214 



Natural Terraces on the Eildon Hills, 



would be ground against each other by every tide, into 

 smooth pebbles and shingle. Nor is it easy to conceive how 

 terraces of 100 or 120 yards broad, as on the Eildons, formed 

 of angular stones detached and precipitated from above, could 

 have been made to assume by the action of water, even the 

 irregular horizontality they do actually possess, when falling 

 upon a slope having an angle of thirty or forty degrees ; and 

 this, without the stones showing any marks of attrition. On 

 a gently inclined beach, where the tidal wave is ever and 

 anon rolling such fragments over a considerable area, they 

 would soon be converted into rounded pebbles; but on a 

 steep rocky shore they would fall at once into deep water and 

 assume the shape of a conical talus or ei scree," where the 

 tide would have comparatively little effect upon them. Their 

 rough angular surfaces would lock into each other, and pre- 

 vent them from being scattered over so broad a space as we 

 see them on the Middle Eildon. It must also be borne in 

 mind, in reference to the terraces on the eastern hill, which 

 appear to have slipped down from their original situation, that 

 the probability of their having done so is much weakened by 

 their being composed of angular stones. 



It struck me as singular, that all the terraces I examined, 

 should be found on the sides of the respective hills most ex- 

 posed to the strong currents that may be assumed to have 

 been then in action ; those on the north side of the Eildons, 

 facing the great valley of the Tweed; those on William- 

 law, overhanging the more circuitous one of Gala water. Of 

 course I conclude they do exist on the retired sides of some 

 of the hills. One should have supposed, a priori, that the 

 currents would have swept away the fragments of rock as 

 they fell from above, and would have prevented them from 

 accumulating into projecting shelves. Indeed, several of the 

 best developed are widest precisely at the point where they 

 project into the valley, and would come in contact with the 

 current. I was also surprised to find no trace of terraces in 

 other situations, apparently more favourable to their produc- 

 tion. Immediately to the west of Williamlaw, and seen to 

 advantage from its summit, is a wide and deep circular am- 

 phitheatre, formed by the smooth grassy sides of several 

 neighbouring hills which environ it with very uniform slopes, 

 except on the side that connects it with the valley of the Gala 

 water. If the sea ever occupied the latter, it must also have 

 filled this hollow, and converted it into a spacious, though 

 sheltered and tranquil bay, round whose encircling sides, well- 

 developed terraces might be expected to be found. Their 

 total absence, therefore, from so favourable a locality, leaves 

 room to inquire whether those which occur in more equi- 



