88 SECTIONAL ADDRESSES 



Thirdly, there is no obvious connection between the present topo- 

 graphy and the First Welsh drifts, but in the case of the supposed Second 

 Welsh drifts, it is possible to see cases where the present drainage seems 

 to have been influenced by the glaciation, as for example the course of the 

 Blythe, as described by Miss Tomlinson. Again, in the Cole valley 

 sands and gravels referable to the Second Welsh glaciation prevent the 

 Cole reaching the Tame near Birmingham and send it six miles to the 

 east before it effects a confluence ; and in the Stour valley, as Mr. White- 

 head has pointed out to me, the present course through the Bells Mill 

 Gap in the Bunter Pebble Bed escarpment near Stourbridge can be 

 explained by assuming an ice-dam across the original Stour valley at 

 Hinksford. 



Finally, outwash material grades down into the valleys at levels which 

 accord with terraces that are far younger than the Woolridge Terrace and 

 therefore far younger than the First Welsh glaciation. One important 

 spread runs east of the Severn from near Stoulton southwards through 

 Wadborough and Besford to grade with Avon No. 5 Terrace, and there- 

 fore perhaps to be regarded as comparable in date with the Great Eastern 

 glaciation. Others follow the Salwarpe and Stour valleys, and are but 

 little above the level of the Kidderminster Terrace which itself correlates 

 approximately with the Second Interglacial epoch. 



Having stated some of the evidence for a Second Welsh ice-sheet in the 

 Midlands contemporary with the Great Eastern glacier when the latter 

 spread from the north-east into the Eastern Midlands and Avon vale, I 

 caii only briefly refer to its retreat. This is illustrated diagrammatically 

 on Fig. 5. 



The first position shown is indicated by a line with double offsets. This 

 line conforms with Miss Tomlinson's maximum ' re-advance ' in the 

 Blythe valley ; with the considerable development on the Ridgeway of 

 drifts with both north-eastern and north-western erratics which may 

 have owed their origin to the combined efforts of the two glaciers ; and 

 with the gravels and sands of the Stoulton-Besford area which I have just 

 referred to as grading to the same level as Avon No. 5 Terrace. As the 

 two sheets withdrew, the drainage down the Avon was responsible for 

 the formation of some parts of the same terrace. It appears necessary 

 to imagine the Severn valley from Worcester downwards as having already 

 been established, possibly as a marginal flow along the edge of the First 

 Welsh Glacier. 



The second stage deserves more elaboration ; but this cannot yet be 

 achieved, owing to want of data. The line indicated with three offsets 

 must therefore be regarded as a composite representation of several that 

 it would be necessary to draw in order to satisfy even the evidence we 

 now possess. East of Birmingham the line represents a lobe in the Tame 

 basin connecting near Tamworth with the Eastern ice of the Anker and 

 Trent valleys. This disposition of the two sheets would enable us to 

 account for the Blythe valley lake suggested in the Birmingham Memoir 

 and described by Miss Tomlinson. It drained southwards by the Kings- 



