184 



can ascertain, never as a whole been depressed below that level 

 a^ain. I do not think, however, that in this post-cretaceous 

 ■uplift the elevation of the various beds Avas to anything like 

 their present altitude, though the land surface of that period may 

 have stood out above the sea to an even greater height. There 

 has, of course, lieen an enormous amount of denudation since that 

 time. 



When this denudation had gone on during the whole of 

 Eocene and Oligocene time, the district had apparently been 

 reduced almost to the base level of erosion. A more or less flat 

 surface had been formed — what it is the fashion of the day to call 

 a " peneplain," — and though the word is an objectionalile one it is 

 very convenient. 



Then came what has been called the " Great Miot^ene 

 Upheaval," which affected the whole of "Western Europe. It is 

 not certain, however, that this upheaval took place during 

 Miocene time. This uplift raised the district as a whole, but in 

 particular ridged uii the " penei)lain " locally by a previously 

 existiu" axis of uplift running from Ingleby Greenhow to Robin 

 Hood's Bay, and so gave us what has been termed the " Moorland 

 Anticlinal." During the latter part of the Pliocene period there 

 was a movement of subsidence. Immediately before the Ice Age, 

 the land must have stood at least 170 feet higher than at present, 

 but Mr. Kendall finds no evidence in the district of an interglacial 

 submergence — indeed he finds no evidence of interglacial jjcriods 

 at all. 



It appears probable that there was at least a local de]n-cssion 

 to the extent of ;30 feet after the ice had retreated, for my friend, 

 Dr. Veitch, has called attention to a raised beach at Saltburn, 

 which must be post-glacial. Tlie land has risen since sufficiently 

 to reveal this beach, and there is some indication of minor 

 subsequent oscillations. 



When the post-cretaceous uplift took place, the axis of 

 uplift being, as I have said, in the line of the Pennines, there 

 -would be a gradual slope of the surface from the flanks of the 

 Pennine Chain eastward, or rather south-eastward, and upon it a 

 .series of rivers would be initiated, which would flow with a more 

 or less sinuous but persistent course from the watershed to the 

 coast. Such primary rivers, establishing themselves upon an 

 uplifted area, have been termed by Mr. W. M. Davis 

 '' consequent " rivers. These rivers follow the " dip " of the 

 beds, and cut their way through hard and soft strata alike, the 



