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 A HISTORY OF WARWICKSHIRE south of Scotland and the Lake District ; it extended in the direction of Warwickshire as far south as Lichfield, and all along its terminal line notably in the neighbourhood of Wolverhampton are found great numbers of granite and other boulders. The third or North Sea Glacier issued from the North Sea, and part of it invaded the Yorkshire coast, passed over the Lincolnshire chalk country, and made its way inland to the high ground of Charnwood Forest. Here it seems to have divided to some extent into lobes ; one travelling southwards by Leicester and Rugby got as far as the valley of the Thames, while another made its way to the south-west into the Avon valley, leaving abundant traces in the form of chalk debris and pieces of flint scattered over the surface or embodied in its gravelly and clayey deposits even as far as the vicinity of Chipping Campden. 1 Traces of the debris carried by all these ice- flows have been met with in our district, though our knowledge of these deposits so far as Warwickshire is concerned is at present very incom- plete, for no one observer has investigated the whole of them, and their superficial limits have only very partially been determined. 2 We are therefore compelled to treat the subject more or less bibliographically. One of the earliest investigators was Buckland, 8 who noticed the abundance of gravel containing well rounded quartzite pebbles scattered over the surface of the Midlands at various localities extending eastwards and southwards of the Lickey district in north Worcestershire, particu- larly at Coleshill and along the Lias plain near Shipston-on-Stour. He traced these gravels down the Avon valley from Stratford to Evesham and thence eastwards by Kineton, with prolongations southwards along the Cherwell and Evenlode valleys. He recognized that these gravels were largely derived as he thought by the waters of the ' deluge ' from the Bunter pebble beds of the Trias. At the same time he recorded the occurrence of fragments of igneous and metamorphic rocks with chalk and chalk flints, while south-east of Shipston-on-Stour he noted pieces of red chalk like that of Lincolnshire. These early observations alone are sufficient to show that some form of transportive agency entered the district from two different directions : from the north-east, and from the north or north-west. Strickland 4 made some valuable observations on the drifts of the district ; he pointed out that they are divisible into several types : first is the quartzose drift which occurs on some of the hill tops, contains no mammalian remains, and was apparently derived from the north. The second or flinty type (equivalent probably to the chalky boulder clay) is very prevalent in the east of the county and near Rugby, extending thence along the base of the Oolite hills to the Vale of Shipston ; it covers some of the hills to a considerable depth, contains many chalk 1 See G. E. Gavey, Quart. Journ. Geol. Soc. ix. (1853), 29; also H. B. Woodward, Gcol, Mag. (1897), p. 485. For a very foil list of papers on this subject see 'A Bibliography of Midland Glaciology,' by Mr. W. J. Harrison in Prix. Birm. Nat. Hist, and Phil Soc. ix. (i 8<x) 1 16 5 Tram. Geol. Soc. v. (1821), 506. 24
 * Memoin of Hugh E. Strickland (8vo, Lond. 1858), p. 90.