64 



very grand, especially when they are seen in the early summer 

 twilight, their dark jagged peaks projected against a background of 

 sky, still lit up with brilliant hues from the departed sun. Their 

 aspect from one such point of view has been given with noble effect 

 by a living artist. The terrace border, so conspicuous around the 

 estuary of the Clyde, is marked here with less continuity, owing to 

 the nature of the rocks which advance in many parts upon the sea 

 line in mural precipices. Still, however, it is sufficiently distinct in 

 many parts, as about Corriegills, Whiting bay, portions of the south 

 End, and towards King's Cove on the west, where its salient and 

 re-entrant angles, in their bold points and noble sweeps, afford some 

 of the finest scenes of quiet beauty to be met with in Scotland. 



General Outline of the Structure. 



44. The remarkable geological structure of Arran, and the strik- 

 ing physical features which give such a charm to its scenery, are 

 alike due to a single peculiarity generally overlooked by those who 

 undertake to describe it. This consists in the abnormal position of 

 its granite nucleus. The other granite tracts of the north-west of 

 Scotland lie amid primary slates, which are symmetrically disposed 

 on opposite sides of it, the granite ridge forming an anticlinal axis. 

 This is the case throughout the Grampians, where gneiss and mica 

 slate widely encircle the various outbursts of the granitic rocks ; the 

 silurian slates of the south of Scotland envelop in the same manner 

 the granitic bosses which rise amid them. But in Arran there is no 

 such symmetrical arrangement ; granite does not form a mineral axis 

 in reference to the slate rocks. It has been protruded close to the outer 

 border of the two upper slates, so as to come into contact on one 

 side with the newer sedimentary strata. Its position is thus very 

 different from that of the Grampian granite, being far removed from 

 the axis of the old crystalline slates, and associating it with sedimen- 

 tary strata of a much later age. The newest of the two upper slates 

 noticed in Art. 30 is not found in Arran, and is probably either 

 thrown out westward beyond the line of bearing of the second slate, 

 or is so altered by the near proximity of the granite as to be undis- 

 tinguishable from the middle or dark coloured slate, through whicli 

 the granite has been protruded. On the east side of the granite 

 nucleus about Corrie, this slate band is extremely narrow, probably 

 only a few yards thick in many places ; on the western side it is 

 much broader, but the underlying mica slate does not appear, and is 

 not found till we pass into the opposite peninsula of Cantire, where 

 we meet with it on arriving at the line of bearing which it preserves, 



