58 TOWN GEOLOGY. [lu 



rock, in the direction in which a glacier would have 

 pressed against it had one been there. Where these 

 polishings and scorings are found in narrow glens, it 

 is, no doubt, an open question whether some of them 

 may not be the work of water. But nothing but the 

 action of ice can have produced what I have seen in 

 land-locked and quiet fiords in Kerry ice-fluting sin 

 polished rocks below high-water mark, so large that 

 I could lie down in one of them. Nothing but the 

 action of ice could produce what may be seen in any 

 of our mountains whole sheets of rock ground down 

 into rounded flats, irrespective of the lie of the beds, 

 not in valleys, but on the brows and summits of 

 mountains, often ending abruptly at the edge of some 

 sudden cliff, where the true work of water, in the 

 shape of rain and frost, is actually destroying the 

 previous work of ice, and fulfilling the rule laid down 

 (I think by Professor Geikie in his delightful book on 

 Scotch scenery as influenced by its geology), that ice 

 planes down into flats, while water saws out into crags 

 and gullies ; and that the rain and frost are even now 

 restoring Scotch scenery to something of that rugged- 

 ness and picturesqueiiess which it must have lost when 

 it lay, like Greenland, under the indiscriminating 

 grinding of a heavy sheet of ice. 



Lastly ; no known agent, save ice, will explain 

 those perched boulders, composed of ancient hard 

 rocks, which may be seen in so many parts of these 

 islands and of the Continent. No water power could 

 have lifted those stones, and tossed them up high 

 and dry on mountain ridges and promontories, upon 

 rocks of a totally different kind. Some of my readers 

 surely recollect Wordsworth's noble lines about these 



