RECORD: Darwin, C. R. [1852]. [Notes on the chain for the well at Down House]. Carroll5. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Photographed by Angus Carroll. Transcribed and edited by John van Wyhe 5.2021. RN1
NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with the kind permission of Angus Carroll and William Huxley Darwin.
This manuscript in a private collection contains calculations by Darwin on the weight of the chain or cable used by his servants to draw water in a bucket from the deep well at Down House. There is a manuscript in Darwin's hand at Down House (EH88202558.2) which is closely associated with this one. It records changes to the weight of chain or cable used for the well over several years. Darwin continually tried to lighten the weight of the cable and bucket used in his well. One late note is dated 17 July 1852 with "Wire rope weighs 50lb". This new weight is exactly what is used in the calculations in this manuscript. Darwin continued to try new materials to lighten the very heavy chain and bucket for his well.
See the related articles by Darwin: Bucket ropes for wells. Gardeners' Chronicle. Text F1680 and: The subject of deep wells. Gardeners' Chronicle. Text F1696
[1]
F. : W :: BC. : CA.
BC = 19 1/8 of [illeg] CA = 134 1/8
19 : 1343 :: F : W.
19) 135 [-] 133 [=] 1 (7. = W
—————————————————
W : W' :: FF : ED (FE=60) FD = 144
7 : W' :: 60 : 144
60 : 144 :: 7 : W' = 16.8
1008.0 [÷] 60 [=] 16.8
By measuring circumference & length of chain hauled up w'[dth] = 15.94
————
If 16 men can pull 120lb at desired [rate?], how many men can pull 50lb.
120lb : 50lb :: 16 men : X
Whatever X may be (as there will be only one man) his force must be [illeg] as ratio of 1 to X [illeg] of as now 1:16
[1v]
6.6 : 105.2 :: F : W'
105.2 [÷] 6.6 [=] 15.94
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 24 February, 2024