Dear Sir

I beg permission to thank you sincerely for sending me your “Notes on animal Life at vast Depths”.² It has interested me extremely.

You have indeed made a grand beginning at an admirable field of research.

If you would not think me very unreasonable, you would do me a great favour, if you would inform me on one point not noticed in your Notes. In the account given in the Times, it is stated that the Machine or Borer either often or sometimes penetrated through the Foraminiferous deposit into different underlying matter.³ This would show that the Foraminiferous deposit was sometimes or often thin; & this is the point on which I am anxious for information.— It bears on the decay of the exuviæ of organisms at the bottom of the sea; & is important for me in relation to some few passages in my Book on the Origin of Species, of which I am now preparing a corrected Edition.—⁴

You allude, also, to bare rock at the bottom of the sea. Have you any reason to believe that extensive areas are bare?—   About the Borer I had with hesitation thought of quoting the Times; but if the facts are true, I sh^d. of course infinitely prefer just alluding to the case on your authority.⁵

What a wonderful fact about the Ophiuræ, & what a capital proof of the Foraminifera having been alive is their discovery in their stomachs.⁶

Do you not think that you are rather bold in inferring that the basaltic pebbles were rounded at such great depths? Are you sure they were not dropped by icebergs either recently or at the close of the Glacial period?

With my best thanks & apologies for troubling you, I remain, | Dear Sir, | Yours very faithfully | C. Darwin

P.S. | Is it not a most curious fact that the water at such profound depths, & under such a vast pressure, should retain Oxygen for the respiration of the animals mentioned by you?