Valleys of the Bhine and Rhone. 159 



Rock Smoothings and Erratic Blocks. 



I willingly give my testimony to the striking character of 

 the smoothings observable on the rocky slopes by the way- 

 side, between Servoz and Les Ouches, in the valley of the 

 Arve. These are far below any present seat of permanent ice ; 

 but I think it is impossible to examine them without being 

 convinced that a glacier has at one time descended through 

 this part of the vale, and worn and polished the rocks in its 

 passage. 



The smoothing of the precipices at Montanvert, from one 

 to two hundred feet above the present bed of the Mer de 

 Glace, was pointed out in distinct terms by Professor Forbes, 

 who at the same time discovered traces at this place of the 

 ancient lateral moraine of that distinguished glacier. All of 

 these objects seem to me beyond question, and their connec- 

 tion with the barrier just alluded to is very interesting. 



There are smoothings, however, in certain situations, where 

 an ancient glacier, or an existing glacier in a larger volume 

 and more powerful action than at present, is not so readily 

 imagined. At the elevated col between the Arve valley and 

 the Val Orsine, smoothings are seen on both sides to a con- 

 siderable height. It has been thought that the Glacier 

 D'Argentiere had passed over this col ; but I am at a loss to 

 imagine its doing so in any circumstances. Even admitting 

 however, that such might have been the case, no such ex- 

 planation will account for precisely similar smoothings which 

 I observed on the face of the lofty Aiguilles Rouges, right 

 over this spot, a situation of great elevation, and entirely 

 unconnected with any imaginable glacier beds. 



In the valley of the Rhone, between Martigny and St 

 Maurice, the rock-faces near the bottom, on the side skirted 

 by the road, are in many places worn and smoothed, very 

 much after the manner of those near Servoz. There are 

 some good examples at Barme, where the hill advances a 

 good deal, so as to contract the valley. On the theory which 

 has been started, that a glacier once passed down the Rhone, 

 such appearances in such a situation are exactly what might 

 be expected. It is remarkable, however, that at the more 



