# To Edward Cresy   [12 November 1860]1

Down, Bromley, Kent

Monday night

Dear Cresy

Upon my life I think you must be the most good-natured man in the world. How capitally you have answered the question about the weight of water; you are as good, indeed a great deal better, than an Encyclopedia. How fortunate for me that I asked you about Hofman’s note. What a horrid blunder I should have made! But what trouble you have taken for me.—   About the measure and weights I daresay your explanation is quite right, for I looked into old and new books; but there were also most stupid misprints.—   I shall permanently keep your letter.2

As you seem a little interested about Drosera, I may mention that today I have been testing how light a weight will set a single hair moving, and I find $\frac{1}{50}$ of an inch of finest cotton thread suffices and rather shorter length (measured by micrometer) of my wife’s hair suffices; and I have sent today several inches of both to be weighed by good balance in Jermyn St.;3 and the result will show a very small fraction of a grain; so that the hairs are as sensitive to mechanical as to chemical action.— All the wild Droseras, I find, are dead for this year; so I must now write my paper and cannot try a few more experiments, as I much wished to do.

I have been much amused by your account of your conversation with Woodward and I should much like to hear you take him off. He is a very good man in his way, and his generalisations on Shells are really capital.4

We returned home on Saturday evening; and my girl stood the journey well; but she is very weak.

With hearty thanks | Yours very sincerely | C. Darwin

## Footnotes

Dated by the relationship to the letter from Edward Cresy, 10 November 1860, and to CD’s return to Down on Saturday, 10 November (‘Journal’; Appendix II).
See letter from Trenham Reeks, 15 November 1860. Reeks worked at the Museum of Practical Geology in Jermyn Street, London.
See letter from Edward Cresy, 10 November 1860. CD refers to Samuel Pickworth Woodward’s treatise on the Mollusca (S. P. Woodward 1851–6), which he had read and praised in 1856 (see Correspondence vol. 4, Appendix IV, 128: 18; and vol. 6, letter to S. P. Woodward, 15 May [1856]). There is an annotated copy of the work in the Darwin Library–CUL.

## Bibliography

Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 27 vols to date. Cambridge: Cambridge University Press. 1985–.

Woodward, Samuel Pickworth. 1851–6. A manual of the Mollusca; or, a rudimentary treatise of recent and fossil shells. 3 pts. London. [Vols. 6,8,9]

## Summary

Thanks for information about the weight of water.

Describes experiments on Drosera.

## Letter details

Letter no.
DCP-LETT-2620
From
Charles Robert Darwin
To
Edward Cresy, Jr
Sent from
Down
Source of text
DAR 143
Physical description
2pp