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out all the drift left by the older ice, or to cut down to the solid rock 

 beneath. The drift that is left in the bottom of these valleys, and 

 the materials of the moraines themselves, consist, not of detritus 

 native to the part of the valley traversed by the little glacier, but 

 of the far-travelled material nearly identical in character with that 

 composing the bulk of the older sediment left by the ice sheet. 



Abrupt termination of the period of maximum glaciation. — Between 

 the commencement of the period of minor glaciation and the 

 close of the period characterised by the dispersal of Shap 

 Granite Boulders over Stainmoor, there appears to me to have 

 intervened a decidedly warm period, when little or no ice was 

 formed, and when the whole of the great mass of ice of the ice 

 sheet melted away on the spot. Judging by the character and 

 the direction of the glacial markings left in Edenside, the move- 

 ments of the ice sheet seem to have been brought somewhat 

 abruptly to a standstill, which was followed immediately by the 

 melting of the ice there and then as it stood, and the liberation of 

 its contents in the form of sediment on the spot. It looks very 

 much as if a change in the direction of flow of some of our great 

 ocean currents had been effected somewhat abruptly, and a corre- 

 spondingly abrupt amelioration of the climate of the North Atlantic 

 had at once ensued. The edge of the Great Northern Barrier 

 began to recede from our shores, and the local ice at once ceased 

 to move inland and uphill. The rate of melting of the winter 

 snows exceeded the supply, and no more new ice was formed. 

 The whole mass, as I have before said, melted as it stood ; and 

 the waning ice sheet did not pass in reverse order through the 

 series of changes that accompanied its increment. The form and 

 direction of the strise shew in the plainest and most unmistakeable 

 manner that it did not break up into a series of small glaciers ; on 

 the contrary, it is quite clear that the ice never moved after it had 

 attained its maximum development. I insisted much upon this 

 fact some years ago; but even yet its significance seems to have 

 been missed. 



