RECORD: Darwin, C. R. and William E. Darwin. n.d. [Amount of earth to cross a base line per annum]. CUL-DAR63.68. Edited by John van Wyhe (The Complete Work of Charles Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 6.2021. RN1
NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volumes CUL-DAR63, CUL-DAR64 and CUL-DAR65 contain a diverse array of materials for Darwin's research on earthworms. All of the textual items in these folders, including this one, have been transcribed in a single file: CUL-DAR63-65.
1
Suppose a square acre to be marked out on the sloping field then the base line marked out along the foot of the slope well be 70 yards long. The 168 cubic inches of earth will cross this base line per annum.
Generally mark a level line on the side of the hill of given length (say a yard) estimate how much earth crosses that line per annum.
1v
Fig. 1
Fig. 2
arrangement of Plate IV
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 3 July, 2025