1859J RESTING AT ILKLEY. 527 



Can you tell me of any good and speculative foreigners to 

 whom it would be worth while to send copies of my book, on 

 the ' Origin of Species ' ? I doubt whether it is worth sending 

 to Siebold. I should like to send a few copies about, but 

 how many I can afford I know not yet till I hear what price 

 Murray affixes. 



I need not say that I will send, of course, one to you, in 

 the first week of November. I hope to send copies abroad 

 immediately. I shall be ifitensely curious to hear what effect 

 the book produces on you. I know that there will be much 

 in it which you ^yill object to, and I do not doubt many errors. 

 I am very far from expecting to convert you to many of my 

 heresies ; but if, on the whole, you and two or three others 

 think I am on the right road, I shall not care what the mob 

 of naturalists think. The penultimate chapter,* though I 

 believe it includes the truth, will, I much fear, make you 

 savage. Do not act and say, like Macleay versus Fleming, 

 >"I write with aqua fortis to bite into brass." 



Ever yours, 



C. Darwin. 



C. Darwin to C. Lyell. 



Ilkley, Yorkshire, 



Oct. 20th [1859]. 



My dear Lyelt-, — I have been reading over all your let- 

 ters consecutively, and I do not feel that I have thanked you 

 half enough for the extreme pleasure which they have given 

 me, and for their utility. I see in them evidence of fluctua- 

 tion in the degree of credence you give to the theory ; nor 

 am I at all surprised at this, for many and many fluctuations 

 I have undergone. 



There is one point in your letter which I did not notice, 

 about the animals (and many plants) naturalised in Australia, 

 which you think could not endure without man's aid. I can- 

 not see how man does aid the feral cattle. But, letting that 



* Chapter XIII. is on Classification, Morphology, Embryology, and 

 Rudimentary Organs. 



