RECORD: Darwin, C. R. 1879.03.06. Beans / Radicles / Sensitiveness to contact. CUL-DAR209.5.37-38. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 5.2023. 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 volume CUL-DAR209.5 contains materials for Darwin's book Movement in plants (1880).


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March 6th 1879. Radicles Beans Sensitiveness to contact.

Bean germinated at in wet fine red sand. Temp of room range only 1° from 59°F.— Suspended with cards attached. Temp. 52° 1/2 to Cards & touches of shell-lac all on right side of apex of R.— bean facing me in usual manner.

8° 5' a.m

(1) with card & shell-lac X — 4° 35' P.m. & curved (7th. 7° 45' a.m now straight

(2) like (1) (7th 8° a.m decidedly curved from sqr) X

(3) (like 1) 4° 35 almost rectangular X (7th. 8° a.m almost straight

(4) like (1) 4° 35 doubtfully curved — (7th 8° am very slight affected) 7th 4° 30 put on gum & card 8th 8' a.m cu much curved X

(5) like (1) (7th 8° a.m curved at 45° from perpendicular & from card) X

(6) like (1) 4° 35 a trace of little curvature (7th curved but almost in direction of Sach. X?

Slip

(7) touched with shell-lac a little spread on sqr of card & then apex touched with the card

7th 8° a m no effect — 4° 30 put on gum & card 8th 8° a.m greatly curved X card dropped off

(8) (like 7) (7th 8° a.m no effect

(over)

[1v]

(Conclusion)

This paper is conclusive that shell-lac by itself causes very slight movement— The 2 which acted have been sent to Leonard to weigh.— All then can be said that with the scale which at the time I could use turned fairly well with 1/100 of grain. & the two little bits together hardly showed any movement ∴ less than 1/200 of grain!!!

It further shows that now in spring the little square of card whether shell-lacced or gummed on act as perfectly as before— Insist on mysterious condition which in winter stopped them acting— was it cold at night.— or did I keep them too warm.—

(I subsequently tried 4 radicles of Beans which had germinated after all the others & which grew slowly, though apparently healthy, & after affixing cards with gum even after 24 h were hardly at all acted on— slow growing seems to interfere with sensibility & this throws light on results in dead of winter.

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March 6 — 1879 continued

(9) (like 7) (7th 8° am no effect), put on card with gum, 4° 30' P.m much curved from card about 45 X

(10) (like 7) 6th 4° 35' P.m only little X curved (7th 8° a.m no effect now): put on card & gum. 4°. 30' P.m curved almost at rt angles from card X

11. (like 7) 7th 8° a.m no effect: put on card & gum 4° 30' P.m curved almost at right angles X

12 like (7) 4° 35. decidedly curved X (7th 8° a.m 23° now quite straight): put on card & gum, 4° 30 curved about at right angles X

13 (like 7) (7th 8° a.m quite straight: put on card & gum, 4° 30' P.m slipped down parallel no effect; fixed again 4° 30' put on gum & card.

14 (like 7) (7th 8° am quite straight

15 (like 7) (7th 8° am quite straight

N.B The difference of the 6 with square & the 9 with many shell-lac conspicuously great.

7th

8° 5'

Put on gum & cards on several for drawing after removing shell lac


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

File last updated 25 July, 2023