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 A HISTORY OF LEICESTERSHIRE portion of the great Trent basin. The nature of the Pleistocene succession in this area has been described by Mr. R. M. Deeley, who separated the beds into no less than eight sub-divisions l in the following order : Newer Pleistocene Epoch. Later Pennine Boulder-clay. Interglacial River-gravel. Middle Pleistocene Epoch. Chalky Gravel. Great Chalky Boulder-clay. Melton Sand. Older Pleistocene Epoch. Middle Pennine Boulder-clay. Quartzose Sand. Early Pennine Boulder-clay. Mr. Deeley drew his conclusions from a large number of isolated sections ; but the detailed mapping of the ground, which has since been undertaken, does not entirely bear out these ideas. The main fact drawn from the study of the Drifts is that they are of two distinct ages ; a lower one having its included fragments, consisting principally of quartzite pebbles and fragments derived from the west or north, and an upper one containing detritus of the Chalk and Oolites derived from the east. These occupy the relatively higher ground throughout the district, and appear to have formed one vast sheet rising gradually to the watershed, and falling equally gradually on the other side. This sheet, which seldom has a thickness of more than iooft., is cut through by all the principal streams of the district ; so that the solid strata are exposed in nearly all the valleys, while the Drift is found capping all the ridges between them. The greater part of this Drift is composed of Boulder-clay, but there are also large quantities of sand and gravel, which occur at various horizons in the clay, although principally between the two clays mentioned above, and also associated with the Chalky clay. The thickest deposits of gravel are in the southern part of the county around Lutterworth, in the neighbourhood of Market Bosworth, and on the higher ground about Tilton and Skeffington. The greatest elevation at which the Drift is found is on the Charnwood Hills, where it occurs slightly above the 600 contour line, and on Life Hill near Billesdon, where it rises to 730 ft., which is the highest ground in the neighbourhood, so that there is no evidence as to what its maximum elevation may have been. The Boulder-clay is thickest in the country to the south of Leicester ; it is also of considerable importance as far north as the high ground about Six Hills, but thins out to the north of the Charnwood Hills, and along the valley of the Trent, beyond which it soon disappears. The Drift occasionally contains large transported masses of Oolite, Chalk, and Marlstone, which appear to be the result of coast ice acting along the shore at a period when the country was partially submerged. One of these occurs to the north-west of Melton Mowbray. It is a mass of oolitic lime- stone ; and as far as can be made out from old quarries, and the fragments ' Quart. Journ. Geol. Soc. xlii, 437. 16