178 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 26, 



more and more round to the N. of E., and, what will probably sur- 

 prise him, as it certainly did me, he wiU see evidence that the agent 

 which impressed these furrows moved obliquely uphill, mounting a 

 slope of 700 or 800 feet ; he will then find himself on a sort of table- 

 land spotted with several small lakes, and along the rocky sides of 

 these reservoir-lakes he will observe some of the most beautiful ex- 

 amples of glaciation I have ever seen — long rectilinear grooves run- 

 ning uninterruptedly onwards from N.E. to S.W. for many yards, 

 with all lesser degrees of scratching and polish. Let him then 

 ascend over the ridges towards Cruach Lussa, and he will no longer 



Pig. 4. — Proille of the Ice-worn Knolls of Greenstone at the Crinan 



Canal. 



find these markings on their bare, weathered fronts ; but he wiU 

 notice the rounded snouts they present invariably to the N.E., and 

 the more rugged outlines to the S.W. Let him then continue aU 

 along until he gains the top of Cruach Lussa, the highest point in 

 North Knapdale (and 1530 feet above the sea, according to the 

 Admiralty chart), from whence, if the day be fine, he wiU have a 

 view. of one of the most beautiful scenes in Scotland, which alone 

 will recompense his toil if he be no geologist. 



§ 6. The ice, therefore, descending by Loch Eyne, seems to have 

 passed round and over this hUly ridge, just as the water of a river 

 flows round and over a large boulder in its bed. 



It seems odd to talk of a glacier doing this ; but nothing short of ice, 

 filling the valleys up to the brim, and covering the whole country in 

 one great winding-sheet, will meet the requirements of the case. In 

 short, we should have to describe it just in the way Eink speaks of 

 Greenland, when he tells us that a spectator standing on the top of 

 a mountain near the coast sees the various ice-streams " approach 

 and unite in an icy level occupying the whole of the eastern tract or 

 area of the continent," and which annually discharges its enormous 

 excess in those great icebergs that infest Bafiin's Bay and the neigh- 

 bouring seas. " To have a correct idea of the glacial accumulations 

 in Greenland," says that observant voyager. Dr. P. C. Sutherland, 

 " we must imagine a continent of ice flanked on its seaward side by a 

 number of islands, and in every other direction lost to vision in one 

 continuous and boundless plain. Through the spaces between these 

 apparent islands the enormous glacial accumulations slowly seek 

 their passage to the sea." In Melville Bay (lat. 75°), it presents to 

 the sea one continuous wall of ice, unbroken by land for a space of 

 70 or 80 miles; and the average thickness, he tells us, is 1200 

 to 1500 feet, but in some of the valleys upwards of 2400 feet 

 (Journ. of Geol. Soc. ix. p. 301). Somewhat similar, but much more 



