To L. C. Wedgwood 21 January [1872]1
Down.—
Jan 21st
My dear Lucy
You are worth your weight in Gold.— I looked at a good many holes, but kept no account, & it tires my head stooping. It seems natural they shd come on average more often at right angles than oblique, to surface; but whether I shall be able to form a judgment I know not.—2 I shall be very glad to hear any further observation, & about furrows. It is at present all working in the dark.— I am now getting more inclined to trust the result of trenches cut across old furrows on nearly level surface; or to upper & lower part of grass-slope with no old furrows.
I have had some curious observations from Wroxeter, & William is working at Stonehenge for me.—3 I hope in time to come to some approximately safe conclusion.
If worms would be so good as to come up generally at right angles to slope, it would bring the earth down grandly. By the way I suppose when you say “vertical to the slope” you mean perpendicular or at right angles to the slope. The Mathematician George4 says vertical always relates to the horizon, so you ought to hide your diminished head.
Yours affectionately | C. Darwin
I find after the late heavy wind & rain the soft subsided castings are much ‘blown over to leeward, even on level grass-field; the sections of all the recent castings were thus

Would you visit the common on Leith Hill when you go home, & look at castings; the late storms must have blown there with terrific force.—5
Footnotes
Bibliography
Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.
Earthworms: The formation of vegetable mould through the action of worms: with observations on their habits. By Charles Darwin. London: John Murray. 1881.
Summary
Thanks for observations on angles of worm-holes on slopes. William Darwin is observing at Stonehenge. She is worth her weight in gold.
Letter details
- Letter no.
- DCP-LETT-8171
- From
- Charles Robert Darwin
- To
- Lucy Caroline Wedgwood/Lucy Caroline Harrison
- Sent from
- Down
- Source of text
- Cambridge University Library (Add 4251: 332)
- Physical description
- ALS 4pp
Please cite as
Darwin Correspondence Project, “Letter no. 8171,” accessed on 26 September 2022, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-8171.xml
Also published in The Correspondence of Charles Darwin, vol. 20