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.


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Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

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