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 A HISTORY OF DERBYSHIRE and massive variety called alabaster, which is capable of being sculptured, is obtained at Chellaston. The Lower Keuper Sandstone series consists of laminated micaceous sandstones, intercalated with beds of red marl. Under these are beds of sandstone, breccia and a conglomerate with red marls. In this district the lowest beds are generally a band of red clay or marl. The term Waterstones applied to these sandstones origi- nated from their watered-silk-like appearance, though now it is used to denote their water bearing qualities, which are due to the alternation of sandstones and marls. We have seen that the Permian rocks are unconformable with the Coal Measures. The Keuper beds were deposited unconformably on the more or less tilted and denuded edges of the carboniferous rocks. They cover in one place the Millstone Grit, in another the Yoredale Rocks and in another the Mountain Limestone ; and in the neighbourhood of Charnwood Forest rest on still older rocks. Hence before the Keuper period earth movements took place which raised the Palaeozoic rocks and exposed them to denudation. PLEISTOCENE SOUTH OF THE PENNINE CHAIN The deposits of the Pleistocene or Glacial Period consist of clays, sands and gravels resting unconformably upon the rocks which form the solid floor of the country. This mantle of drift is almost continuous from the northern part of our country to the Midlands, where it dies away into ordinary sands and gravels and disappears before we reach the Thames valley. The drift varies locally in character, and is generally composed of masses of clay, sand and gravel, with or without any signs of stratification. Boulders which vary considerably in size and character are often found embedded in the clay. Some of them consist of rocks derived from the district, others are foreign to it and must have travelled hundreds of miles from the places where they were once in situ. These boulders are frequently scratched, grooved and polished as if they had been pressed and rubbed against the rocks of the country over which they have passed. Often when the rocky floor is laid bare by the re- moval of the clay by which it has been overlain, it has been found to be covered with scratches and grooves whose bearings indicate the direction from which the boulders and clay have been brought. At present very little information has been published about the glacial deposits of the uplands of Derbyshire, but those of the Trent basin have received a considerable amount of attention. Mr. Deeley, after some years' work, gave in 1886 a general description and classifica- tion of the Pleistocene deposits which occur south of the Pennine Chain. The following information is abstracted from his paper. The deposits consist of Boulder Clays, gravels and sands of various kinds and ages. They vary very much in thickness, and are most greatly developed on the plains to the south and east of the Pennine axis. The oldest Pleisto- 28