466 ME. E. M. DEELEY OliT THE PLEISTOCENE 



thirtj^-nve feet. The sand is clean, stratified, and current-bedded, 

 the more gravelly beds containing flints and shell-fragments. 



At Keel, south of the Silverdale Pass, on the watershed, and 

 again in the pass itself, at Little Madeley, the same gravel is exposed. 

 At Little Madeley it is eight or nine feet thick, contains sand-beds 

 and rests upon sand. It contains numerous Palaeozoic pebbles, 

 flints, and shell-fragments. 



Sections in similar gravel have been opened out near Eccleshall. 



The sand and gravel with shell-fragments and flints occurring 

 below the Boulder-clay at Wolverhampton, I also regard as Chalky 

 Gravel. 



Eeferring to these deposits, the Kev. W. S. Symonds says * : — 

 "There are fossiliferous sands and gravels near Bushbury Hill, 

 which were excavated during the railway-cuttings, and from which 

 the Eev. "W. Lister obtained a series of shells similar to those 

 obtained by Mr. Marr near Buildwas, on the Severn. Among them 

 were Astarte arctica, Cyprina islandica, Nassa^ TurriteTla, Purpura^ 

 and many others common to our British Seas." 



lY. J^EWER Pleistocene Epoch. 



1. Interglacial River-gravel. 



2. Later Pennine Boulder-clay. 



The evidence furnished by the deposits of the two previous epochs 

 favours the assumption that, up to the close of Middle Pleistocene 

 times, the area under consideration was uninterruptedly submerged 

 to a greater or less extent. "We have have also seen that during 

 the Older Pleistocene epoch the glaciers originated in our British 

 hills ; whereas during the succeeding epoch they advanced over the 

 country from the north-east almost regardless of local contour. If 

 any interruption did occur in this submergence it was in the interval 

 which separated these two series. 



The deposits of Newer Pleistocene age now to be considered 

 indicate the first signs of subaerial erosion and the consequent 

 formation of river-gravel, a state of things which has, with the 

 interpolation of one or perhaps more cold periods, existed to the 

 present day. 



During this stage the rivers cut down their valleys through the 

 older Boulder-clays and sands to within about twenty feet of their 

 present depths, and left their gravels stranded as terraces at various 

 heights above their present courses. 



Upon these interglacial gravels, or upon the older rocks, there 

 frequently rests a Boulder-clay, sometimes reaching a considerable 

 thickness. The rock it rests upon is always much contorted or 

 broken. Unlike the earlier Boulder-clay it is conformable to the 

 surface-features produced by the subaerial erosion of the previous 

 stage. The direction of the ice-flow and the nature of the erratics 



* Records of the Rocks. 



