Submergence. 415 



glacial striations, as if the materials, during the pro- 

 gress of submersion, had been derived from older 

 moraines, and, being water-worn by attrition on the 

 margin of the sea, the original sharpness of the scratches 

 had been well nigh obliterated. 



At various levels on the low ground between Caer- 

 narvon and Criccieth, on the north coast of Cardigan 

 Bay, there are extensive deposits of sand and gravel, 

 well stratified, and much resembling those of Moel Try- 

 faen, but in them I have not yet found sea-shells. 

 They are overlaid by boulder-beds, and the same is the 

 case with similar halt-consolidated strata on the sea-cliffs 

 of Anglesea at Lleiniog, and beyond, between Beaumaris 

 and Penmon near Puffin Island. 



Putting all these facts together I see no reason to 

 get rid of the hypotheses published by me in 1859, 1 

 that, as a slow submersion of the land took place, the 

 diminishing glaciers, still descending to the level of 

 the sea, deposited their moraine-rubbish there, which 

 matter was often remodelled by the waves to form sand 

 and gravel. Gradually sinking more and more, and 

 sufficient cold still continuing, the minor glaciers, de- 

 scending from groups of icy islands, entered the sea and 

 broke off in icebergs, which, as they melted, deposited 

 their stony freights on the sands and gravels that 

 more or less covered the bottom of the sea. 



To what depth this progressive submersion may have 

 reached I cannot say, but I think it cannot have been 

 less than from 1,200 to 1,500 feet. In corroboration of 

 this it is worthy of note that the Rev. Maxwell Close 

 has described sea-shells as occurring at the height of 

 1,300 feet on the Wicklow Hills. The features of the 



1 < Old Glaciers of North Wales, and Peaks, Passes, and Glaciers.' 



