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 A HISTORY OF RUTLAND Smaller displacements occur near Pilton, Edith Weston and Whitwell and again near Clipsham to the northward. The Pleistocene deposits, unlike the Jurassic rocks, have no regular dip or inclination, but rest irregularly and unconformably on the older rocks, and occur at all levels from the hill-tops to the valley-floors. Un- der the head of Pleistocene it is convenient to include the newest river- gravels and the recent alluvium, though some prefer to exclude these from the Pleistocene series and to group them as Neolithic or Recent. The following is a tabular view of the different rock-groups and those subdivisions which are generally recognized as occurring in the county of Rutland. Period Pleistocene Jurassic Formation Postglacial Glacial. Lower Oolites Lias Great Oolite Inferior Oolite ' Upper Middle. ., Lower Character of the Strata Approximate thickness in feet River alluvium, Valley-gravel Boulder-clays, Gravels anc s to 20 1 sands up to 200 rCornbrash .... about 15 15 to 30 about 20 Great Oolite Clays Great Oolite Limestone. , Upper Estuarine Beds. Lincolnshire Limestone 20 to 30 up to 80 .Northampton Sands. up to 30 Clays and Limestones. about 180 JMarlstone Rock. . Clays and Sands. . Clays 100 to 150 about 800 The main physical features of the county of Rutland, as also of the adjoining areas to the north and south of it, are due to the sculpturing action of rain and running water operating on an inclined series of rocks which vary in hardness and in the capacity of resisting such erosion. It is safe to say that if the rocks were not so diverse in lithological char- acters, or if they were not inclined to the east, the physical features of the country would have been different. The most resistant rocks in the suc- cession above given are the Marlstone Rock, the Northampton Sands and the Lincolnshire Limestone ; these form two ridges with steep slopes or escarpments which run nearly north and south through the counties of Northampton, Rutland and Lincoln. Very little of the outer or Marlstone ridge comes within the limits of Rutland, but the escarpment of the Inferior Oolite runs through the middle of the county, though crossed and broken through by the valley of the Welland and those of its tribu- tary streams. Some isolated hills are formed by tracts of Great Oolite or by patches of Boulder-Clay. THE LOWER AND MIDDLE LIAS The oldest tormation which comes to the surface in Rutland is the clay of the Lower Lias, but this is only found over a small tract in the 2