1880.
[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
simplest 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 I fear 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
I fear 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 I have 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.
My dear Sir,
I am particularly obliged to you for having so kindly send me your
'Phytographie' (A book on the methods of botanical research, more
especially of systematic work.); for if I had merely seen it advertised,
I should not have supposed that it could have concerned me. As it is, I
have read with very great interest about a quarter, but will not
delay longer thanking you. All that you say seems to me very clear
and convincing, and as in all your writings I find a large number of
philosophical remarks new to me, and no doubt shall find many more. They
have recalled many a puzzle through which I passed when monographing the
Cirripedia; and your book in those days would have been quite invaluable
to me. It has pleased me to find that I have always followed your plan
of making notes on separate pieces of paper; I keep several scores of
large portfolios, arranged on very thin shelves about two inches apart,
fastened to the walls of my study, and each shelf has its proper name
or title; and I can thus put at once every memorandum into its proper
place. Your book will, I am sure, be very useful to many young students,
and I shall beg my son Francis (who intends to devote himself to the
physiology of plants) to read it carefully.
As for myself I am taking a fortnight's rest, after sending a pile of
MS. to the printers, and it was a piece of good fortune that your book
arrived as I was getting into my carriage, for I wanted something to
read whilst away from home. My MS. relates to the movements of plants,
and I think that I have succeeded in showing that all the more important
great classes of movements are due to the modification of a kind of
movement common to all parts of all plants from their earliest youth.
Pray give my kind remembrances to your son, and with my highest respect
and best thanks,
Believe me, my dear Sir, yours very sincerely, CHARLES DARWIN.
P.S.--It always pleases me to exalt plants in the organic scale, and if
you will take the trouble to read my last chapter when my book (which
will be sadly too big) is published and sent to you, I hope and think
that you also will admire some of the beautiful adaptations by which
seedling plants are enabled to perform their proper functions.
[The book was published on November 6, 1880, and 1500 copies were
disposed of at Mr. Murray's sale. With regard to it he wrote to Sir J.D.
Hooker (November 23):--
"Your note has pleased me much--for I did not expect that you would have
had time to read ANY of it. Read the last chapter, and you will know the
whole result, but without the evidence. The case, however, of radicles
bending after exposure for an hour to geotropism, with their tips (or
brains) cut off is, I think, worth your reading (bottom of page 525); it
astounded me. The next most remarkable fact, as it appeared to me (page
148), is the discrimination of the tip of the radicle between a slightly
harder and softer object affixed on opposite sides of tip. But I will
bother you no more about my book. The sensitiveness of seedlings to
light is marvellous."
To another friend, Mr. Thiselton Dyer, he wrote (November 28, 1880):--
"Very many thanks for your most kind note, but you think too highly of
our work, not but what this is very pleasant... Many of the Germans are
very contemptuous about making out the use of organs; but they may sneer
the souls out of their bodies, and I for one shall think it the most
interesting part of Natural History. Indeed you are greatly mistaken if
you doubt for one moment on the very great value of your constant and
most kind assistance to us."
The book was widely reviewed, and excited much interest among the
general public. The following letter refers to a leading article in the
"Times", November 20, 1880:]
CHARLES DARWIN TO MRS. HALIBURTON. (Mrs. Haliburton was a daughter of my
father's early friend, the late Mr. Owen, of Woodhouse.) Down, November
22, 1880.
My dear Sarah,
You see how audaciously I begin; but I have always loved and shall
ever love this name. Your letter has done more than please me, for its
kindness has touched my heart. I often think of old days and of the
delight of my visits to Woodhouse, and of the deep debt of gratitude
I owe to your father. It was very good of you to write. I had quite
forgotten my old ambition about the Shrewsbury newspaper (Mrs.
Haliburton had reminded him of his saying as a boy that if Eddowes'
newspaper ever alluded to him as "our deserving fellow-townsman," his
ambition would be amply gratified.); but I remember the pride which I
felt when I saw in a book about beetles the impressive words "captured
by C. Darwin." Captured sounded so grand compared with caught. This
seemed to me glory enough for any man! I do not know in the least what
made the "Times" glorify me (The following is the opening sentence
of the leading article:--"Of all our living men of science none have
laboured longer and to more splendid purpose than Mr. Darwin."), for it
has sometimes pitched into me ferociously.
