On the Erratic Phenomena of Scandinavia. 239 



edges of the glaciers of Rosenlaui, of the Aar, and of Viesch, 

 there are even cliffs which overhang to a great extent, and 

 whose under-surface, reposing on the glacier, is just as 

 much polished and scratched as the rocky bed on which the 

 glacier reposes ; and this can be easily understood, when we 

 know the manner in which glaciers follow all the sinuosities 

 of the valleys containing them, and mould themselves into all 

 their anfractuosities. It may not be unnecessary to remark 

 that, in this case, it is the fragments of rock lying at the sur- 

 face of the glaciers, and inserted between them and the flanks 

 of the valley, which act as the polishing emery. The finest 

 example that I have seen of an arch containing the margin 

 of a glacier, is situated below the great plateau of neve, which 

 extends from the Col of the Oberaar as far as the place 

 where the glacier of Viesch becomes enclosed in the valley 

 by which it issues. This arch is situated on the right mar- 

 gin of the glacier, near a small lake at the foot of the Aeg- 

 gishorn. Another similar arch is to be seen near the ex- 

 tremity of the glacier of Rosenlaui, on its right flank ; and 

 I can cite a third on the left flank of the glacier of the Aar, 

 at the foot of the peak of the Rothorn de I'Aar. 



" These facts evidently prove, that the arguments of M. 

 Durocher against the action of glaciers have no foundation 

 in truth ; because we observe in a multitude of localities, the 

 phenomena which he considers as incompatible with the ac- 

 tion of glaciers, produced by existing glaciers themselves. 



" Moreover, I have never asserted that the action of water 

 had nothing to do with glacial phenomena ; but, on the con- 

 trary, I have always endeavoured to distinguish the share 

 due to the glacier properly so called, from that which must 

 be attributed to the effects of the melting of glaciers, and to 

 the torrents which were the result ; and I have cited vari- 

 ous examples of gravel which has been stratified by water 

 hemmed in on the edges of glaciers, or issuing from their 

 extremities. I maintain, from the study of the facts which 

 I have observed and compared, that glaciers have formerly 

 been of immense extent, — an extent which we shall be the 

 better enabled to determine in proportion as we learn to 

 distinguish with more precision the phenomena caused by 



