I have corrected all but the last two chapters of my book, and hope to have done revises and all in about three weeks, and then I (or we all) shall start for some months' hydropathy; my health has been very bad, and I am becoming as weak as a child, and incapable of doing anything whatever, except my three hours daily work at proof-sheets. God knows whether I shall ever be good at anything again, perhaps a long rest and hydropathy may do something.
I have not had A. Gray's Essay, and should not feel up to criticise it, even if I had the impertinence and courage. You will believe me that I speak strictly the truth when I say that your Australian Essay is EXTREMELY interesting to me, rather too much so. I enjoy reading it over, and if you think my criticisms are worth anything to you, I beg you to send the sheets (if you can give me time for good days); but unless I can render you any little, however little assistance, I would rather read the essay when published. Pray understand that I should be TRULY vexed not to read them, if you wish it for your own sake.
I had a terribly long fit of sickness yesterday, which makes the world rather extra gloomy to-day, and I have an insanely strong wish to finish my accursed book, such corrections every page has required as I never saw before. It is so weariful, killing the whole afternoon, after 12 o'clock doing nothing whatever. But I will grumble no more. So farewell, we shall meet in the winter I trust.
Farewell, my dear Hooker, your affectionate friend, C. DARWIN.
CHARLES DARWIN TO C. LYELL. Down, September 2nd [1859].
...I am very glad you wish to see my clean sheets: I should have offered them, but did not know whether it would bore you; I wrote by this