1908-1909.] on the Scenery of Scot Ian d* 1 09 



For millions of years the elements, which in a few genera- 

 tions fret the straight edge of a castle wall, have been eating 

 into the ancient volcanoes, until their early shape has dis- 

 appeared. We must remember, too, that through gradual 

 changes of level the land has been frequently overwhelmed 

 by the ocean, which has done its share in obliterating the 

 traces of volcanic action, by actually sweeping some away, by 

 covering more with fresh deposits worn from pre-existing land 

 surfaces. Last in the process of effacement came the great 

 ice sheets of the glacial period, which with their enormous 

 weight — for some were thousands of feet thick — partially 

 erased the obstructions that stood in their path as they 

 ground their steady way to the sea. Because of these things 

 we may not now see Scottish volcanoes as they originally 

 existed. At best we can only guess at their magnitude from 

 the mere shadows (magnificent relics, nevertheless) which 

 have escaped the ravages of weather and sea and glacier. 



The traces of volcanic dihris which occur in places, associated 

 with the unrecognisably old, crumpled rocks of north-east 

 Scotland, are negligible from a scenic point of view. Almost 

 negligible, too, are the sheets of ashes which lie between 

 sea-deposits of Ordovician age, notwithstanding that they are 

 estimated to cover an area of some 2000 square miles; for it 

 is only here and there, in Ayrshire and in Mthsdale, that they 

 become visible, borne to the surface on the crests of great 

 rock-folds. 



Indeed, not until the period known as the " Old Eed 

 Sandstone" Age do we find noteworthy records of erup- 

 tions. It is surmised that where Scotland now exists, several 

 great lakes had come into being, stocked with myriads of 

 strange fishes and living stone-lilies, bordered by groves of 

 " horse-tail "-like trees. This was an age of intense volcanic 

 activity. Groups of volcanoes arose which, discharging lava 

 streams and showers of ashes, built up mountains of such 

 magnitude that in the neighbourhood of Stirling they are 

 estimated to have reached a height of 6500 feet. To this 

 period we owe some of the rugged scenery near the Pass of 

 Glencoe, and of the hills which lie westwards of Loch Awe. 

 Still more important are the ranges of the Ochil and Sidlaw 

 Hills — together some fifty miles long — formed of lava and 



