skip to content

Darwin Correspondence Project

From Edward Frankland   15 July 1873

Royal College of Chemistry | Kensington Museum

July 15/73.

My dear Sir

I shall deem it a privilege if I can be of any service to you in your very interesting investigations of Drosera. Herewith I forward some pure carbonate of soda (which I prefer to carbonate of ammonia) and if you will wash the glands in about 20 grams of it dissolved in 1 oz. of distilled water, I will do my best to discover what the solvent you mention consists of.1 I fear it will be necessary to wash a very large number of leaflets, say 8 oz. or so, to get a sufficiently concentrated solution.2

I should not think muriatic acid probable, but possibly formic, acetic, oxalic or lactic acid may be present.3 However we must not prejudge the case.

Believe me | Yours sincerely | E. Frankland


CD was investigating the chemical composition of the digestive fluid in Drosera (see letter to Edward Frankland, 12 July 1873).
In Insectivorous plants, p. 88, CD described washing 445 leaves in a solution of distilled water given to him by Frankland.


Insectivorous plants. By Charles Darwin. London: John Murray. 1875.


Sends sodium carbonate for Drosera experiments. Will try to determine what the solvent is.

Letter details

Letter no.
Edward Frankland
Charles Robert Darwin
Sent from
R. Coll. Chem.
Source of text
DAR 164: 206
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 8979,” accessed on 18 April 2021,

Also published in The Correspondence of Charles Darwin, vol. 21