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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, striken 

 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 slate 

 occurs here, and quartz abounds in veins and beds in the slate. 



91. 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 instruc- 

 tive 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. TKese make an angle of 40 with the horizon, and dip 40 

 E. of S,; the strata of sandstone are inclined at 25 and dip 55 W. 

 of N. ; the dips being thus nearly in opposite directions (see Art. 

 45, sub Jin.) This unconformability indicates that the slate, itself 

 a sedimentary deposit, had not only been formed in this regular stra- 

 tification, but had undergone a general disturbance, before the sand- 

 stone beds were thrown down upon it. The position of the slate- 

 strata has no relation to the granite of the nucleus; the dip and 

 strike are related to the great axis of elevation traversing the country 

 in the direction of the Grampian chain. This position had been 

 acquired before the Arran granite was injected amid the strata of 

 slate, and ere yet any of the sandstone beds which succeed it had 

 been deposited. These sandstones (old red and carboniferous) are 

 conformable to one another, and the deposits blend, at both sides of 

 the section, Achab farm and the Fallen Rocks-. But we see here, 

 as repeatedly noticed already, that neither deposit has any relation 

 to the stratification of the slate, which had sustained extensive dislo- 

 cation before the deposit of the old red sandstone had begun. The 

 cut annexed represents the appearances at this place. 



The sandstone strata here alternate with beds of limestone and con- 

 glomerate. The lowest bed, b, next the slate, a, is a hard crystalline 

 white limestone, about six feet thick ; it contains quartz pebbles, 

 schist, and diffused siliceous matter ; and is without fossils. There 

 are several beds higher in the series, but the thickness is less. 



