part 3] THE GLACIATION OF NORTH-EASTERjSr IRELAND. 407 



The eastern spur of Camlough Mountain, known as Bally- 

 macdermot, is cut by five dry channels at 920, 910 (in and out), 

 050, and 630 feet respectively. 



Between the village of Camlough and the reservoir the surface 

 is largely granite, but boulder-clay similar to that just described 

 occurs in patches ; and in the narrow part of the reservoir valley 

 at 500 feet is a cutting which shows rotten granite, covered by 

 about 3 feet of boulder-clay containing local rocks only. With 

 the exception of this small patch, the sides of the valley appear 

 to be free from drift ; but, on the west side of the reservoir, is a 

 long ridge of drift, running from north-west to south-east through 

 Aghmakane. 



On the eastern flank of Sugarloaf Hill is a dry channel falling- 

 southwards at 800 feet, and another between Sugarloaf Hill and 

 Courtney Mountain at 550 feet. 



The south-western spur of Slievenacappel is cut by three parallel 

 dry channels, all falling south-eastwards between the 600- and 

 700-foot contours. 



The mountain of Slieve Gullion (1894 feet O.D.) stands in the 

 centre of a great amphitheatre, and is separated from the walls of 

 the basin by valleys upwards of a mile wide. On the western 

 flanks of Slieve Gullion roches moutonnees occur at 400 feet, 

 a striated surface at 600 feet, and dry channels at 950 feet and 

 1200 feet respectively show that it was glaciated at least up to 

 the last-mentioned level. 



The valley that surrounds Slieve Gullion on the north-west, 

 Avest, and south-west, drained by the Forkill River, shows much 

 drift which contains mostly local and Silurian rocks. This drift 

 is arranged for the greater part in long mounds, which have their 

 axes north and south. 



East of the mountain is the great basin of Adavoyle, at a level 

 of between 300 and 400 feet, through which runs the main line of 

 the Great Northern Railway from Dublin to Belfast. Much of 

 the surface of the basin is covered by peat ; but drift-mounds 

 frecpiently show above its surface, and there are kettle-holes of 

 considerable dimensions near Drumintee and at Ballynamona. 



The basin is at present drained by three streams, the largest of 

 which is the Flurry River, flowing southwards through Ravensdale. 

 A smaller stream also flows southwards through the valley which 

 carries the railway, and the northern portion drains northwards 

 into Camlough Reservoir. 



The southern rim of the amphitheatre shows many roches 

 moutonnees and striated surfaces, all indicating a southward 

 flow, and is cut by four large gaps. The westernmost of these 

 is at Forkill (230 feet), and is occupied by the Forkill River. 

 It has the contours of a normal valley, but is very large in com- 

 parison with the size of the stream. 



The second is at a height of 380 feet, and lies half a mile 

 north-east of Forkill House. This is a deep gorge-like valley 

 cutting through the wall of the amphitheatre, and flanked by 

 Q.J. G. S. No. 315. 2f 



