3 1 8 Chalk Escarpment and Eocene Outliers. 



succession all the outcrops of the different Oolitic for- 

 mations (some of the limestones of which, overlying beds 

 of clay, form minor scarps), we come to a second grand 

 escarpment (11, fig. 57), formed of the Chalk, which in 

 its day also spread far to the west, covering unconform- 

 ably the half-denuded Oolites, till it also abutted upon 

 the ancient land formed of the Paleozoic strata of 

 Wales, and by-and-by, as that land sunk in the sea, 

 buried it in places altogether. After consolidation 

 and emergence, this Chalk formation also suffered 

 great waste, and the result is this second bold escarp- 

 ment also facing westerly, which stretches from Dorset- 

 shire on the south coast of England into Yorkshire 

 north of Flamborough Head. Occasional outlying 

 patches of the Cretaceous formations attest its earlier 

 western extension in the south-west of England, and the 

 same overlap may be inferred with justice respecting 

 the relations of the Oolitic, Triassic, and Upper Cre- 

 taceous strata throughout the length and breath of 

 England. (See fig. 59, p. 313.) 



The Eocene strata, which lie above the Chalk, in 

 their day also extended much farther to the west, because 

 here and there, near the extreme edge of the escarpment 

 of Chalk, we find outlying Eocene fragments, and potholes 

 more or less filled with the relics of Eocene strata. On 

 the opposite page there is *a drawing of such potholes 

 filled with relics of the Plastic Clay of the Woolwich and 

 Reading beds, which in and round Savernake Forest 

 generally overlie the Chalk in a mere thin covering of 

 red and mottled clay and yellow sand, often mixed with 

 a few rounded flint pebbles. On the top of all there is 

 frequently a layer of semi-angular high level gravel, 

 and all of these have been more or less let down into 

 the potholes, by the dissolving of the underlying chalk 



