On the Erratic Phenomena of Scandinavia. 237 



The presence of these arenaceous deposits, and the nature 

 of this sand, render the action of water evident ; for a moraine 

 of pure sand has never been observed, and no one has attri- 

 buted to glaciers the power of selecting the materials which 

 they transport, and of eliminating the felspar and mica while 

 they retain the quartz. 



The action of currents of water in the erratic phenomenon 

 of Scandinavia, therefore, appears to me to be incontestible ; 

 and it is only some points, to which I shall return at another 

 time, that can be the subject of discussion. Has the pheno- 

 menon been instantaneous, or has it lasted a certain time 1 

 Is it a simple or a complex phenomenon ? What is the cause 

 of the enormous force which has been in operation ? What 

 was its origin or point of departure 1 These are questions 

 which I shall not at present attempt to solve. 



II. — Remarks on the Observations of M, Durocher^ relative to the 

 Erratic Phenomena of Scandinavia. By Professor Agassiz. 



At the meeting of the Academy of Sciences of the 15tli De- 

 cember 1845, M. Elie de Beaumont communicated an extract 

 from a letter, sent to him by M. Agassiz, regarding M. 

 Durocher's observations relative to the erratic phenomena of 

 Scandinavia. Without entering into theoretical discussions, 

 and without arguing for the necessity of distinguishing be- 

 tween the phenomena produced by existing glaciers, and 

 those which may be attributed to the melting of the more 

 extensive glaciers of former times, or may be indirectly 

 connected with glaciers, M. Agassiz confines himself merely 

 to the indication of what seems to him to be inaccurate in 

 M. Durocher's manner of viewing the facts observed. *' It is 

 evident," says M. Agassiz, " to every one who endeavours to 

 distinguish the polishing effects of glaciers, from those due to 

 the action of water, that the undulating, sinuous, bifurcated, 

 and anastomosing, grooves and furrows mentioned by M. 

 Durocher are not mere grooves hollowed out by glaciers, but 

 are karren hollowed out by water, and scratched by the 

 glacier, similar to those of which we observe many examples 

 under the glaciers of Rosenlaui and Viesch, where these two 



