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 A HISTORY OF HEREFORDSHIRE At one time it was generally believed that in the Glacial Epoch Here- fordshire was submerged, and that floating ice dropped the large boulders which are now stranded on many of the hill-tops ; while beneath the waters were accumulated gravels and High Level Drifts. Symonds and his con- temporaries thought that after this first submergence there was elevation, and that over what was formerly the sea-floor roamed the mammoth and Siberian rhinoceros, the musk ox, and the reindeer ; while man dwelt in the caverns in the hill-sides.*' Murchison also believed in the submergence of by far the greater part of the county, but thought that the materials of the Superficial Deposits had not travelled far, and had been mainly derived from the hills on and just beyond the north-west limits of the county. The most important observa- tions he made in the light of modern ideas were, that the coarser kinds of Superficial Deposits extended farthest east and south-eastwards in front of the gaps in the western hills, and that the materials were arranged with little evidence of stratification over hill and combe alike. Murchison no doubt saw the accumulations now considered to be of morainic origin, but failed to grasp the full significance of the facts.*' After Murchison's researches, until quite recently, the Superficial Deposits attracted little attention, although it is true that a number of vertebrate remains had been collected from time to time from isolated sections. Now they are the subject of much active investigation, and much valuable informa- tion may be expected in the near future on the latest but by no means the least interesting period of the geological history of Herefordshire. Mr. T. S. Aldis appears to have given the incentive to the work. He thinks that in the Glacial Epoch Herefordshire was probably occupied by a ' mass of comparatively stagnant ice of great depth,' but before this idea can be accepted more information is necessary.'" The deposits which are undoubtedly morainic in origin occur principally in the western part of the county. In the neighbourhood of Willersley, in the Wye Valley, near Hay, the ridge running out from Merbach Hill is regarded by Mr. Aldis as a lateral moraine, which caused the diversion of the Wye from its old channel for a considerable period, and he thinks that it was only in comparatively recent geological times that it was enabled to regain its former course. The pecuhar ridge extending southwards through Norton Canon and Staunton on the Wye, and south-westwards to Brobury, Mr. Aldis considers to be a terminal moraine ; and he also thinks that during closing Glacial times the district around Herefordshire was a lake broken with a few islets — some, the remnants of ancient hills ; others, moraine-heaps. The Rev. H. E. Grindley has recently shown that a great terminal moraine, some ten miles long and between two and three broad, stretches from near Kingstone Grange, six miles south-west of Hereford, to Wellington Bridge some five-and-a-half miles to the north of the city. Its course is mdicated by a number of gravel-pits, and the ridge itself is cut through by the Wye at Breinton, where a section shows that the component materials are imbedded in more clay than usual. The best section of the moraine, however, is that at Stretton Sugwas, in a large gravel-pit by the side of the railway, where ^ See Old Stones and The Severn Straits. '' Silurian System (1839), PP- S i i-i5- »» Trans. Woolhope Nat. F. C. 1902-4, pp. 3 2 5-9- 30