The Complete Work of Charles Darwin Online

RECORD: Darwin, C. R. [1873?].08.23-24. Vine leaves. CUL-DAR66.16. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 3.2023. 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-DAR66 contains notes on 'bloom'. Francis Darwin explained: "His researches into the meaning of the 'bloom,' or waxy coating found on many leaves, was one of those inquiries which remained unfinished at the time of his death. He amassed a quantity of notes on the subject". LL3: 339. See an Introduction to these folders by Christine Chua & John van Wyhe.

[16]

✔ (Vine leaves)

Aug 23d 3˚Pm. put 4 vine leaves in a little distilled water in wine glass, & kept up temp from 71° to 79°, generally about 75° — On 24th at 10˚ A.m. found water slightly discoloured & acid, & coloured litmus, & all the parts of leaves which had been immersed became quite brown. —(Pressed down by zinc could zinc be cause?)

Put in Drosera leaf at 5˚ P.m. some inflection (ie after 7˚) & on 24' at 9˚ very considerable inflection I suspect some albumen exuded

Can cause be that leaf cut off as here shows that most leaves attached to stems can so long be immersed

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