From L. J. Jones   1 November [1881]1

102 Mount St. | London, W.

Nov 1st,

Dear Sir.

On page 165 of your recent work on Vegetable Mould the number of pounds ejected per square yard is given as 83.87. This is an obvious misprint, & I at first thought that the decimal point had slipped into the wrong place. The total however of 18.12 tons per acre gives, it seems to me 8.353 lbs per sq. yd. instead of 8.387.2

I am unable to arrive at quite the same total from the data given on the preceding page, as

1lb. 1312oz for 12 of 36545 days

= 7.477 lbs. per sq. yd.3

The deep interest with which I have read your book and the importance of accuracy in details of which it is so signal a proof must be my excuse for troubling you on a point which has probably attracted your attention long before this.

I remain | your obedt. servant | Lawrence J Jones.

CD annotations

Top of letter: ‘Very important | Look to | original | notes’ blue crayon; ‘The tables will have to | be corrected’4 blue ink
The year is established by the relationship between this letter and the letter to L. J. Jones, 2 November 1881.
The figure of 83.87 pounds per square yard was given in Earthworms, p. 165; this was corrected to 8.387 in the fourth thousand.
In Earthworms, p. 164, CD gave the weight of castings as 1lb 1312oz. This remained unchanged in later printings.
The annotations are for CD’s reply (letter to L. J. Jones, 2 November 1881).

Please cite as “DCP-LETT-13449,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-13449