(286/3. We owe to Professor Judd the following interesting recollections of Mr. Darwin, written about 1883:--
"On this last occasion, when I congratulated him on his seeming better condition of health, he told me of the cause for anxiety which he had in the state of his heart. Indeed, I cannot help feeling that he had a kind of presentiment that his end was approaching. When I left him, he insisted on conducting me to the door, and there was that in his tone and manner which seemed to convey to me the sad intelligence that it was not merely a temporary farewell, though he himself was perfectly cheerful and happy.
"It is impossible for me adequately to express the impression made upon my mind by my various conversations with Mr. Darwin. His extreme modesty led him to form the lowest estimate of his own labours, and a correspondingly extravagant idea of the value of the work done by others. His deference to the arguments and suggestions of men greatly his juniors, and his unaffected sympathy in their pursuits, was most marked and characteristic; indeed, he, the great master of science, used to speak, and I am sure felt, as though he were appealing to superior authority for information in all his conversations. It was only when a question was fully discussed with him that one became conscious of the fund of information he could bring to its elucidation, and the breadth of thought with which he had grasped it. Of his gentle, loving nature, of which I had so many proofs, I need not write; no one could be with him, even for a few minutes, without being deeply impressed by his grateful kindliness and goodness.")
LETTER 287. TO COUNT SAPORTA. Down, August 15th, 1878.
I thank you very sincerely for your kind and interesting letter. It would be false in me to pretend that I care very much about my election to the Inst.i.tute, but the sympathy of some few of my friends has gratified me deeply.
I am extremely glad to hear that you are going to publish a work on the more ancient fossil plants; and I thank you beforehand for the volume which you kindly say that you will send me. I earnestly hope that you will give, at least incidentally, the results at which you have arrived with respect to the more recent Tertiary plants; for the close gradation of such forms seems to me a fact of paramount importance for the principle of evolution. Your cases are like those on the gradation in the genus Equus, recently discovered by Marsh in North America.
LETTER 288. TO THE DUKE OF ARGYLL.
(288/1. The following letter was published in "Nature," March 5th, 1891, Volume XLIII., page 415, together with a note from the late Duke of Argyll, in which he stated that the letter had been written to him by Mr. Darwin in reply to the question, "why it was that he did a.s.sume the unity of mankind as descended from a single pair." The Duke added that in the reply Mr. Darwin "does not repudiate this interpretation of his theory, but simply proceeds to explain and to defend the doctrine." On a former occasion the Duke of Argyll had "alluded as a fact to the circ.u.mstance that Charles Darwin a.s.sumed mankind to have arisen at one place, and therefore in a single pair." The letter from Darwin was published in answer to some scientific friends, who doubted the fact and asked for the reference on which the statement was based.)
Down, September 23rd, 1878.
The problem which you state so clearly is a very interesting one, on which I have often speculated. As far as I can judge, the improbability is extreme that the same well-characterised species should be produced in two distinct countries, or at two distinct times. It is certain that the same variation may arise in two distinct places, as with albinism or with the nectarine on peach-trees. But the evidence seems to me overwhelming that a well-marked species is the product, not of a single or of a few variations, but of a long series of modifications, each modification resulting chiefly from adaptation to infinitely complex conditions (including the inhabitants of the same country), with more or less inheritance of all the preceding modifications. Moreover, as variability depends more on the nature of the organism than on that of the environment, the variations will tend to differ at each successive stage of descent. Now it seems to me improbable in the highest degree that a species should ever have been exposed in two places to infinitely complex relations of exactly the same nature during a long series of modifications. An ill.u.s.tration will perhaps make what I have said clearer, though it applies only to the less important factors of inheritance and variability, and not to adaptation--viz., the improbability of two men being born in two countries identical in body and mind. If, however, it be a.s.sumed that a species at each successive stage of its modification was surrounded in two distinct countries or times, by exactly the same a.s.semblage of plants and animals, and by the same physical conditions, then I can see no theoretical difficulty [in]
such a species giving birth to the new form in the two countries. If you will look to the sixth edition of my "Origin," at page 100, you will find a somewhat a.n.a.logous discussion, perhaps more intelligible than this letter.
LETTER 289. W.T. THISELTON-DYER TO THE EDITOR OF "NATURE."
(289/1. The following letter ("Nature," Volume XLIII., page 535) criticises the interpretation given by the Duke to Mr. Darwin"s letter.)
