254. Scientific Proceedings, Royal Dublin Society. 



The rock -platform is cut across the edges of the highly inclined 

 black slates and sandstones of the Carboniferous Slate series. It 

 has a smooth, water-worn surface, sloping gently seaward, and at 

 its outer margin drops more or less steeply on to the modern 

 shore. It is raised about 5 feet above high-water mark of 

 ordinary spring-tides. 



The blocks which lie on the platform embedded in the beach- 

 sand sometimes attain a length of 10 feet. They are sub-angular, 

 and even rounded in form, and have obviously been subjected to 

 a certain amount of erosion by wave action. They are of similar 

 nature to the rocks in the pre-glacial cliff above, having fallen 

 from it during the formation of the beach. They probably mark 

 a period when undercutting of the cliff was still in progress. 



The raised-beach sand rests on the wave-worn platform, and 

 consists chiefly of small oval flakey bits of the local black slate, 

 lying flat, and cemented by oxides of iron (' ferrierete '). The 

 pebbles occur in rows in the sand ; all are well rounded, and most 

 of them consist of vein quartz. The whole deposit is well 

 stratified, and obviously water-sorted. 



The blown sand overlies the beach-gravel and blocks, and is 

 banked against the old rock-cliff, behind the head, which has 

 obviously slipped down little by little over it. ' The sand is 

 tolerably free from admixture of rubble. 



The lower head consists of fragments of black slate and 

 angular lumps of vein quartz. The slate fragments are all 

 perfectly angular, and are bounded by cleavage and joint planes. 

 Consequently the common shape is that of slabs or plates which 

 lie flat in the deposit, and impart a sort of rude stratification to 

 it when seen from a distance. 



The boulder-clay is a stiff, grey, unstratified clay, containing a 

 variety of stones which lie in all positions in it, and have been 

 derived from the Carboniferous Slate and Old Red Sandstone. 

 The boulders exhibit different degrees of rounding, and the 

 harder ones are often striated. 



The upper head is, like the lower, composed of angular slate 

 fragments, but also contains a small number of sub-angular and 

 rounded stones. 



A short distance from the section described above, a stack 



