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Solway glaciers lay in the direction of the Irish Sea on the one 

 hand, and on the other, eastwards across the lowlands bordering 

 the upper parts of the Solway, over the Bewcastle Fells and into 

 the Tyne Valley, and, yet again, up the lowlands of Edenside in 

 the direction of Penrith, Appleby, and Stainmoor. So that at the 

 climax of the Glacial Period the movements of the several ice 

 streams flowing into the Solway were first arrested, and then were 

 turned into directions different from any they had taken before — 

 in some cases in directions diametrically opposite to those they 

 would have taken had the Great Northern Barrier not advanced as 

 far southwards as the Scottish coasts. The evidence seems to 

 favour the view that it was mainly the uppei currents of the flowing 

 sea of ice that were turned inland in this way : the lower strata — 

 more influenced by local causes than the ice at higher levels — 

 may, all through the Glacial Period, have flowed more or less in 

 the usual directions, where those directions happened to coincide 

 with the lines of least resistance under the various directions of 

 pressure. In the original papers I have referred to, evidence was 

 given to shew that the upper surface of the inland ice in the 

 northern parts of Westmorland and Cumberland rose to an elevation 

 of over 2400 feet above the level of the sea : perhaps it would be 

 within the mark to say that it rose to a level of over 2600 feet. It 

 must therefore be obvious that the upper limit of the dam that 

 ponded back the ice about the Solway and compelled its upper 

 currents to flow inland must have exceeded even that great thick- 

 ness. And here I would remark that the above observations 

 relating to the Great Northern Barrier of ice are not intended to 

 suggest that the ice of every part of that barrier emanated from 

 Polar regions. I do not, and never did, believe in the southward 

 march of a great sheet of ice over everything in its way. But I 

 do believe that the outward flow of most of the ice originating in 

 the north-western parts of the kingdom was impeded, or else turned 

 in southerly directions by ice filling up the North Atlantic ; and 

 that the local ice so turned southwards acted in its turn as a 

 northern, or north-western, barrier upon other local streams further 

 south still, and so on, southward to the line where the southward 



