24 T. F. Jamieson — Raked Beaches of Scotland. 



glacier when it reached the coast. A submergence to the extent of 

 100 feet should surely have made some impression on these also. 

 It was no small development of ice that brought the glacier of the 

 Dee down to the coast when it left these moraines. During this last 

 glaciation I believe the whole of Scotland was more or less covered 

 with perennial snow and ice ; but the ice was probably very thin 

 in many places along the east side, where the thick streams 

 descending from the Highland valleys had room to spread out 

 freely. This would account for considerable portions of the older 

 clay-beds having escaped destruction, and in point of fact some of 

 these Belhelvie moraines overlie wasted masses of the clay. 



If there was a raised beach at 100 feet we ought to find beds of 

 estuary-mud with its characteristic fossils in our wider valleys 

 near the 100 feet contour - line, but where are they ? We have 

 such beds with shells and whale - skeletons in these valleys at 

 heights corresponding to the real old beach whose existence I have 

 mentioned ; but we have absolutely nothing of the sort corresponding 

 to a submergence of 100 or even 50 feet. Is not this sufficient proof 

 that there has been no such submergence? In Aberdeenshire the 

 river Ythan (which enters the sea half-way between Aberdeen and ■ 

 Peterhead) flows along a wide little valley with a very small gradient, 

 so that a submergence to the extent of 50 feet would send the tide 

 ten miles up it. That basin should have certainly been filled to 

 some extent with estuary silt, but no trace of anything of the sort is 

 to be seen beyond a few feet above the limit of spring tides. A like 

 submergence in the valley of the Dee would have sent the tide six 

 or seven miles up that river with a similar result, and a submergence 

 to the extent of 100 feet would have sent it on a few miles further ; 

 but no sign can be perceived of any such event having happened 

 after the last glaciation which brought the Dee glacier down to the 

 coast. Evidence of this sort could be multiplied along valleys on 

 the east side of Scotland, but perhaps the above will suffice. 



It would surely be time enough to talk of a hundred feet beach 

 when we could point to some beds of littoral shells at a corresponding 

 height, taking care that no shell heaps of edible mollusks left by 

 man were mistaken for the real article, because on the shores of our 

 estuaries such heaps are often to be found. 



The notion of raised beaches at 50 and 100 feet Seems to have 

 arisen in 1879 in mapping Sheet 31 by the Geological Survey, for it 

 is in the explanatory memoir of that sheet that we find this idea first 

 brought forward, and ever since then it seems to have become 

 a settled article of faith with the Scottish Survey. Beds of clay in 

 the neighbourhood of Falkirk are described in that memoir having 

 a flattish terraced aspect, which seems to have led to the belief that 

 they were old beaches ; but no good evidence, fossil or otherwise, 

 is adduced to substantiate this opinion, and surely the mere flatness 

 of a bed of clay is no sufficient proof that it is a beach. This clay 

 was no doubt accumulated under water, possibly sea-water, but the 

 evidence of denudation and disturbance which it shows in many 

 places harmonizes better with the idea that it has been afterwards 