Royal Gardens, Kew, March 27th [1891].
In "Nature" of March 5th (page 415), the Duke of Argyll has printed a very interesting letter of Mr. Darwin"s, from which he drew the inference that the writer "a.s.sumed mankind to have arisen...in a single pair." I do not think myself that the letter bears this interpretation.
But the point in its most general aspect is a very important one, and is often found to present some difficulty to students of Mr. Darwin"s writings.
Quite recently I have found by accident, amongst the papers of the late Mr. Bentham at Kew, a letter of friendly criticism from Mr. Darwin upon the presidential address which Mr. Bentham delivered to the Linnean Society on May 24th, 1869. This letter, I think, has been overlooked and not published previously. In it Mr. Darwin expresses himself with regard to the multiple origin of races and some other points in very explicit language. Prof. Meldola, to whom I mentioned in conversation the existence of the letter, urged me strongly to print it. This, therefore, I now do, with the addition of a few explanatory notes.
LETTER 290. TO G. BENTHAM. Down, November 25th, 1869.
(290/1. The notes to this letter are by Sir W. Thiselton-Dyer, and appeared in "Nature," loc. cit.)
I was greatly interested by your address, which I have now read thrice, and which I believe will have much influence on all who read it. But you are mistaken in thinking that I ever said you were wrong on any point.
All that I meant was that on certain points, and these very doubtful points, I was inclined to differ from you. And now, on further considering the point on which some two or three months ago I felt most inclined to differ--viz., on isolation--I find I differ very little.
What I have to say is really not worth saying, but as I should be very sorry not to do whatever you asked, I will scribble down the slightly dissentient thoughts which have occurred to me. It would be an endless job to specify the points in which you have interested me; but I may just mention the relation of the extreme western flora of Europe (some such very vague thoughts have crossed my mind, relating to the Glacial period) with South Africa, and your remarks on the contrast of pa.s.sive and active distribution.
Page lxx.--I think the contingency of a rising island, not as yet fully stocked with plants, ought always to be kept in mind when speaking of colonisation.
Page lxxiv.--I have met with nothing which makes me in the least doubt that large genera present a greater number of varieties relatively to their size than do small genera. (290/2. Bentham thought "degree of variability... like other const.i.tutional characters, in the first place an individual one, which...may become more or less hereditary, and therefore specific; and thence, but in a very faint degree, generic."
He seems to mean to argue against the conclusion which Sir Joseph Hooker had quoted from Mr. Darwin that "species of large genera are more variable than those of small." [On large genera varying, see Letter 53.]) Hooker was convinced by my data, never as yet published in full, only abstracted in the "Origin."
Page lxxviii.--I dispute whether a new race or species is necessarily, or even generally, descended from a single or pair of parents. The whole body of individuals, I believe, become altered together--like our race-horses, and like all domestic breeds which are changed through "unconscious selection" by man. (290/3. Bentham had said: "We must also admit that every race has probably been the offspring of one parent or pair of parents, and consequently originated in one spot." The Duke of Argyll inverts the proposition.)
When such great lengths of time are considered as are necessary to change a specific form, I greatly doubt whether more or less rapid powers of multiplication have more than the most insignificant weight.
These powers, I think, are related to greater or less destruction in early life.
Page lxxix.--I still think you rather underrate the importance of isolation. I have come to think it very important from various grounds; the anomalous and quasi-extinct forms on islands, etc., etc., etc.
With respect to areas with numerous "individually durable" forms, can it be said that they generally present a "broken" surface with "impa.s.sable barriers"? This, no doubt, is true in certain cases, as Teneriffe. But does this hold with South-West Australia or the Cape? I much doubt.
I have been accustomed to look at the cause of so many forms as being partly an arid or dry climate (as De Candolle insists) which indirectly leads to diversified [?] conditions; and, secondly, to isolation from the rest of the world during a very long period, so that other more dominant forms have not entered, and there has been ample time for much specification and adaptation of character.
Page lx.x.x.--I suppose you think that the Restiaceae, Proteaceae (290/4.
It is doubtful whether Bentham did think so. In his 1870 address he says: "I cannot resist the opinion that all presumptive evidence is against European Proteaceae, and that all direct evidence in their favour has broken down upon cross-examination."), etc., etc., once extended over the world, leaving fragments in the south.
You in several places speak of distribution of plants as if exclusively governed by soil and climate. I know that you do not mean this, but I regret whenever a chance is omitted of pointing out that the struggle with other plants (and hostile animals) is far more important.
