Alfred Russel Wallace 



is new, and I shall be anxious to hear if it at all helps to 

 get over your difficulties. 



I have been lately revising and adding to my various 

 papers bearing on the ^^ Origin of Species," etc., and am 

 going to print them in a volume immediately, under the 

 title of ^^ Contributions to the Theory of Natural Selec- 

 tion : A Series of Essays." 



In the last, I put forth my heterodox opinions as to 

 Man, and even venture to attack the Huxleyan philo- 

 sophy ! 



Hoping you are quite well and are getting on with your 

 Man book, believe me, dear Darwin, yours very faithfully, 



Alfred E. Wallace. 



P.S. — When you have read the proof and done with it, 

 may I beg you to return it to me ? — A. B. W. 



Down, Beckenham, Kent^ S.E. January 26, [1870]. 



My dear Wallace, — I have been very much struck by 

 your whole article (returned by this post), especially as to 

 rate of denudation, for the still glaciated surfaces have of 

 late most perplexed me. Also especially on the lesser muta- 

 tions of climate during the last 60,000 years; for I quite 

 think with you no cause so powerful in inducing specific 

 changes, through the consequent migrations. Your argu- 

 ment would be somewhat strengthened about organic 

 changes having been formerly more rapid, if Sir W. 

 Thomson is correct that physical changes were formerly 

 more violent and abrupt. 



The whole subject is so new and vast that I suppose 

 you hardly expect anyone to be at once convinced, but 

 that he should keep your view before his mind and let it 

 ferment. This, I think, everyone will be forced to do. I 

 have not as yet been able to digest the fundamental notion 



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