read and re-read as a youth his 'Personal Narrative.' How true and pleasing are all your remarks on his kindness; think how many opportunities you will have, in your new place, of being a Humboldt to others. Ask him about the river in N.E. Europe, with the Flora very different on its opposite banks. I have got and read your Wilkes; what a feeble book in matter and style, and how splendidly got up! Do write me a line from Berlin. Also thanks for the proof-sheets. I do not, however, mean proof plates; I value them, as saving me copying extracts. Farewell, my dear Hooker, with a heavy heart I wish you joy of your prospects. Your sincere friend, C. DARWIN. [The second edition of the 'Journal,' to which the following letter refers, was completed between April 25th and August 25th. It was published by Mr. Murray in the 'Colonial and Home Library,' and in this more accessible form soon had a large sale. Up to the time of his first negotiations with Mr. Murray for its publication in this form, he had received payment only in the form of a large number of presentation copies, and he seems to have been glad to sell the copyright of the second edition to Mr. Murray for 150 pounds. The points of difference between it and the first edition are of interest chiefly in connection with the growth of the author's views on evolution, and will be considered later.] CHARLES DARWIN TO C. LYELL. Down [July, 1845]. My dear Lyell, I send you the first part (No doubt proof-sheets.) of the new edition [of the 'Journal of Researches'], which I so entirely owe to you. You will see that I have ventured to dedicate it to you (The dedication of the second edition of the 'Journal of Researches,' is as follows:--"To Charles Lyell, Esq., F.R.S., this second edition is dedicated with grateful pleasure--as an acknowledgment that the chief part of whatever scientific merit this Journal and the other works of the Author may possess, has been derived from studying the well-known and admirable 'Principles of Geology.'"), and I trust that this cannot be disagreeable. I have long wished, not so much for your sake, as for my own feelings of honesty, to acknowledge more plainly than by mere reference, how much I geologically owe you. Those authors, however, who like you, educate people's minds as well as teach them special facts, can never, I should think, have full justice done them except by posterity, for the mind thus insensibly improved can hardly perceive its own upward ascent. I had intended putting in the present acknowledgment in the third part of my Geology, but its sale is so exceedingly small that I should not have had the satisfaction of thinking that as far as lay in my power I had owned, though imperfectly, my debt. Pray do not think that I am so silly, as to suppose that my dedication can any ways gratify you, except so far as I trust you will receive it, as a most sincere mark of my gratitude and friendship. I think I have improved