CHARLES DARWIN TO ASA GRAY. April 4th [1859].
...You ask to see my sheets as printed off; I assure you that it will be the HIGHEST satisfaction to me to do so: I look at the request as a high compliment. I shall not, you may depend, forget a request which I look at as a favour. But (and it is a heavy "but" to me) it will be long before I go to press; I can truly say I am NEVER idle; indeed, I work too hard for my much weakened health; yet I can do only three hours of work daily, and I cannot at all see when I shall have finished: I have done eleven long chapters, but I have got some other very difficult ones: as palaeontology, classifications, and embryology, etc., and I have to correct and add largely to all those done. I find, alas! each chapter takes me on an average three months, so slow I am. There is no end to the necessary digressions. I have just finished a chapter on Instinct, and here I found grappling with such a subject as bees' cells, and comparing all my notes made during twenty years, took up a despairing length of