i8 4 3— 1882] GLACIAL ACTION 471 



get hardly any except the Caltha, and if ever I stumble on Letter 358 

 that plant in seed I will try it. 



I wish to Heaven some one would examine the rocks 

 near sea-level at the south point of Greenland, and see if 

 they are well scored ; that would tell something. But then 

 subsidence might have brought down higher rocks to present 

 sea-level. I am much more willing to admit your Nonvego- 

 Greenland connecting land than most other cases, from the 

 nature of the rocks in Spitzbergen and Bear Island. You 

 have broached and thrown a lot of light on a splendid 

 problem, which some day will be solved. It rejoices me to 

 think that, when a boy, I was shown an erratic boulder in 

 Shrewsbury, and was told by a clever old gentleman that 

 till the world's end no one would ever guess how it came 

 there. 



It makes me laugh to think of Dr. Dawson's indignation 

 at your sentence about "obliquity of vision." 1 By Jove, he 

 will try and pitch into you some day. Good night for the 

 present. 



To return for a moment to the Glacial period. You 

 might have asked Dawson whether ibex, marmot, etc., etc., 

 were carried from mountain to mountain in Europe on float- 

 ing ice ; and whether musk ox got to England on icebergs ? 

 Yet England has subsided, if we trust to the good evidence 

 of shells alone, more during Glacial period than America 

 is known to have done. 



For Heaven's sake instil a word of caution into Tyn- 

 dall's ears. I saw an extract that valleys of Switzerland 

 were wholly due to glaciers. He cannot have reflected on 

 valleys in tropical countries. The grandest valleys I ever 

 saw were in Tahiti. Again, if I understand, he supposes 

 that glaciers wear down whole mountain ranges ; thus lower 

 their height, decrease the temperature, and decrease the 

 glaciers themselves. Does he suppose the whole of Scotland 

 thus worn down? Surely he must forget oscillation of level 

 would be more potent one way or another during such 

 enormous lapses of time. It would be hard to believe any 

 mountain range has been so long stationary. 



I suppose Lycll's book 2 will soon be out. I was very 



1 See Letter 144. 



'' The Antiquity of Man, 1863. 



