dome has scooped all the Silurian Beds down to the May Hill Sandstone, which now forms the rolling, wooded ground, visible from Adam's Rocks in a south-south-easterly direction. Since the publication of Murchison's Silurian System, wherein the re- markable physical features are so clearly outlined and the succession of the rocks so briefly, although so clearly, sketched, many geologists have visited the tract, but few with any ulterior object than to become generally acquainted with so classic a neighbourhood. Phillips described the district on behalf of the Geological Survey, noting very carefully the geographical distribution of the beds, the directions in which they are inclined, and the faults by which they are affected, only one of which, however, is indicated on the Survey map. The Rev. R. Dixon contributed some notes, useful as pointing out the best places for studying the various rock-divisions and for collecting fossils ; while he prefaced his remarks with some observations on the tectonics of the district. G. H. Piper has " Edin. New Phil. Journ. 1856, p, 172. " Tram. Malvern Nat. F. C. pt. 2 (1853-70), pp. 9-12. xiv, pt. 3 (1903), pp. 258-9. " See C. Callaway, Proc. Cotteswold Nat. F. C. xiv, pp. 257-8. IS
 * ^ Tram. Woolhope Nat. F. C. 1867 (1868), p. 174 ; see also T. Melhrd Rends, Proc. Cotteszvold Nat. F. C.