NORTH AND WEST COASTS. 27 



lowed out into deep caverns, or fashioned into 

 arches and pinnacles, and innumerable grotesque 

 forms, presenting altogether a scene of extraordi- 

 nary grandeur even in calm weather ; but during 

 a storm, when the tremendous billows roll in from 

 the westward, exhibiting a degree of sublimity 

 which it is scarcely possible to conceive. 



The vast extent of the western coasts of Scotland 

 renders anything beyond a general description 

 wholly impossible within the limits of this sketch. 

 From Cape Wrath southwards to the great estuary 

 of the Clyde, the coast, with its numerous indenta- 

 tions forming bays and gulfs, or " lochs," which 

 reach far into the land, exhibits a great variety of 

 romantic scenery. The geological formations con- 

 sist for the most part of rocks of granite, gneiss, 

 trap, porphyry, quartz, and in a few instances of 

 stratified rocks, such as the old red sandstone and 

 clay slate, the former occurring on the shores of 

 Ross-shire, the latter on those of Argyle. On the 

 southern shores of the Firth of Clyde the character 

 of the coast becomes entirely different from that 

 which prevails on the northern or the north-wes- 

 tern shores. The aspect is comparatively uniform, 

 with little of the wild and romantic appearance 

 peculiar to the plutonic and metamorphic forma- 

 tions. From about Greenock, conglomerates, and 

 old red sandstone strata reach to Ardrossan, to the 

 south of which place the coal formation occurs, 

 bounded beyond Ayr by the red sandstone. 

 Southwards from Grirvan the rocks of the Silurian 

 system occur, and the northern shores of the Sol- 



