1867.] Ice Marks in North Wales. 45 



there are no signs of ancient glaciers, or no reason to believe that 

 the country has in recent geological times been subjected to the 

 action of ice, these lakes are either very few, or (much more 

 frequently) entirely absent. So vast is the disproportion, that if 

 we leave out such lakes as are near the sea-coast, or in alluvial 

 plains where they may have been easily formed by changes in the 

 course of rivers, and such as in volcanic countries are formed in 

 the craters of old volcanos, it is probable that for every thousand 

 lakes that exist in glaciated districts, not one can be counted in all 

 the rest of the globe ! There is, therefore, a strong prima facie 

 case in favour of a theory which directly connects glaciers and lakes 

 as cause and effect ; and the opponents of that theory, if they cannot 

 absolutely prove it to be false in a good many cases, should be 

 prepared with some plausible hypothesis which will equally well 

 explain this prominent fact. Yet, strange to say, I have been 

 unable to find that any such hypothesis has been yet put forth. 

 Professor Ramsay's opponents all confine themselves to pointing 

 out the difficulties of his theory in particular cases. They say that 

 ice cannot travel up a long slope from a depth of more than 2,000 

 feet ; that it would remain immovable at such depths, the upper 

 layers sliding over the lower ; that a glacier's power of erosion is 

 very slight ; that the ends of some existing glaciers are seen to 

 rest on loose moraine matter without even disturbing it; and 

 other arguments of a similar nature.* These arguments may be 

 good or bad, and Professor Eamsay has answered them all himself 



* It appears to have escaped the notice, "both of Professor Eamsay and of his 

 opponents, that in the paper which immediatey precedes that on the " Glacial 

 Origin of Lakes" in the Geological Society's Journal of Angust 1st, 1862, Mr. 

 Jamieson adduces evidence of the very fact which has so repeatedly heen denied 

 in reference to Professor Kamsay's theory, namely, that a glacier can move bodily 

 for a considerable distance up a slope. Mr. Jamieson states, that from the point 

 where the gorge "below Loch Trieg opens into Glen Spean, all the ice-marks 

 indicate that the glacier had parted in two directions, flowing both down the 

 valley to the west, and up the valley to the east, along Loch Laggan and over the 

 pass of Makoul into the valley of the Spey. This is proved hy the lower side of 

 the rocks being abraded and smoothed above the entrance to Loch Treig, while 

 lower down it is the upper sides that are ice-worn. In Glen Eoy also the same 

 thing has occurred, the glacier having moved up it instead of down it, and dis- 

 charged itself over the water-shed into another valley instead of by what now 

 appears its natural outlet into Glen Spean. A sufficient cause for this extra- 

 ordinary phenomenon seems to be found in the former immense accumulation of 

 ice in Glen Spean, rising far up above both these low passes, as proved by plain 

 ice-marks to the height of more than 2,000 feet. It would be very important to 

 have an accurate survey made of this district, with all the heights well determined, 

 .and a thorough examination of the glacial phenomena it presents. These, as 

 described by Mr. Jamieson, clearly indicate that in two separate cases glaciers 

 about twelve miles long have been forced to move up hill, and to empty them- 

 selves over the passes at the heads of their respective valleys ; and that in so doing 

 they have abraded the rocks at the sides and bottoms of the valleys, showing that 

 the ice could not have remained stationary below while it was flowing on above. 



