From H. C. Sorby 28 December 1881
Broomfield | Sheffield
Dec 28/81
My dear Mr. Darwin
Judging from what you say there appears to be no red colouring matter present in the plant that could be turned blue by the neutralization of free acid.1 I therefore suspect that the change is analogous to one that often occurs in more or less alkaline solutions. In most cases that I examined I was of opinion that the production of the colouring matter was due to the oxidization by the air of one or other of the different kinds of tannic acid but I am quite prepared to believe that other substances have the same sort of property and feel almost certain that this is so in the case of many lichens.2 On the whole I venture to suggest that the plant contains something changed into the colouring matter when in a slightly alkaline solution. If you could send me a little of the fresh plant I could make it out more certainly
I left off studying the colouring matters of plants in order to work up all the material I had collected for my two addresses at the Geological Society on the structure of rocks and since then have been led into a whole lot of new work by living on my yacht nearly half the year.3 The first few years I was learning what to do. The last I have done a fair lot of scientific work. Along with Prof. Herdman my first paper will soon appear on a number of new British Ascidians.4 I have splendid opportunities for collecting and observing and in a while hope to do good service to science in this department. I should do more if my attention were not so much directed to a sort of compound of art and science—art illustrating science and science helping art—which however is I hope useful in another department of knowledge. If I can in any way assist you in connexion with marine work in the English Channel &c I shall be very pleased and if you could suggest anything that it would be desirable to examine I should be very much obliged. I am attending to nearly all departments of scientific work along with the best authorities in each branch.
Trusting that you are well and being always most glad to do any little thing I can to advance the great questions you have so constantly in hand; wishing you a happy new year | I remain | Yours very truly | H C. Sorby
Footnotes
Bibliography
ODNB: Oxford dictionary of national biography: from the earliest times to the year 2000. (Revised edition.) Edited by H. C. G. Matthew and Brian Harrison. 60 vols. and index. Oxford: Oxford University Press. 2004.
Sorby, Henry Clifton. 1879. Anniversary address of the president. [Read 21 February 1879.] Proceedings of the Geological Society of London 35: 9–95.
Sorby, Henry Clifton. 1880. On the structure and origin of non-calcareous stratified rocks. [Read 20 February 1880.] Proceedings of the Geological Society of London 36 (1879–80): 46–92.
Sorby, Henry Clifton and Herdman, William Abbott. 1882. On the ascidians collected during the cruise of the yacht ‘Glimpse’. [Read 1 June 1882.] Journal of the Linnean Society (Zoology) 16 (1881–3): 527–36.
Summary
Discusses colour changes of plant colouring material.
Is doing much marine work from his yacht; asks whether CD has any suggestions for profitable observations.
Letter details
- Letter no.
- DCP-LETT-13585
- From
- Henry Clifton Sorby
- To
- Charles Robert Darwin
- Sent from
- Broomfield, Sheffield
- Source of text
- DAR 177: 219
- Physical description
- ALS 7pp
Please cite as
Darwin Correspondence Project, “Letter no. 13585,” accessed on 28 March 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-13585.xml