162 Proceedings of the Royal Irish Academy. 



masses of natural masonry of wMch. the coast is constructed. Malin 

 More headland, formed of tough schistose rocks, though not very lofty, 

 seems to have heen ahle to resist the force of the waves better than 

 the cjiffs of quartzite, as it projects much fui'ther out into the ocean, 

 than the adjoining parts formed of the latter rock ; and the same 

 statement holds good with reference to the promontory of Malin Beg 

 to the southward. This headland is, however, somewhat protected by 

 the group of islands formed of felstone porphyry, of which Eathlin 

 O'Birne Island is the largest. All along this part of the coast the 

 rocks are fissured, faulted, and thrown into numerous sharp folds. 



" From Eossarrell Point, as we proceed southwards, the coast 

 cliffs retreat inwards, and gradually become more and more lofty and 

 precipitous till they culminate in that magnificent wall of natural 

 masonry, which descends from the summit of Slieve League to the 

 siu'face of the ocean, through a height of nearly 2000 feet, and 

 stretches in an unbroken sweep from north-west to south-east through 

 a distance of about three miles. The greatest elevation of this 

 stupendous cliff occurs immediately below the summit of the mountain, 

 which reaches a height of 1972 feet, though here the actual cliff 

 is only 1650 feet in depth, the remaining part consisting of slopes; 

 and from this the crest gradually descends in either direction, till at 

 Bunglass Bay, near the southern extremity, the cliff is about 1000 feet 

 in height. The cliff is formed of successive coui'ses of quartzite and 

 schist, variously coloured, yellow, red, and gray, with a gentle dip 

 southward, or rather towards the south-east, along the northern and 

 central part of the escarpment, but becoming highly inclined and even 

 vertical, where the bay sweeps round to the west at Bunglass, where 

 it is sui-mounted by the cliff called ' The Eagle's Nest.' " 



(p. 11.) — "At the base of the vertical cliffs of Bunglass Bay a 

 shelving shingle beach slopes downwards into deep water ; and, stand- 

 ing on the edge of the cliff, you look down into the clear green waters 

 of the ocean from an elevation of 800 feet, and again upwards to the 

 cliffs above, rising to a similar height. This great sea-wall of meta- 

 morphosed strata has attained its present dimensions, both in length 

 and altitude, by the gradual undermining of the base, where the surf 

 is always breaking, and against which, diu-ing storms, the waves 

 beat with terrific force, as exposed to the full sweep of the Atlantic 

 waters. It would appear from the position of the summit of the 

 mountain immediately over the cliff, and from the direction of the 

 contour lines, as shown in the map, that the cliff has now reached its 

 maximum of elevation. "When the work of excavation has proceeded 



