I859-] RESTING AT TLKLEY. 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 intensely curious to hear what effect 

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

 in it which you will 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 LYELL, 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. 



