Page:VCH Herefordshire 1.djvu/79

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GEOLOGY it is seen to be made up of an anticlinal of clay, flanked with debris of Welsh grits, Ludlow rocks, clay-slates, fragments of igneous rocks, &c., measuring anything up to 5 ft. 6 in. by 2 ft. by i ft. 9 in." Hereford itself is built for the most part upon river-gravels, into which the Glacial deposits seem to merge. Excavations in the city and its vicinity frequently expose the gravels, and occasionally remains of mammoth are found. The gravels which were formerly worked at Wilcroft and Hagley were composed of a remarkable assemblage of rocks — large angular pieces of Old Red Sandstone, blocks of Cardington grits from Church Stretton, fragments of Clee Hill basalt, Hope Bowdler trap, and quartz-pebbles ; '^ while Curley obtained a pebble containing the cast of a Dactylioceras commune.^ The hill-sides between Richard's Castle and Kington and Kington and Hay, are often obscured with thick accumulations of debris, which render the ground difficult of cultivation ; but between Richard's Castle and Kington, away from the hills, the Superficial Deposits become finer in texture, and partake, to a considerable extent, of the nature of the rocks upon which they rest. Thus at Luston, in the lowlands, near Leominster, Murchison observed a section of drifts based upon the Old Red Sandstone, in which red and white sand predominated, and was veined with one or two seams of gravel. But sometimes patches of coarser material occur, as at Wickton, near Leominster, where large masses of Silurian Limestone thrown out of excavations for drains at first suggested an inlier of Silurian rocks as at Shucknall Hill. Special excavations, however, showed that such was not the case : the blocks had been transported, probably by ice-action.'* In the Woolhope district '" coarse debris of the local rocks is heaped up against the hills along the south-western side of the inlier, and are spread out in front of the gorge of the Pentalow Brook at Mordiford. In the road-side a short distance to the east of the Moon Inn at Mordiford, is a very clear section of the deposits, which was studied by Murchison, and later by the Rev. F. Merewether.'* Merewether also described sections by the road-side between Mordiford and the bridge over the Wye to Holme Lacy, and in the village of Fownhope, in all of which a similar deposit was seen. Murchison remarked that the ' Woolhope Valley of Elevation ' was one of ' clean ' denudation ; there was no accumulation of local debris, and he had not noticed any foreign drift. Merewether, however, found a patch of local debris at least several acres in extent near the Court Farm, Woolhope ; and quartz-pebbles, which Symonds pronounced foreign to the district, in the Haugh Wood. In the Malvern district Superficial Deposits occur in the neighbourhood of Eastnor and around Colwall. The section at Clincher's Mill is well known. The component materials of the deposit are mostly of local origin. At the base the section, in Symond's time, showed large angular masses of diorite, Llandovery, Wenlock, and Ludlow rocks ; in the middle similar materials, " See Proc. Coitestvold Nat. F. C. xv, pt. 3 (1906), p. 196. " Records of the Rocks, p. 166. " Trans. Malvern Nat. F. C. pt. 3, (1853-70), p. 27. '* Trans. Woolhope Nat. F. C. 1868 (1869), pp. 3-6. " Silurian System (1839), pp. 436-7. " Trans. Woolhope Nat. F. C. 1870 (1871), pp. 173-7 5 'bid. 1877, pp. 18-21. 31