RECORD: Darwin, C. R. n.d. (calculations). CUL-DAR60.1.55-57. (John van Wyhe ed., 2002-. The Complete Work of Charles Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Text prepared and edited by John van Wyhe. 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-DAR 54-61 contain material for Darwin's book Insectivorous plants (1875).
55
1 gr to 1 oz.
8 drach [x] 60 [=] 480 minim [x] 60 [=] 28800 (1/2 of this = 1/14,400 [x] 3 tentacles touched [=] 86,4—
When 1 gr 2 gr to 2 oz 1 oz used & 3 hairs tentacles touched the quantity 1/43,200 of grain
1 1/2 [=] 64800 to 1 oz
1 1/2 gr to 1 oz of water applied to 3 tentacles
1/64.800 of a grain
1 2 gr to 2 oz of water
86,400 [x] 2 [=] 172800 173800 1/172,800 173800
55v
480 mnms [x] 2 [=] 960 1/2 m.
4/960 = 1/240 280
960 [÷] 2 [=] 480
1/960 1/2 minm [x] 3 [=] 2880
56
Sept 7)
5 leaves & 30 minm
18 oz [x] 8 [=] 146 drach [x] 10 [=] 1460 → 6 minims or 1/5' of 30 minm given to 5 leaves
p. 15)
so each leaf got 1/1460 of gr.
1460 [x] 150 assumed glands [=] 219,000 ie each gland got 1/219,000 of gr. with action of Crys.
4 leaves & 40 minim
p. 15)
24 oz [x] 8 [=] 192 drachm [x] 6 [=] 1152 → 10 minims (illegible) or 1/4 of 40 minim to 4 leaves
so each leaf got 1/1152 of gr.
1152 [x] 150 [=] 172,800 so each gland got 1/172,800 of gr (or 1/184,320 if taking 160 glands to leaves.)
57
1152 [x] 160 glands [=] 184,320
{ 2 leaves 15 minim 2 leaves 10 minim
5 leaves)
p. 17
30 oz [x] 8 [=] 240 drach [x] 10 [=] 2400 — as each leaf got 6 minims or 1/5 of 30 minm.
so each leaf got 1/2400
2400 [x] 160 glands [=] 384,000
so 1/384,000 affected several glands & all on one leaf.
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 1 December, 2025