29O WORK ON 'MAN.' [1869. 



editions do not mean real success. The book has sold ; the 

 guess has been talked over ; and the circulation and discus- 

 sion sum up the significance of the editions." Mr. Robert- 

 son makes the true, but misleading statement : " Mr. Darwin 

 prefaces his fifth English edition with an Essay, which he 

 calls ' An Historical Sketch,' &c." As a matter of fact the 

 Sketch appeared in the third edition in 1861. 



Mr. Robertson goes on to say that the Sketch ought to 

 be called a collection of extracts anticipatory or corroborative 

 of the hypothesis of Natural Selection. " For no account is 

 given of any hostile opinions. The fact is very significant. 

 This historical sketch thus resembles the histories of the 

 reign of Louis XVIII., published after the Restoration, from 

 which the Republic and the Empire, Robespierre and Buo- 

 naparte were omitted." 



The following letter to Prof. Victor Carus gives an idea 

 of the character of the new edition of the ' Origin : '] 



C. Darwin to Victor Carus. 



Down, May 4, 1869. 



... I have gone very carefully through the whole, trying 

 to make some parts clearer, and adding a few discussions and 

 facts of some importance. The new edition is only two 

 pages at the end longer than the old ; though in one part 

 nine pages in advance, for I have condensed several parts 

 and omitted some passages. The translation I fear will cause 

 you a great deal of trouble ; the alterations took me six weeks, 

 besides correcting the press ; you ought to make a special 

 agreement with M. Koch [the publisher]. Many of the cor- 

 rections are only a few words, but they have been made from 

 the evidence on various points appearing to have become a 

 little stronger or weaker. 



Thus I have been led to place somewhat more value on 

 the definite and direct action of external conditions ; to think 

 the lapse of time, as measured by years, not quite so great as 

 most geologists have thought ; and to infer that single varia- 



