1841 — 1882] ICE-Ai TIO 153 



been produced by a glacier, owing to the dryness of the lateral Letter 501 

 valley and general infrequency of glaciers in Himalaya ; but 

 pray observe that we may fairly 1 from what we see in Europe) 



assume that the climate was formerly colder in India, and 

 when the land stood at a lower height more snow might have 

 fallen. Oddly enough, 1 am now inclined to believe that 

 I saw a gigantic moraine crossing a valley, and formerly 

 causing a lake above it in one of the great valleys (Valle 

 del Ycso) of the Cordillera : it is a mountain of detritus, 

 which has always puzzled me. If you have any further 

 opportunities, do look for scores on steep faces of rock ; and 

 here and there remove turf or matted parts to have a look. 

 Again I beg, do not give up Geology : — I wish you had 

 Agassiz's work ' and plates on Glaciers. I am extremely sorry 

 that the Rajah, ill luck to him, has prevented your crossing to 

 Thibet ; but you seem to have seen most interesting 

 country : one is astonished to hear of Fuegian climate in 

 India. I heard from the 'Sabines that you were thinking of 

 giving up Borneo ; I hope that this report may prove true. 



To C. Lycll. Letter 502 



Down, May 8th [1855]. 



The notion you refer to was published in the Geological 

 Journal: Vol. 1 Y. (1848), p. 315, with reference to all the cases 

 which I could collect of boulders apparently higher than the 

 parent rock. 



The argument of probable proportion of rock dropped by 

 sea ice compared to land glaciers is new to me. I have often 

 thought of the idea of the viscosity and enormous momentum 

 of great icebergs, and still think that the notion I pointed out 

 in appendix 3 to Ramsay's paper is probable, and can hardly 

 help being applicable in some cases. I wonder whether the 

 Phil. Journal [Magazine?] ' would publish it. if I could get 



1 Etudes sur les Glaciers. L. Agassiz, Neuchatel, 1840. 



1 " On the TransportaJ of Erratic Boulders from a lower to a higher 

 Level." By C. Darwin. 



:! The paper by Ramsay has no appendix ; probably, therefore, 

 Mr. Darwin's notes were published separately as a paper in the Phil. 

 Mag. 



4 " On the Power of Icebergs to make rectilinear, uniformly-directed 

 grooves across a Submarine Undulatory Surfa By C. Darwin, Phil, 



Mag., Vol. X., p. 96, 1855. 



