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ancient seacliff, a short distance N. of the White Water. It is a true 

 boulder, granite reposing upon sandstone. We estimated the weight 

 at more than 2,000 tons. What force could have hurled a mass so 

 enormous from the mountain-side ? Not gravity urging its descent ; 

 unless, perhaps, the first impulse was given by an earthquake, for 

 the slope of the hill-side is gradual, and the mass itself ill adapted 

 for easy rolling. But if we admit the agency of ice, we have a 

 force adequate to the transport. This transport took place before 

 the present level of land and water was established ; the cliff was 

 not yet cut out from the sloping hill-side ; the bed on which the 

 boulder now reposes was the sea bottom, and in the glacial period it 

 may have glided down upon icy sheets descending from the corries, 

 or been borne off by a berg which deposited here the heaviest portion 

 of its load. A sister block rests upon the same cliff, on the south side 

 of the burn; but its dimensions are much less. The shore is 

 strewed with multitudes of similar masses of all sizes. 



84. In passing along the road towards Brodick, we are upon sand- 

 stones of the carboniferous system, dipping south at small angles, but 

 often disturbed by the numerous dikes which cross the strata in 

 various directions. On our right is the picturesque cliff, the old sea- 

 margin, hollowed into caves, and bearing other marks of the former 

 action of the waves. From these caves, from the summit of the 

 cliffs, and from the low terrace along which the road is carried, once 

 the sea bottom, many marine shells have been obtained. The great 

 proportion are the same as those now inhabiting the shores of the 

 Clyde; but with them are associated a few of those arctic species 

 which we have already given (Art. 7), in the list kindly furnished by 

 Mr. Smith, of Jordanhill; thus indicating the prevalence of the same 

 conditions which obtained during the era of the boulder clay. 



Between Brodick pier and the fine picturesque group of ash 

 trees near the beach, there are some remarkable dikes which disturb 

 the stratification of the sandstone, and are obviously connected here, 

 as at the other extremity of the beach (Art. 70), with the appear- 

 ance of the rock from beneath the sands. The ridge of gravel and 

 sand dividing the beach from the marsh behind is the joint work of 

 the sea and the two streams. The Cloy burn formerly entered the 

 bay at Invercloy, as the name of the village implies ; the course was 

 changed by a bar cast up in a storm, and it has now for a long 

 period followed the winding course which unites it with the Rosa 

 burn before reaching the sea. 



