LYELL. 337 



proportionate length of the periods compared." He 

 noticed an old terminal moraine, in advance of the 

 nevv one of the Rhone glacier, covered with wild 

 p'.ants, some in full flower, and cut through in two 

 places by the river ; its height was only fifteen feet, 

 and its width ninety feet. He went underneath the 

 Viesch glacier in the Upper Vallais, and beyond it ; 

 in consequence of its having melted much, he saw 

 a rounded and domed surface of granite, smooth, 

 and with straight furrows a quarter of an inch deep 

 exactly in the direction of the onward movement 

 of the glacier. On the Ruffelhorn, on the right 

 lateral moraine, that is on the surface of the ice 

 close to the rocks, he saw a splendid mass of granite, 

 angular in shape, and measuring fifty-nine feet long, 

 forty-nine feet wide, and forty-two feet high. Its 

 sides were polished and furrowed. This huge mass 

 was being carried slowly down, by the glacier, and 

 will be deposited at its foot some day or other. 

 Once it formed a part of the valley side, and it 

 fell on to the glacier, whose flanks had scrubbed it for 

 many a long day. He particularly noticed how 

 the glaciers had been advancing of late years (just 

 as they are now receding). 



Lyell followed out these researches on the south 

 of the Alps, and he first of all made many excursions, 

 accompanied by Gastaldi, one of the best of the 

 scientific men of Turin, and by Michelotti, in order 

 to compare the shells which are found fossil in the 

 middle tertiary strata on the south of the Alps, with 

 those of the molasse of Switzerland to the north. He 



I. z 



