132 TRACES OF ANCIENT GLACIERS 



As already stated in my paper on Surface Geology, when I went among the 

 mountains of Wales, I had no recollection of the statements of the eminent geolo- 

 gists of Great Britain respecting its superficial deposits and markings: nor had I 

 then been in a country of glaciers. I soon recognized erosions on the sides and 

 bottoms of the valleys, quite similar to the drift markings with which I had been 

 familiar in New England. But I found several differences. In Wales the grooves 

 and striae followed the valleys, I thought almost exclusively, radiating from the 

 higher peaks of the Snowdonian range; nor did they reach to the top of the sides of 

 the valleys, but the mountains above were ragged, not embossed as in the United 

 States. I could not doubt that the erosions were produced by some force proceed- 

 ing from the central and elevated parts of the country, following down the valleys, 

 and in some spots I found that the slate rocks on the sides of the valley, had not 

 merely been smoothed and scored, but knocked over, as if by a heavy body 

 crowding against their upturned edges, and urging its way downwards. In short, 

 1 could not doubt that I had before me the marks of ancient glaciers. And I 

 stated my convictions on the subject before the British Association for the Ad- 

 vancement of Science, where I was happy to have them confirmed by Professor 

 Ramsay. That gentleman, I find, considers a glacier period to have preceded the 

 drift period in Wales, and a second period of glaciers to have followed. 



I make these statements to show how this subject has opened upon my mind. 

 And for the same reason I will subjoin some details of the facts that fell under my 

 observation in a sojourn of only a fortnight in Switzerland, respecting the former 

 °reater extent of its glaciers. The facts which I shall state can add nothing of 

 importance to the more important ones adduced by Agassiz, Guyot, and others, and 

 I suppose they have all been described. But I give them, both as a testimony in 

 favor of the views of those gentlemen, and because they prepare the way for facts 

 somewhat analogous, in New England. 



As I ascended Mount Righi from the side of Lake Zug, far above the ruins of 

 the famous Rossberg slide, certainly as high as the Stafflehaus, which, according to 

 my barometer, is 4854 feet above the ocean, we find strewed along the steep side 

 of the mountain, blocks of granite and gneiss, mixed with the Nagleflue, of which 

 the mountain is composed. These crystalline boulders must have come from the 

 higher parts of the Bernese Alps, and have constituted a lateral moraine. At least 

 I can in no other way explain their occurrence in such a situation. 



In ascending the Arve, from Geneva, we meet with remnants of former moraines 

 far below existing glaciers. Some four or five miles before reaching Chamouny, 

 we pass a defile, one or two miles long, where strias and roclies moutoiines are very 

 distinct ; the former conforming to the direction of the valley, and corresponding 

 exactly to the effects of existing glaciers. How could I doubt that they originated 

 in glaciers? If in North America I might strive to explain them by the action of 

 huo-e icebergs, yet how useless to talk of icebergs in a narrow and retired valley 

 of the Alps ? 



Most travellers who visit Chamouny ascend to the Flegere, on the northwest 

 side of the valley. Everywhere in the vicinity of the Chalet there, the rocks are 

 striated and rounded ; and as well as I could judge, the same is the case several 



