Dir IfOrETl — ON THE SOUTH OF IRELAND. 



247 



suppose that its origin is twofold : first, attributable to the sea-cur- 

 reut, and then that of the river which flowed out of this glen, and of 

 which it is the delta ; and secondly, of the glacier, which eventually 

 blocked up this mountain gorge, when the land had been sufficiently 

 elevated and the climate favourable for the formation of such pheno- 

 mena. 



The innermost semicircular mound is, therefore, most probably 

 the true moraine of the glacier; it measures 700 yards in length by 

 about 150 yards in width ; its height above the sea in its central 

 part where it is bisected by the Eiver Loe being 224 feet, and where 

 it is escarped by the stream to the depth of 85 feet, without the rock 

 being exposed. 



As the climate became less and less favourable for its formation, 

 the glacier lessened in width and receded, and the rubbish brought 

 down by it also decreased in amount, and it appears that the glacier 

 ceased to be formed when its termination rested at a height of 800 

 feet above the sea, as its debris is found at that height on the north- 

 ern flank of Tomics Eock. 



Throughout the entire extent of the Gap of Dunloe many of the 

 rock-bosses along the precipitous flanks of Purple Mountain, and at 

 the end of the Reeks on the western side of the gorge are rounded and 

 striated, the striae being all parallel to the length of the Gap, or about 

 JN". and S. 



Over many rock-surfaces along the shores at the head of Glen- 

 garifi" Bay, the glacial striae are well developed within a few yards 

 of the sea-level. This is important, as it proves that the temperature 

 of the sea and climate was Arctic after the country had assumed its 

 present physical features. 



On the northern flanks of the Tralee range of mountains, which ter- 

 minate in the summit of Caherconree, and at the mouths of the Glens 

 of Bartugaum and Derrymore there are exceedingly well-marked small 

 moraines, cut through by the streams which issue from these glens, 

 and which escarp them to the depth of from 30 to 50 feet. 



Glacial striae are observed in both these gorges, and in many 

 places the Old Bed Sandstone rocks are polished, rounded, and fur- 

 rowed in the direction of the length of the glens, or N. and S. 



The moraines are merely single semicircular mounds, measuring 

 nearly half a mile from end to end, where they rest on the flank of 

 the mountain, and having a width of fully a quarter of a mile. 



Over the rocky promontory in the coimty of Cork, formed by Dun- 



