F. R. Coioper Reed — Corries of Comeragh Mountains. 229 



whole floor of the corrie from one precipice to the other with no 

 ievel ground round its edges. The eastern end of the lake is 

 obviously shallow, but local report credits the middle with being of 

 great or even unfathomable depth. No accurate soundings are, 

 however, on record, so far as I know. 



The existence of morainic dams across the mouth of the cwm is 

 strikingly apparent to any casual observer, and on ascending from 

 the level of the high road up to the lake three distinct transverse 

 moraines may be recognised. The lowest has a steep but irregular 

 face, and its surface forms a more or less level broad shelf, across 

 which meander many small streams. Huge angular masses of rock 

 and more or less rounded boulders are scattered over it, and several 

 examples of perched blocks — all of red sandstone or conglomerate — 

 are noticeable. At a level of about 800 feet there is another and 

 well-marked step in the slope, which indicates that we have reached 

 the face of the second moraine. The face is steep and rough, and 

 many springs issue from its foot or at various levels on the slope. 

 We then cross its somewhat irregular surface, which is of less width 

 than the lower one, and as we draw near the lake meet with a series 

 of large and overlapping mounds of morainic material and irregularly 

 distributed large boulders, which form the final barrier and dam 

 to the waters of the lake. The maximum height of these mounds 

 is about 100 feet above the level of the water. The stream 

 which issues from the lake runs between them near the southern 

 spur of the mountain, and expands into several small pools before 

 descending the steeper slopes of the moraines or soaking through 

 them to reappear as springs at a lower level. Its course at first 

 is certainly not over solid rock, and it is clear that the mouth of the 

 corrie is at any rate to a large extent filled up with drift. Its 

 resemblance to a ' hanging valley ' is well seen from the opposite 

 slopes of Croghaun Hill (PI. XIII, Fig. 2). 



South of Coumshingaun there is another large corrie in the face ot 

 the escarpment looking east and measuring about 850 yards in depth 

 and 600 in width. Though possessing less striking surroundings 

 than Coumshingaun and devoid of a lake on its floor it is essentially 

 of the same character, and the mouth is similarly blocked with 

 transverse moraines. The floor of it is almost entirely occupied 

 with extensive screes which slope down from the cliffs around it and 

 may have filled up a pre-existing lake. A stream issues from this 

 corrie and flows in a south-easterly direction to join the River Mahon 

 after a course of about 4 miles. There is no other definite corrie in 

 this escarpment, but about 21- miles to the west of it on the southern 

 slopes of the mountains, and only separated from the great corrie of 

 the Stilloges in the Nier Valley by a narrow ridge 300 yards wide 

 and just 2,350 feet high, there is a wide shallow amphitheatre formed 

 by a gentljf curved line of cliffs, about 750 yards long, beneath 

 which lie two small lakelets, from which issues the Coum Tay stream 

 joining the River Tay below. 



We may now turn to the Nier Valley, which possesses some 

 striking elongated corries or rather precipitously walled hanging 



