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 GEOLOGY Even the Bredon outlier of Inferior Oolite exhibits at the surface 30 or 40 feet of rubble. The rock, indeed, is irregularly weathered, and the resulting gravelly detritus contains in its midst isolated masses and pin- nacles of unweathered limestone. W. C. Lucy connected the distribution of the rubble w^ith soil- movements, the weathered rock slipping down the hill-sides during times of thaw after severe frost. In Witchell's opinion, this Rubble Drift was ' due to storm-waters or surface-drainage, which brought the detritus down the hill upon a frozen surface, and deposited it in those places where the frost usually disappeared in spring before it left the higher ground.' ' Both explanations may be to a certain extent true and they accord much better with the facts than does the explanation of Prestwich, whereby this Rubble Drift would be due to the effects of wide submergence.* At Church Honeybourne, east of Evesham, the Lower Lias Clay is contorted, and again at South Littleton the exposed beds of limestone and clay have been nipped up on the surface in a series of sharp folds. As far west as Croome d'Abitot, near Pershore, in Worcestershire, similar evi- dences of surface disturbance were observed.'* Probably the ' Lias clay with contorted beds of Lias limestone,' noted in the railway-cutting at Dunhampstead by Strickland in 1840, exhibited features of the same character. At Halford, north of Shipstou-on-Stour, the beds of White Lias are much disturbed in places. In this region, although the disturbances are similar to those pro- duced by glacial action, we have (with the exception of the Aston Magna Drift) no distinct evidence of Boulder Clay, the superficial deposit being a few feet of reddish-brown clay with pebbles of quartz and quartzite. This Drift occurs here and there over a wide area, and may be a result of the denudation of Boulder Clay. Near Birmingham, on the borders of Staffordshire and Worcestershire, there are abundant evidences of Boulder Clay and other Glacial Drifts. At Moseley and on Frankley Hill there are considerable beds of sand and gravel which belong to the Glacial period. Until the Drifts are separately mapped, it is impossible to deal adequately with the diverse deposits which are scattered over the surface of the country, for the most part in patches, although much has been written on the subject by Strickland, Brodie, W. C. Lucy, H. W. Cross- key, and others.* In the modern Alluvial deposits peaty layers are sometimes met with, and T. G. B. Lloyd noted a bed 8 feet thick, resting on gravel, at Chadbury. In it many antlers of red deer were found. The Alluvial clays have been used for brick-making, while the land in general forms fertile meadows and pasture. Oolitic Rocks of England, p. 462. ' H. B. Woodward, Jurassic Rocks of Britain, vol. iii. pp. 146, 150, 310. Soc, vol. ix. p. 116 ; also Proc. Geol. Assoc, vol. xv. p. 400. 25
 * Proc. Cotteswold Club, vol. v. p. 43 ; vol. vi. p. 150 ; and H. B. Woodward, Lower
 * Quart. "Journ. Geol. Soc, vol. xlviii. p. 314.
 * See W. J. Harrison, ' A Bibliography of Midland Glaciology,' Proc. Birmingham Phil.