18411882] ICE-ACTION 149 



confession that ordinary glaciers could not have transported Letter 499 

 the blocks there, and if an hypothesis is to be introduced 

 the sea is much simpler ; floating ice seems to me to account 

 for everything as well as, and sometimes better than the 

 solid glaciers. The hollows, however, formed by the ice- 

 cascades appear to me the strongest hostile fact, though 

 certainly, as you said, one sees hollow round cavities on 

 present rock-beaches. 



I am glad to observe that Agassiz does not pretend that 

 direction of scratches is hostile to floating ice. By the way, 

 how do you and Buckland account for the " tails " of diluvium 

 in Scotland ? l I thought in my appendix this made out 

 the strongest argument for rocks having been scratched by 

 floating ice. 



c_? 



Some facts about boulders in Chiloe will, I think, in a 

 very small degree elucidate some parts of Jura case. What 

 a grand new feature all this ice work is in Geology ! How 

 old Hutton would have stared ! 2 



I ought to be ashamed of myself for scribbling on so. 

 Talking of shame, I have sent a copy of my Journal with 

 very humble note to Agassiz, as an apology for the tone I 

 used, though I say, I daresay he has never seen my appendix, 

 or would care at all about it. 



I did not suppose my note about Glen Roy could have 

 been of any use to you I merely scribbled what came 

 uppermost. I made one great oversight, as you would 

 perceive. I forgot the Glacier theory : if a glacier most 

 gradually disappeared from mouth of Spean Valley [this] 

 would account for buttresses of shingle below lowest shelf. 

 The difficulty I put about the ice-barrier of the middle Glen 



1 Mr. Darwin speaks of the tails of diluvium in Scotland extending 

 from the protected side of a hill, of which the opposite side, facing the 

 direction from which the ice came, is marked by grooves and strise (loc. 

 tit., pp. 622, 623). 



2 James Hutton (1726-97), the author of a Theory of the Earth. Sir 

 Charles Lyell speaks of the Huttonian theory as being characterised 

 by " the exclusion of all causes not supposed to belong to the present 

 order of Nature" (Lyell's Principles, ed. XII., vol. I., p. 76, 1875). Sir 

 Archibald Geikie has recently edited the third volume of Hutton's Theory 

 of the Earth, printed by the Geological Society, 1899. See also The 

 Founders of Geology, by Sir Archibald Geikie ; London, 1897. 



3 Journal and Remarks, 1832-36. See note 2, p. 148. 



