130 GEOLOGY OF ARRAN. 



flat beach, about two feet wide. They terminate in the 

 sandstone, almost opposite to one another, and are prolonged 

 in contrary directions. 



62. The Scriden is a headland whose base is strewed with 

 immense masses of sandstone. These fell about 100 years 

 ago with a loud noise, heard in Bute and Argyll. The 

 debacle is more extensive than that of the Fallen Rocks, 

 but inferior in grandeur. It was produced by a landslip of 

 the mountain side, the traces of which yet remain in a long 

 deep rent near the summit. Scrambling for a long way 

 among the fallen masses, we reach an open shingly beach, 

 along which the line of the old slate, advancing from the 

 interior, strikes the shore, and cuts off the red sandstone; 

 but the nature of the ground does not permit the junction to 

 be seen. The slate here dips about S.E. at 40. The change 

 takes place near a glen, with a burn called Alt-Mhor (large 

 burn). The variety called chlorite shite occurs here, and 

 quartz abounds in veins and beds in the slate. 



A short distance forward, at Newton Point, where the 

 coast bends round into Loch Ranza, and a small stream, 

 called Alt-Beith (birch burn), enters the sea, there occurs 

 one of the most instructive sections to be seen in Arran. 

 Strata of sandstone again occupy the shore for 300 yards, 

 dipping into the sea, and resting along the platform in front 

 of the cliffs upon the upturned edges of the strata of slate. 

 These make an angle of 40 with the horizon, and dip 40 E. 

 of S., that is towards the granite of the nucleus ; the strata 

 of sandstone are inclined at 25 and dip 55 W. of N. ; the 

 dips being thus nearly in opposite directions (see Art. 5, 

 sub fin). This uneouformability indicates that the slate, 

 itself a sedimentary deposit, had not only been formed in this 

 regular stratitication, but had undergone a general disturb- 

 ance before the sandstone beds were thrown down upon it. 

 The position of the slate-strata is thus not directly related to 

 the granite; the dip and strike are really related to the 

 great axis of elevation traversing the mainland towards the 



