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IX. 



THE DISCOVERY OF TWO CARBONIFEROUS OUTLIERS 

 ON SLIEVE LEAGUE, CO. DONEGAL. By J. R. 

 KILROE, H. M. Geological Survey. 



[Read February 14, 1888.] 



I am not aware that any notice has been published of the existence 

 of Carboniferous rocks in the Glencolombkille district ; and as their 

 discovery there possesses considerable geological interest, I am 

 permitted, through the courtesy of the Director- General and Director 

 of H. M. Geological Survey, to describe two outliers which repose 

 unconformably on the rocks forming the mass of Slieve League. 

 This mountain is already well known to those who have paid a 

 holiday visit to the village of Carrick, situated at the base of the 

 hill. Few visit the place without making an ascent, which may be 

 easily done by a good bridle path, through a glen on its east side ' r 

 or along the more circuitous route by Bunglass, where the tedium 

 of the climb will be compensated by an impressive view of Slieve 

 League Cliff, the finest sea-face in the British Isles. For any 

 not acquainted with the locality, it may be further stated that 

 Slieve League forms a bold feature in the mountain scenery of 

 West Donegal. Rising upward from Teelin Harbour on the east 

 to a height of 1972 feet, it overlooks the hilly tract forming the 

 promontory which stretches westward between Donegal Bay on 

 the south, and Loughros Bay on the north, and stands on the 

 southern shore of this promontory. The cliff is thus washed at its 

 base by the Atlantic breakers, and rises almost sheer to the 

 trigonometrical station on the summit of the hill. 



Two fine corries, with embosomed loughlets, divide Slieve 

 League into separate limbs, connected with a central mass by colls. 

 The western limb attains the greatest elevation and overlooks the 

 central mass by some eighty feet. Two of these colls are narrow 

 edges, where the sea-face meets the steep wall of either corry — 

 each being known as " The One-man's-pass." A third coll over- 

 looks the corries north-west and south-east. Seen from some 



