My dear Sir

Enclosed is the Diagram which I wish engraved on Copper on folding out Plate to face latter part of volume.—¹ It is an odd looking affair, but is indispensable to show the nature of the very complex affinities of past & present animals.— I have given full instructions to Engraver, but must see a Proof.—²

A perfect shower of proof-sheets have arrived, (thanks to you) to my great satisfaction;³ but I find that my M.S, which I thought was pretty clear is very obscure, & I am sorry to say, both for time & expence sake, that my corrections are rather heavy, & will take me much longer time than I anticipated: I have informed M^ess ^rs. Clowes of this, that they may not lock up too much type.⁴

I think you wished to know when 8 or 10 sheets were completed & I will inform you.—

I am much obliged for your curious extract about the Mice.

A week of Hydropathy at Moor Park has done me a world of good.—

Pray believe me | My dear Sir | Yours very sincerely | C. Darwin

P.S Please to specify for Engraver height of page, which I can see, is enough for Diagram without horizontal fold.

P.S | If you much object to Plate, as too long, if printed on paper blank on one side so as to unfold clean out, I will give up: perhaps it will make the folding too complicated, but on that head you can judge.—

It has to be referred to in three parts of my volume.—