338 ARRAN. ALLUVIA. 



is a gradual transition from the solid rock to the loose 

 clay ; the fragments of the former diminishing in size 

 and number till they vanish in the mass of rubbish and 

 red earth. Where the sandstone strata are more solid, 

 and reach the surface, they also present the same ten- 

 dency to gradual decomposition, being covered with 

 thinner and more partial deposits of the same alluvial 

 matter. It is easy therefore to perceive in Cantyre that 

 which is less obvious in Arran ; that the alluvia in ques- 

 tion are untransported materials formed in their present 

 places by the destruction of subjacent beds of sandstone ; 

 and thus the alluvial tract of Coryravie admits of an 

 easy explanation. 



Alluvial deposits, of small extent, but of similar charac- 

 ters, are found in other parts of the island ; but it is 

 unnecessary to describe them, since they offer no par- 

 ticular interest either in a topographical or scientific 

 view. 



Besides these alluvia, of general occurrence every 

 where, Arran displays alluvial deposits of somewhat dis- 

 tinct characters. The first of these, although common 

 on many of our shores, is so^rare in the islands described 

 in this work, as to render it an object worthy of notice. 

 This consists of a bed of pebbles skirting the greater 

 part of the coasts, often to a considerable extent, and 

 having by a gradual accumulation, repelled the sea from the 

 solid materials of the island, which have once apparently 

 been washed by it. It is very remarkable between Loch 

 Ransa and the mouth of the lorsa, as also from Loch 

 Ransa to Lamlash bay ; throughout the greater part of 

 which extensive tracts, it is covered with grass and 

 converted to the purposes of pasturage and agriculture. 

 It occurs also conspicuously on the southern shore, and, 

 with few exceptions, may indeed be considered as forming 

 a belt round the island. Independently of its agricultural 

 value, it furnishes a level road of communication throughout 

 the greater part of the country, and is the more striking, 



