458 Notices of Memoirs — British Association — 



It is surrounded by a marginal hill barrier, and has large hill 

 masses at Cannock Chase and the Clent region ; while it is crossed 

 by hill ranges from Bushbury to Barr Beacon, from Wolverhampton to 

 the Lickeys, and from Quinton to Birmingham. The surface is thus 

 divided into four interior basins, forming separate drainage areas. 

 Save for the exits from these basins, the margin is broken in two 

 places only. The chief physical feature is the possession of the 

 crucial portion of the Midland watershed, which runs across the 

 plateau from Wolverhampton to the Lickeys, and thence eastward 

 along the southern margin. 



Arterial drainage is supplied by the Trent and Severn, the former 

 draining five-sixths of the plateau, and the latter receiving only the 

 southward marginal drainage and that of the Stour basin. 



The eastern syncline is occupied by the Biver Blythe-Tame flowing 

 north. The watershed at the southern end of this valley has retreated 

 northwards for 4 miles in post-Glacial time. 



The western syncline was formerly drained towards the Dee, and 

 the head-waters of the Severn were originally around Kidderminster, 

 the Clent range being united with the Enville Hills further west. 

 The principal outlet towards the Dee was by the Church Eaton 

 Water, and the outlet into the Trent below Stafford not then in 

 existence. This syncline is now drained northward by the Penk 

 into the Sow and Tame, and southward by the Smestow-Stour into 

 the Severn. Stream piracy is manifest near Wolverhampton. 



Marginal streams are characterized by excessive activity, especially 

 southward, notable examples being the Arrow and the xllne. The 

 Arrow, however, represents the captured head-waters of an ancient 

 river flowing through the Moreton Gap into the Evenlode, the pirate 

 stream being the Warwickshire Avon, a strike river originally 

 confined to the country west of Evesham. The watershed then ran 

 southward from the Lickeys to the Cotswolds, being now represented 

 by a long, narrow promontory reaching into Evesham and by Bredon 

 Hill southward. Internal drainage is confined to the four basins. 

 The Cannock basin has now no trunk stream, its waters uniting near 

 the exit below Cannock to form the Saredon Brook. Glacial 

 modification is much in evidence, the south-eastern portion having 

 formed a lakelet with gorge-like overflow through Walsall. The 

 margin of this basin has twice been broached by marginal streams. 

 The Tame basin is triangular in shape and formed by the union of 

 two basins reaching back to pre-Triassic ages, a large buried stream- 

 course existing at Moxley, whilst a very great valley is traceable 

 upwards through Smethwick, Oldbury, and Blackheath. At this 

 point two buried stream-courses are found, each filled with material 

 transported from the Clent Hills. The inference is that this marked 

 the original source of the Trent, as the Upper Trent Yalley appears 

 to be of more recent date. 



The Stour basin is likewise a combination. Streams descend 

 south-west from Dudley to Stourbridge, and north-eastward from 

 Clent to Halesowen. They are united by a succession of gorges 

 4 miles in length. This basin is a remarkable instance of extreme 

 post-Glacial denudation to a depth of 300 feet. The Halesowen 



