O'Reilly — On the Waste of the Coast of Ireland^ 8fc. 11.5 



sea makes great inroads on the clay-slates of Pitfel Head, on the 

 serpentine of Vord Hill, in Fetlar, and on the mica schists of the Eay 

 of Trieste, on the east coast of the same island, which decomposes into 

 angular blocks. The Quartz Rock, on the east of Walls, and the 

 gneiss and mica schist of Garthness sufier the same fate." 



(p. 511.) — Lyell says, under the heading ^^Destruction of Islands^' : 

 " Such devastation cannot be incessantly committed for thousands of 

 years without dividing islands, until they become at last mere clusters 

 of rocks, the last shreds of masses once continuous. To this state 

 many appear to have been reduced, and innumerable fantastic forms 

 are assumed by rocks adjoining the islands, to which the name 

 ' Drongs ' is applied, as it is to those of similar shape in Feive. The 

 granite rocks (fig. 48) between Papa Stour and Willswick Ness afford 

 an example ; a still more singular cluster of rocks is seen to the south 

 of Hillswick Ness (fig. 49), which presents a variety of forms as 

 viewed from different points, and has often been likened to a small 

 fleet of vessels with spread sails. Midway, between the groups of 

 Shetland and Orkneys, is Fair Island, said to be composed of sandstone, 

 with high perpendicular cliffs. The current runs with such velocity 

 that dui'ing a calm, when there is no swell, the rocks on its shores 

 are white with the foam of the sea driven against them. 



" The Orkneys, if carefully examined, would probably illustrate 

 our present topic as much as the Shetland group. The north-west 

 promontory of Sanda, one of these islands, has been cut off in modem 

 times by the sea, so that it became what is now called Start Island, 

 where a lighthouse was erected in 1807, since which the new strait 

 has grown wider." 



As regards the Orkneys, the following is taken fi'om the Ordnance 

 Ga%etteer of Scotland, under that head : — 



" Except in the Pentland Firth, where the depth of the sea reaches 

 40 fathoms, the water in the straits between the islands and their 

 immediate neighbourhood is nowhere deeper than 20 fathoms ; a rise 

 of 120 feet in the sea-bottom would unite the whole group, except 

 Sivona and the Pentland Skerries, into one mass of land, which would 

 be separated from the mainland of Scotland by a strait of from 2 to 3 

 miles broad, ^s^here the Pentland Firth is. If these sounds are, how- 

 ever, of moderate depth, their number and the broken and winding 

 outline of the coast are evidences of the hard struggle that constantly 

 takes place between the land and the Atlantic surge." 



" The intricate, indented coast-line, worn into creeks, and caves, and 

 overhanging cliffs — the crags, and Skerries, and sea stocks, once a part 



