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 GEOLOGY lington north-west of Uppingham, and being quarried in 1821 gave rise to the idea that the Chalk formation was actually present in Rutland/ Owing to the long continued erosion by rain and rivers to which the country has been exposed since the formation of the Boulder-Clay much of this material has been removed, and the portions which re- main appear as isolated tracts varying in size from a wide spreading area of more than 20 square miles to one of only a few hundred yards in length. One of the largest tracts of Boulder-Clay is that on the con- fines of Rutland and Leicestershire, and this tract is also instructive as showing the manner in which the pre-glacial surface of the country is draped by the Glacial Clay. It rises from the valley of the river Eye west of Melton Mowbray, and extends southward across the plain of the Lower Lias to the slopes of the Middle Lias between Pickwell and Whissendine ; climbing these it spreads over the high ground around Cold Overton, Knossington and Ouston Woods, and though it is cut through by the head waters of the river Gwash, tongues of it cap the ridges on each side of the Gwash valley as far as Gunthorpe on the northern side and Martinsthorpe on the southern side. East of Martins- thorpe it passes on to the Northampton Sands, and near Manton an isolated patch rests on the Lincolnshire Limestone. Still further east, by Edith Weston and Normanton, tracts of Boulder-Clay lie on the top of the Limestone escarpment, and finally on Bushey Closes (west of Ketton) another patch of it climbs to the top of the Great Oolite Limestone. Other spreads of Boulder-Clay occur in the northern part of the county, the largest of them extending in a very irregular manner from Empingham Wood by Stretton to the Morkery Woods and South Wit- ham. The contrast between the warm red soil of the Lincolnshire Limestone and the cold clay land with its numerous woods is very striking. A similar contrast presents itself near Uppingham, where the outlier of Northampton Sand is capped by Boulder-Clay on the ridge south-west of the town. Glacial Gravel and Sand. — These deposits are intimately associ- ated with the Boulder-Clay, occurring sometimes below it, sometimes as lenticular beds in the clay, and sometimes as patches which apparently overlie it, though some of these may be intercalated beds exposed by the removal of superjacent clay. The gravels consist of the same rocks as occur in the Boulder-Clay, rounded pieces of hard chalk being generally abundant, as also are flints and stones from Jurassic rocks ; of less common occurrence are Carboniferous rocks, and there are occasionally fragments of granite and other igneous rocks from the north of England. The gravel is generally rudely stratified, and the beds are sometimes bent up and contorted as if by the impact of ice. In some places they in- clude or pass into coarse reddish sand, which generally exhibits the phe- nomena of current bedding in a marked degree. ' See Lonsdale in Phil. Trans, vol. Ixxxi. pt. 2, p. 281 ; Fitton in Trans. Gcol. So:, ser. 2, vol. iv. pp. 308, 383. II