I told you that I had nothing worth saying, but I have given you my THOUGHTS.
How detestable are the Roman numerals! why should not the President"s addresses, which are often, and I am sure in this case, worth more than all the rest of the number, be paged with Christian figures?
LETTER 291. TO R. MELDOLA.
(291/1. "This letter was in reply to a suggestion that in his preface Mr. Darwin should point out by references to "The Origin of Species"
and his other writings how far he had already traced out the path which Weismann went over. The suggestion was made because in a great many of the continental writings upon the theory of descent, many of the points which had been clearly foreshadowed, and in some cases even explicitly stated by Darwin, had been rediscovered and published as though original. In the notes to my edition of Weismann I have endeavoured to do Darwin full justice.--R.M." See Letter 310.)
4, Bryanston Street, November 26th, 1878.
I am very sorry to say that I cannot agree to your suggestion. An author is never a fit judge of his own work, and I should dislike extremely pointing out when and how Weismann"s conclusions and work agreed with my own. I feel sure that I ought not to do this, and it would be to me an intolerable task. Nor does it seem to me the proper office of the preface, which is to show what the book contains, and that the contents appear to me valuable. But I can see no objection for you, if you think fit, to write an introduction with remarks or criticisms of any kind. Of course, I would be glad to advise you on any point as far as lay in my power, but as a whole I could have nothing to do with it, on the grounds above specified, that an author cannot and ought not to attempt to judge his own works, or compare them with others. I am sorry to refuse to do anything which you wish.
LETTER 292. TO T.H. HUXLEY. Down, January 18th, 1879.
I have just finished your present of the Life of Hume (292/1. "Hume" in Mr. Morley"s "English Men of Letters" series. Of the biographical part of this book Mr. Huxley wrote, in a letter to Mr. Skelton, January 1879 ("Life of T.H. Huxley," II., page 7): "It is the nearest approach to a work of fiction of which I have yet been guilty."), and must thank you for the great pleasure which it has given me. Your discussions are, as it seems to me, clear to a quite marvellous degree, and many of the little interspersed flashes of wit are delightful. I particularly enjoyed the pithy judgment in about five words on Comte. (292/2.
Possibly the pa.s.sage referred to is on page 52.) Notwithstanding the clearness of every sentence, the subjects are in part so difficult that I found them stiff reading. I fear, therefore, that it will be too stiff for the general public; but I heartily hope that this will prove to be a mistake, and in this case the intelligence of the public will be greatly exalted in my eyes. The writing of this book must have been awfully hard work, I should think.
LETTER 293. TO F. MULLER. Down, March 4th [1879].
I thank you cordially for your letter. Your facts and discussion on the loss of the hairs on the legs of the caddis-flies seem to me the most important and interesting thing which I have read for a very long time.
I hope that you will not disapprove, but I have sent your letter to "Nature" (293/1. Fritz Muller, "On a Frog having Eggs on its Back--On the Abortion of the Hairs on the Legs of certain Caddis-Flies, etc.": Muller"s letter and one from Charles Darwin were published in "Nature,"
Volume XIX., page 462, 1879.), with a few prefatory remarks, pointing out to the general reader the importance of your view, and stating that I have been puzzled for many years on this very point. If, as I am inclined to believe, your view can be widely extended, it will be a capital gain to the doctrine of evolution. I see by your various papers that you are working away energetically, and, wherever you look, you seem to discover something quite new and extremely interesting. Your brother also continues to do fine work on the fertilisation of flowers and allied subjects.
I have little or nothing to tell you about myself. I go slowly crawling on with my present subject--the various and complicated movements of plants. I have not been very well of late, and am tired to-day, so will write no more. With the most cordial sympathy in all your work, etc.
LETTER 294. TO T.H. HUXLEY. Down, April 19th, 1879.
Many thanks for the book. (294/1. Ernst Hackel"s "Freedom in Science and Teaching," with a prefatory note by T.H. Huxley, 1879. Professor Hackel has recently published (without permission) a letter in which Mr. Darwin comments severely on Virchow. It is difficult to say which would have pained Mr. Darwin more--the affront to a colleague, or the breach of confidence in a friend.) I have read only the preface...It is capital, and I enjoyed the tremendous rap on the knuckles which you gave Virchow at the close. What a pleasure it must be to write as you can do!