CHAP. XIV.] SUMMARY OF GEOGRAPHICAL EVOLUTION. 309 



Cheshire and Lancashire across the Irish Sea, and north- 

 eastward on the other hand through Nottingham, Lincoln, 

 and York, far into what is now the bed of the North Sea, 

 while to the southward a basin which seems to have been 

 always more or less filled with water occupied the southern 

 part of England and the central area of the English 

 Channel. 



Between the two northern plains, and between the arms 

 of the great lake into which the low ground was subse- 

 quently converted, rose the mountain range which is now 

 known as the Pennine chain. This must have lifted its 

 crests and escarpments much higher above the flanking 

 low lands than it does at the present time ; we may sup- 

 pose that in those places where patches of the Lower Coal- 

 measures had escaped destruction and lay over the Mill- 

 stone grit the hills were nearly 2,000 feet higher than they 

 are now, that being the thickness of the grits and gan- 

 nister measures which once capped such table-lands as that 

 of the Peak country and Kinderscout. These hills may, 

 therefore, have risen to heights of between 3,000 and 4,000 

 feet above the surface of the plains. 



Northward then, as now, the Pennine range widened out 

 and was continuous with the Cheviots and the southern 

 uplands of Scotland, the hilly country being penetrated by 

 many deep valleys the lower parts of which afterwards 

 became inlets of the great salt lake. Whether the Scottish 

 lowlands were lowlands then we do not know, but the 

 Highlands were certainly part of a mountainous region in 

 the hollows of which other lakes came eventually to be 

 formed. 



To the westward of this central tract of country, with its 

 several lake-basins, lay a vast region of hills and 

 mountains, with possibly other plains and lakes, which 

 stretched westward into the Atlantic at least as far as the 

 present contour-line of 1,000 fathoms. Of this region 



