My dear M^r Whewell

I have taken the whole day to consider the proposal, which you have made me in so kind a manner. I fully agree with you, in the advantages it offers, counterbalanced however by a considerable share of evil; but independently of these personal considerations, I think it is the duty of every geologist to follow your example, and that of the others, which you named, in sacrificing his time to the Society.¹ But as I am just at present situated, I really cannot accept the office.— I have to write the third volume of Capt. FitzRoy’s account of our expedition. He is already before hand with me, and I fear that even with giving up all details in Natural History, I shall be the cause of delay.² Could I then undertake an employment, which must take up a considerable portion of time?

I am not accustomed to write, and still less to use the faculty of digestion in that high degree, which drawing up even small reports, requires. The difficulty would be also to me greater from my ignorance of English geology. After my first work is completed, in which I am not independent, I shall be happy to be of assistance in any way, which you could suggest, & which would not take up too large a portion of time. But pray remember how young a member I am, and how little I know of that kind of geology, or of general business, which would be most serviceable. I suppose, I ought to feel most regret, at being compelled to refuse my service, little as it would be, to so good a cause, as geology, but I feel far more, in not at once acceding to anything proposed by you, who have, since my return, shewn so much interest and kindness in all my affairs.— I trust you will not think, that I have acted entirely from selfish motives.— You probably will hardly be able to comprehend, that such a trifling loss of time, as the secretaryship would require, could be any serious evil, but in my own case, where work done bears a small proportion to time spent, the case would be very different.

I must again repeat my best thanks for the offer, which I cannot take otherwise, than as a high compliment, and believe me, my dear M^r Whewell | Yours most truly obliged | Chas. Darwin Friday Evening