To Nicolai Krohn   18 December 18811

[4 Bryanston Street, London.]

[…] The number of worms in your garden is astonishing […] it will be an interesting observation, how soon the land is again stocked with worms, & whether the grass grows better before this happens.—2 I neglected to observe whether worms distruct[?] the roots of grasses.— You will probably be able to borrow […] my book ‘On the Formation of Vegetable Mould’ […] in which […] you will find a good deal about the natural history of worms3 […]

The date is provided by the sale catalogue; according the catalogue, the letter was addressed from Down.
See letter from Nicolai Krohn, 16 December 1881 and n. 1. Krohn had watered his lawn with a solution of perchloride of mercury, and observed a large number of dying earthworms emerge from underground.
Krohn mistakenly thought that CD had written an article in The Times on earthworms and had asked CD for a reference (see letter from Nicolai Krohn, 16 December 1881 and n. 2). Earthworms was published on 10 October 1881 (Freeman 1977).
The original letter is complete and according to the sale catalogue is two pages long.

Please cite as “DCP-LETT-13561,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-13561