LETTERS OF CHARLES DARWIN. 401 



spondent here; but I must think you are too hopeful on your side of 

 the water. I never believed the 'canards' of the army of the Potomac 

 having capitulated. My good dear wife and self are come to wish for 

 peace at any price. Good night, my good friend. I will scribble on 

 no more. 



One more word. I should like to hear what you think about what 

 I say in the last chapter of the orchid book on the meaning and cause 

 of the endless diversity of means for the same general purpose. It 

 bears on design, that endless question. Good night, good night ! 



To J. D. Dana. 



Down, Dec. 5th, 1849. 



I have not for some years been so much pleased as I have just been 

 by reading your most able discussion on coral reefs. I thank you most 

 sincerely for the very honourable mention you make of me. This day 

 I heard that the atlas has arrived, and this completes your munificent 

 present to me. I have not yet come to the chapter on subsidence, and 

 in that I fancy we shall disagree, but in the descriptive part our 

 agreement has been eminently satisfactory to me, and far more than 

 I ever ventured to anticipate. I consider that now the subsidence 

 theory is established. I have read about half through the descriptive 

 part of the Volcanic Geology (last night I ascended the peaks of Tahiti 

 with you, and what I saw in my short excursion was most vividly 

 brought before me by your descriptions), and have been most deeply 

 interested by it. Your observations on the Sandwich craters strike 

 me as the most important and original of any that I have read for a 

 long time. Now that I have read yours, I believe I saw at the Gala- 

 pagos, at a distance, instances of those most curious fissures of erup- 

 tion. There are many points of resemblance between the Galapagos 

 and Sandwich Islands (even to the shape of the mound-like hills) 

 viz., in the liquidity of the lavas, absence of scoria?, and tuff-craters, 

 Many of your scattered remarks on denudation have particularly inter- 

 ested me ; but I see that you attribute less to sea and more to running 

 water than I have been accustomed to do. After your remarks in your 

 last very kind letter I could not help skipping on to the Australian 

 valleys, on which your remarks strike me as exceedingly ingenious and 

 novel, but they have not converted me. I can not conceive how the 

 great lateral bays could have been scooped out, and their sides ren- 

 dered precipitous by running water. I shall go on and read every 

 word of your excellent volume. 



If you look over my Geological Instructions you will be amused 

 to see that I urge attention to several points which you have elab- 

 orately discussed. I lately read a paper of yours on Chambers' book, 



vol. lxh. 26. 



