On the Agricultural Geology of England and Wales. 465 



ments of this peculiar rock are found, accordinf^^ to Dr. Buckland^ 

 mixed with the Warwickshire gravel, S.E. of Shipston on-Stour, 

 and near Moreton in the Marsh, associated with pebbles of the 

 hard white chalk, which accompanies the red chalk in Yorkshire 

 and Lincolnshire. 



It has been already stated that this gravel of the midland counties 

 has crossed the oolitic ridge. The passage, like that of the Cum- 

 brian erratics, has been effected at the lowest points. One of these 

 is near Moreton in the Marsh. Deflected thence eastward, by the 

 elevated ridge of Stow on the Wold, the gravel has proceeded 

 : along the line of the Evenlode, where it joins that of the Thames, 

 four miles north-west of Oxford. Great accumulations of gravel, 

 containing pebbles of the Lickey quartz rock, not only cover ir- 

 regularly the lower regions of the valley of the Evenlode, but are 

 scattered abundantly over the oolitic strata, which form table- 

 lands of considerable height on both sides of it. Accumulations 

 of similar gravel rest on the insulated and almost conical sum- 

 mit of Wytham-hill and the ridge of Bagley-wood, exactly oppo- 

 site the confluence of the Evenlode with the Thames. In like 

 manner the quartzose gravel of Warwickshire has entered the 

 valley of the Cher well, through another gap in the oolitic escarp- 

 ment, and has passed onwards, mixed with chalk flints, and 

 slightly-rolled oolitic detritus, into the valley of the Thames. 

 Along the valley of the Thames the quartzose pebbles, in con- 

 tinually decreasing quantities, and mixed with the gravelly wreck 

 of each succeeding formation, have been traced to the gravel-pits 

 of Kensington and Hyde-park. They also accompany granitic 

 pebbles, in the flint gravel at Brentford, below the deposits con- 

 taining bones of elephants and other large mammals, with fresh- 

 water shells. 



The absence of the Warwickshire gravel from the valley of the 

 Windrush, separated from that of the Evenlode by the narrow 

 ridge of Stow on the Wold, and the local character of its gravel, 

 caused by the Windrush taking its rise within the elevated range 

 of the Cotswolds, and by there being no depression, or breach of 

 continuity, like those at the heads of the Evenlode and Cherwell, 

 through which the Warwickshire gravel entered their valleys, 

 prove the establishment of the present general features, near the 

 head-waters of the Thames, before the formation of those erratic 

 - deposits, and the influence of those features in determining the 

 distribution of the gravel ; but on the other hand,* Dr. Buckland, 

 who described these deposits in 1817, inferred — from the accu- 

 mulation of it upon Wytham-hill, Bagley-wood, Henley and 

 Cumnor hills, and on the highest summit of Wychwood-forest, as 



* Geol. Trans., First Series, vol. v. p. 521. 

 VOL. XII. 2 H 



