CHAP. XIII.] PLEISTOCENE EPOCH. 295 



North Sea where bones have been dredged, but Pleistocene 

 remains are not so abundant elsewhere. 



An elevation of the bed and borders of the North Sea to 

 the extent of 40 fathoms (240 feet) would now convert the 

 Dogger Bank and all the surrounding parts of the sea-bed 

 into land. The Rhine would make its way through the 

 upraised country, and the rivers of eastern England would 

 at once become its tributaries. A subsequent submergence 

 of 20 fathoms would convert the Dogger into an island 

 round which the currents would circulate as they do now, 

 and it is probably to this isolation of the plateau that the 

 preservation of the ossiferous gravels is due ; sandbanks 

 and beaches would be formed round its shores as it 

 gradually sank, and though the gravels would be re-distri- 

 buted, the larger stones, teeth, and bones would not be 

 destroyed, but would be scattered over the submerged 

 surfaces. It is indeed possible that some of the remains 

 are those of animals which were left on the island at the 

 time of its separation from the Continent, and were alive 

 when the final and complete submergence took place. 



By the phenomena of the Dogger Bank, therefore, we 

 are led to look back to a time when it was neither a bank 

 nor an island, but a portion of western Europe, its southern 

 and western sides being washed by the waters of a large 

 river, which drained a large region to the south of the 

 bank and flowed northwards along what is now the deeper 

 part of the North Sea. In point of fact, a consideration 

 of all the evidence brings us to the conclusion that the 

 North Sea had then no existence, and that the western 

 coast-line of Europe ran outside our islands somewhere 

 between the contour-lines of 40 and 100 fathoms. It was 

 the opinion of Godwin-Austen, De la Beche, Lyell, and 

 nearly all subsequent writers, that the 100-fathom contour 

 should be taken as the coast-line of this period, but there 

 is no proof that the elevation was quite so great, and in 