I should very much like to see you again, but you would find a visit
here very dull, for we feel very old and have no amusement, and lead
a solitary life. But we intend in a few weeks to spend a few days in
London, and then if you have anything else to do in London, you would
perhaps come and lunch with us. (My father had the pleasure of seeing
Mrs. Haliburton at his brother's house in Queen Anne Street.)
Believe me, my dear Sarah, Yours gratefully and affectionately, CHARLES
DARWIN.
[The following letter was called forth by the publication of a volume
devoted to the criticism of the 'Power of Movement in Plants' by an
accomplished botanist, Dr. Julius Wiesner, Professor of Botany in the
University of Vienna:]
CHARLES DARWIN TO JULIUS WIESNER. Down, October 25th, 1881.
My dear Sir,
I have now finished your book ('Das Bewegungsvermogen der Pflanzen.'
Vienna, 1881.), and have understood the whole except a very few
passages. In the first place, let me thank you cordially for the manner
in which you have everywhere treated me. You have shown how a man may
differ from another in the most decided manner, and yet express his
difference with the most perfect courtesy. Not a few English and German
naturalists might learn a useful lesson from your example; for the
coarse language often used by scientific men towards each other does no
good, and only degrades science.
I have been profoundly interested by your book, and some of your
experiments are so beautiful, that I actually felt pleasure while being
vivisected. It would take up too much space to discuss all the important
topics in your book. I fear that you have quite upset the interpretation
which I have given of the effects of cutting off the tips of
horizontally extended roots, and of those laterally exposed to moisture;
but I cannot persuade myself that the horizontal position of lateral
branches and roots is due simply to their lessened power of growth. Nor
when I think of my experiments with the cotyledons of Phalaris, can I
give up the belief of the transmission of some stimulus due to light
from the upper to the lower part. At page 60 you have misunderstood my
meaning, when you say that I believe that the effects from light
are transmitted to a part which is not itself heliotropic. I never
considered whether or not the short part beneath the ground was
heliotropic; but I believe that with young seedlings the part which
bends NEAR, but ABOVE the ground is heliotropic, and I believe so from
this part bending only moderately when the light is oblique, and bending
rectangularly when the light is horizontal. Nevertheless the bending of
this lower part, as I conclude from my experiments with opaque caps,
is influenced by the action of light on the upper part. My opinion,
however, on the above and many other points, signifies very little, for
I have no doubt that your book will convince most botanists that I am
wrong in all the points on which we differ.
Independently of the question of transmission, my mind is so full of
facts leading me to believe that light, gravity, etc., act not in a
direct manner on growth, but as stimuli, that I am quite unable to
modify my judgment on this head. I could not understand the passage at
page 78, until I consulted my son George, who is a mathematician. He
supposes that your objection is founded on the diffused light from the
lamp illuminating both sides of the object, and not being reduced, with
increasing distance in the same ratio as the direct light; but he doubts
whether this NECESSARY correction will account for the very little
difference in the heliotropic curvature of the plants in the successive
pots.
With respect to the sensitiveness of the tips of roots to contact, I
cannot admit your view until it is proved that I am in error about bits
of card attached by liquid gum causing movement; whereas no movement
was caused if the card remained separated from the tip by a layer of the
liquid gum. The fact also of thicker and thinner bits of card attached
on opposite sides of the same root by shellac, causing movement in one
direction, has to be explained. You often speak of the tip having been
injured; but externally there was no sign of injury: and when the tip
was plainly injured, the extreme part became curved TOWARDS the injured
side. I can no more believe that the tip was injured by the bits of
card, at least when attached by gum-water, than that the glands of
Drosera are injured by a particle of thread or hair placed on it, or
that the human tongue [is so] when it feels any such object.
About the most important subject in my book, namely circumnutation, I
can only say that I feel utterly bewildered at the difference in our
conclusions; but I could not fully understand some parts which my
son Francis will be able to translate to me when he returns home. The
greater part of your book is beautifully clear.
Finally, I wish that I had enough strength and spirit to commence
a fresh set of experiments, and publish the results, with a full
recantation of my errors when convinced of them; but I am too old for
such an undertaking, nor do I suppose that I shall be able to do much,
or any more, original work. I imagine that I see one possible source of
error in your beautiful experiment of a plant rotating and exposed to a
lateral light.
With high respect and with sincere thanks for the kind manner in which
you have treated me and my mistakes, I remain, my dear Sir, yours
sincerely,
CHARLES DARWIN.