[The few sentences in the autobiographical chapter give with sufficient clearness the connection between the 'Power of Movement,' and one of the author's earlier books, that on 'Climbing Plants.' The central idea of the book is that the movements of plants in relation to light, gravitation, etc., are modifications of a spontaneous tendency to revolve or circumnutate, which is widely inherent in the growing parts of plants.
This conception has not been generally adopted, and has not taken a place among the canons of orthodox physiology. The book has been treated by Professor Sachs with a few words of professorial contempt; and by Professor Wiesner it has been honoured by careful and generously expressed criticism.
Mr. Thiselton Dyer ('Charles Darwin' ('Nature' Series), page 41.) has well said: "Whether this masterly conception of the unity of what has hitherto seemed a chaos of unrelated phenomena will be sustained, time alone will show. But no one can doubt the importance of what Mr. Darwin has done, in showing that for the future the phenomena of plant movement can and indeed must be studied from a single point of view."The work was begun in the summer of 1877, after the publication of 'Different Forms of Flowers,' and by the autumn his enthusiasm for the subject was thoroughly established, and he wrote to Mr. Dyer: "I am all on fire at the work." At this time he was studying the movements of cotyledons, in which the sleep of plants is to be observed in its ******st form; in the following spring he was trying to discover what useful purpose these sleep-movements could serve, and wrote to Sir Joseph Hooker (March 25th, 1878):--"I think we have PROVED that the sleep of plants is to lessen the injury to the leaves from radiation. This has interested me much, and has cost us great labour, as it has been a problem since the time of Linnaeus. But we have killed or badly injured a multitude of plants: N.B.--Oxalis carnosa was most valuable, but last night was killed."His letters of this period do not give any connected account of the progress of the work. The two following are given as being characteristic of the author:]
CHARLES DARWIN TO W. THISELTON DYER.
Down, June 2, 1878.
My dear Dyer, I remember saying that I should die a disgraced man if I did not observe a seedling Cactus and Cycas, and you have saved me from this horrible fate, as they move splendidly and normally. But I have two questions to ask: the Cycas observed was a huge seed in a broad and very shallow pot with cocoa-nut fibre as I suppose. It was named only Cycas. Was it Cycas pectinata? I suppose that I cannot be wrong in believing that what first appears above ground is a true leaf, for I can see no stem or axis.
Lastly, you may remember that I said that we could not raise Opuntia nigricans; now I must confess to a piece of stupidity; one did come up, but my gardener and self stared at it, and concluded that it could not be a seedling Opuntia, but now that I have seen one of O. basilaris, I am sure it was; I observed it only casually, and saw movements, which makes me wish to observe carefully another. If you have any fruit, will Mr. Lynch (Mr. R.I. Lynch, now Curator of the Botanic Garden at Cambridge was at this time in the Royal Gardens, Kew.) be so kind as to send one more?
I am working away like a slave at radicles [roots] and at movements of true leaves, for I have pretty well done with cotyledons...
That was an EXCELLENT letter about the Gardens (This refers to an attempt to induce the Government to open the Royal Gardens at Kew in the morning.):
I had hoped that the agitation was over. Politicians are a poor truckling lot, for [they] must see the wretched effects of keeping the gardens open all day long.
Your ever troublesome friend, CH. DARWIN.
CHARLES DARWIN TO W. THISELTON DYER.
4 Bryanston St., Portman Square, November 21 [1878].
My dear Dyer, I must thank you for all the wonderful trouble which you have taken about the seeds of Impatiens, and on scores of other occasions. It in truth makes me feel ashamed of myself, and I cannot help thinking: "Oh Lord, when he sees our book he will cry out, is this all for which I have helped so much!" In seriousness, I hope that we have made out some points, but Ifear that we have done very little for the labour which we have expended on our work. We are here for a week for a little rest, which I needed.
If I remember right, November 30th, is the anniversary at the Royal, and Ifear Sir Joseph must be almost at the last gasp. I shall be glad when he is no longer President.
Yours very sincerely, CH. DARWIN.
[In the spring of the following year, 1879. When he was engaged in putting his results together, he wrote somewhat despondingly to Mr. Dyer: "I am overwhelmed with my notes, and almost too old to undertake the job which Ihave in hand--i.e. movements of all kinds. Yet it is worse to be idle."Later on in the year, when the work was approaching completion, he wrote to Prof. Carus (July 17, 1879), with respect to a translation:--"Together with my son Francis, I am preparing a rather large volume on the general movements of Plants, and I think that we have made out a good many new points and views.
"I fear that our views will meet a good deal of opposition in Germany; but we have been working very hard for some years at the subject.
"I shall be MUCH pleased if you think the book worth translating, and proof-sheets shall be sent you, whenever they are ready."In the autumn he was hard at work on the manuscript, and wrote to Dr. Gray (October 24, 1879):--"I have written a rather big book--more is the pity--on the movements of plants, and I am now just beginning to go over the MS. for the second time, which is a horrid bore."Only the concluding part of the next letter refers to the 'Power of Movements':]
CHARLES DARWIN TO A. DE CANDOLLE.
May 28, 1880.