488 PROCEEDINGS OF THE GEOLOGICAL SOCIETY, [June 19, 



flux and reflux of the tide." He also speaks of the direction in which 

 blocks have been transported agreeing with the scratches on the rocks 

 beneath. At p. 249, he says, "There are phenomena which point 

 to the probability at least that enormous waves with vast carrying 

 force must have swept over the surface of the island. The general 

 appearance of its eastern, as compared with its western side, described 

 by Swedish naturalists under the term Stossseite or weathered side, 

 indicates in some measure that fact, and also the direction of that 

 action. But the evidence which tends most powerfully to the estab- 

 lishment of such a view is to be read in the phenomena presented 

 to us on the western side of South Barrule. We have noticed 

 there on its western side, and even within a hundred feet of its 

 summit, large boulders of the same granite which is developed on its 

 eastern side more than 600 feet below the summit, No simple 

 carrying-action of icebergs can have transported these blocks np the 

 very steep eastern face of the mountain, and so over to the other 

 side ; but we can imagine the extraordinary action of great waves 

 acting on masses of ice charged with these granitic blocks and 

 bearing them to a considerable elevation above the then sea-level, 

 "We must either grant this, or suppose an elevation of the mountain- 

 chain to the westward of the granitic boss since the deposit of the 

 blocks on the top and western side of South Barrule ; but of such ele- 

 vation no independent evidence has been yet discovered." So far Mr. 

 Gumming. This was published in 1848 ; and though the conclusions 

 drawn from the facts are a little out of date, there can be no doubt 

 of the accuracy of his observation of the facts ; and none of his facts, 

 so far as my knowledge goes, are antagonistic to the former exist- 

 ence of a great ice-sheet filling up what is now the Irish Sea, between 

 the Lake-district and the Isle of Man, and passing over that island. 



If now we pass on to South Lancashire and Cheshire, we may 

 take the evidence of Mr. Morton as to the glaciation of the basin 

 of the Mersey, In a paper read to the British Association at Liver- 

 pool in 1870, he modified his former views as to the scratches which 

 he had discovered being due to a glacier, and having found fresh 

 localities where these existed at some height above the bottom of 

 the valley both on the Cheshire and Lancashire side of the Mersey, 

 attributed them to an ice-sheet working down the Mersey valley to 

 the K.W. The exact direction of the scratches is N. 35 W. ; and they 

 are covered by Lake-district debris in Boulder-clay. The scratches 

 Mr. Morton supposes to have been made by the ice-sheet before 

 a submergence, during whch they were covered up by Boulder-clay 

 brought from the north by floating ice. 



It will be seen that these scratches were nearly parallel to, only a 

 little more easterly than, those along the Lancashire coast further 

 north, and coincide with the general southern glaciation of North 

 Lancashire. One thing is certain, that if the ice-sheet was working 

 to the S.S.E. in North Lancashii-e it could not be working to the 

 N,W. in South Lancashire. I would suggest that here too there was a 

 general movement of the ice-sheet from the Lake-district, and that 

 the low basin of the Mersey was one of the mouths by which the great 

 ice-basin now represented by the Irish Sea was discharging itself. 



