COLE : ORIGIN AND FORMATION OF WOLD DALES. 133 
It must not, however, be overlooked that, though ice 
stamped its mark upon existing depressions, so as to enlarge, 
deepen, and curve them, and to fix, as it were, the present 
formation, ice did not initiate the depressions. They were 
there before. 
We have not yet reached the origin of the dales, though 
we have learnt something as to their formation. JNor have 
we quite exhausted this latter subject : we have not taken 
into sufficient account marine action. 
It is fair to presume that, as a sheet of almost continental 
ice covered the whole of the north of England at the glacial 
epoch, the land as it sank, during the subsequent sub- 
mergence, was little affected, if at all, by the action of the 
sea; land and ice went down together. But on its re- 
emergence, though still in Arctic conditions, waves and 
currents, with floating ice, must have exercised some influence 
on the land-locked fjords of the Yorkshire Wolds. It is to 
this period that I assign the formation of the beaches already 
alluded to. 
To come back, however, to the origin of the dales, the 
depressions, whether shallow or moderately deep, were un- 
doubtedly in the line of the present valleys before the glacial 
epoch set in. 
What ivas their origin ? 
Before we can answer this question in any degree satis- 
factorily, we must go back throughout and beyond all 
Tertiary times to the deposition of the chalk itself. 
Chalk was confessedly deposited in at least a moderately 
deep sea. That portion of its area with which we are now 
specially concerned was deposited on an ancient [anticlinal] 
denuded axis, as is proved by the fact that the chalk at 
Wharram, Wharram Percy, Burdale, and Thixendale, rests 
on Kimmeridge or Speeton clay, whereas within a few miles 
distant, as at Huggate, Millington, and Warter, it rests on 
