ANCIENT GLACIERS IN EASTERN HEMISPHERE. 157 



When the valley-glaciers reached the sea they suffered the 

 deflection which has been mentioned, partly as the result 

 of the interference of ice from the east of Scotland, but 

 also influenced directly by the cause which operated upon 

 the Scottish ice and gave direction to it — that is, the im- 

 pact of a great glacier from Scandinavia, which almost 

 filled the North Sea, and turned in the eastward-flowing 

 ice upon the British coast. 



" It is easy to see how this pressure must have forced the 

 glacier-ice against the Yorkshire coast, but vertical chalk 

 cliffs 400 feet in height are not readily surmounted by ice 

 of any thickness, however great, and so it coasted along 

 and discharged its lateral moraine upon the cliff-tops. As 

 the cliffs diminished in height we find the moraine farther 

 inland, and, as I have pointed out, the ice completely over- 

 rode Flamborough Head. Amongst the boulders at Flam- 

 borough are many of Shap granite, a few Galloway gran- 

 ites, a profusion of Carboniferous rocks, brought by the 

 Tyne branch of the Sol way Glacier as well as by that of 

 Stainmoor, and, besides many torn from the cliffs of York- 

 shire, a few examples of unquestionable Scandinavian rocks, 

 such as the well-known Rhoiriben-porphyr. It is impor- 

 tant to note that about ten to twenty miles from the York- 

 shire coast there is a tract of sea-bottom called by trawl- 

 ers ' the rough ground,' in allusion to the fact that it 

 is strewn with large boulders, amongst which are many of 

 Shap granite. This probably represents a moraine of the 

 Teesdale Glacier, laid down at a time when the Scandi- 

 navian Glacier was not at its greatest development. 



" On the south side of Flamborough Head the ' buried 

 cliff ' previously alluded to occurs. The configuration of 

 the country shows — and the conclusion is established by 

 numerous deep-borings — that the pre-glacial coast-line 

 takes a great sweep inland from here, and that the plain 

 of Holderness is the result of the banking-up of an im- 

 mense thickness of glacial debris. In the whole country 



