Dr. E. Krause[236 - Charles Darwin und sein Verhältniss zu Deutschland, 1885.] has given a good account of Professor Haeckel's services in the cause of Evolution. After speaking of the lukewarm reception which the Origin met with in Germany on its first publication, he goes on to describe the first adherents of the new faith as more or less popular writers, not especially likely to advance its acceptance with the professorial or purely scientific world. And he claims for Haeckel that it was his advocacy of Evolution in his Radiolaria (1862), and at the "Versammlung" of Naturalists at Stettin in 1863, that placed the Darwinian question for the first time publicly before the forum of German science, and his enthusiastic propagandism that chiefly contributed to its success.
Mr. Huxley, writing in 1869, paid a high tribute to Professor Haeckel as the Coryphæus of the Darwinian movement in Germany. Of his Generelle Morphologie, "an attempt to work out the practical applications" of the doctrine of Evolution to their final results, he says that it has the "force and suggestiveness, and … systematising power of Oken without his extravagance." Mr. Huxley also testifies to the value of Haeckel's Schöpfungs-Geschichte as an exposition of the Generelle Morphologie "for an educated public."
Again, in his Evolution in Biology,[237 - An article in the Encyclopædia Britannica, 9th edit., reprinted in Science and Culture, 1881, p. 298.] Mr. Huxley wrote: "Whatever hesitation may not unfrequently be felt by less daring minds, in following Haeckel in many of his speculations, his attempt to systematise the doctrine of Evolution and to exhibit its influence as the central thought of modern biology, cannot fail to have a far-reaching influence on the progress of science."
In the following letter my father alludes to the somewhat fierce manner in which Professor Haeckel fought the battle of 'Darwinismus,' and on this subject Dr. Krause has some good remarks (p. 162). He asks whether much that happened in the heat of the conflict might not well have been otherwise, and adds that Haeckel himself is the last man to deny this. Nevertheless he thinks that even these things may have worked well for the cause of Evolution, inasmuch as Haeckel "concentrated on himself by his Ursprung des Menschen-Geschlechts, his Generelle Morphologie, and Schöpfungs-Geschichte, all the hatred and bitterness which Evolution excited in certain quarters," so that, "in a surprisingly short time it became the fashion in Germany that Haeckel alone should be abused, while Darwin was held up as the ideal of forethought and moderation."
C. D. to E. Haeckel. Down, May 21, 1867
Dear Haeckel, – Your letter of the 18th has given me great pleasure, for you have received what I said in the most kind and cordial manner. You have in part taken what I said much stronger than I had intended. It never occurred to me for a moment to doubt that your work, with the whole subject so admirably and clearly arranged, as well as fortified by so many new facts and arguments, would not advance our common object in the highest degree. All that I think is that you will excite anger, and that anger so completely blinds every one that your arguments would have no chance of influencing those who are already opposed to our views. Moreover, I do not at all like that you, towards whom I feel so much friendship, should unnecessarily make enemies, and there is pain and vexation enough in the world without more being caused. But I repeat that I can feel no doubt that your work will greatly advance our subject, and I heartily wish it could be translated into English, for my own sake and that of others. With respect to what you say about my advancing too strongly objections against my own views, some of my English friends think that I have erred on this side; but truth compelled me to write what I did, and I am inclined to think it was good policy. The belief in the descent theory is slowly spreading in England,[238 - In October, 1867, he wrote to Mr. Wallace: – "Mr. Warrington has lately read an excellent and spirited abstract of the Origin before the Victoria Institute, and as this is a most orthodox body, he has gained the name of the Devil's Advocate. The discussion which followed during three consecutive meetings is very rich from the nonsense talked."] even amongst those who can give no reason for their belief. No body of men were at first so much opposed to my views as the members of the London Entomological Society, but now I am assured that, with the exception of two or three old men, all the members concur with me to a certain extent. It has been a great disappointment to me that I have never received your long letter written to me from the Canary Islands. I am rejoiced to hear that your tour, which seems to have been a most interesting one, has done your health much good.
… I am very glad to hear that there is some chance of your visiting England this autumn, and all in this house will be delighted to see you here.
Believe me, my dear Haeckel, yours very sincerely
I place here an extract from a letter of later date (Nov. 1868), which refers to one of Haeckel's later works.[239 - Die natürliche Schöpfungs-Geschichte, 1868. It was translated and published in 1876, under the title, The History of Creation.]
"Your chapters on the affinities and genealogy of the animal kingdom strike me as admirable and full of original thought. Your boldness, however, sometimes makes me tremble, but as Huxley remarked, some one must be bold enough to make a beginning in drawing up tables of descent. Although you fully admit the imperfection of the geological record, yet Huxley agreed with me in thinking that you are sometimes rather rash in venturing to say at what periods the several groups first appeared. I have this advantage over you, that I remember how wonderfully different any statement on this subject made 20 years ago, would have been to what would now be the case, and I expect the next 20 years will make quite as great a difference."
The following extract from a letter to Professor W. Preyer, a well-known physiologist, shows that he estimated at its true value the help he was to receive from the scientific workers of Germany: —
March 31, 1868.
… I am delighted to hear that you uphold the doctrine of the Modification of Species, and defend my views. The support which I receive from Germany is my chief ground for hoping that our views will ultimately prevail. To the present day I am continually abused or treated with contempt by writers of my own country; but the younger naturalists are almost all on my side, and sooner or later the public must follow those who make the subject their special study. The abuse and contempt of ignorant writers hurts me very little…
I must now pass on to the publication, in 1868, of his book on The Variation of Animals and Plants under Domestication. It was begun two days after the appearance of the second edition of the Origin, on Jan. 9, 1860, and it may, I think, be reckoned that about half of the eight years that elapsed between its commencement and completion was spent on it. The book did not escape adverse criticism: it was said, for instance, that the public had been patiently waiting for Mr. Darwin's pièces justicatives, and that after eight years of expectation, all they got was a mass of detail about pigeons, rabbits and silk-worms. But the true critics welcomed it as an expansion with unrivalled wealth of illustration of a section of the Origin. Variation under the influence of man was the only subject (except the question of man's origin) which he was able to deal with in detail so as to utilise his full stores of knowledge. When we remember how important for his argument is a knowledge of the action of artificial selection, we may well rejoice that this subject was chosen by him for amplification.
In 1864, he wrote to Sir Joseph Hooker:
"I have begun looking over my old MS., and it is as fresh as if I had never written it; parts are astonishingly dull, but yet worth printing, I think; and other parts strike me as very good. I am a complete millionaire in odd and curious little facts, and I have been really astounded at my own industry whilst reading my chapters on Inheritance and Selection. God knows when the book will ever be completed, for I find that I am very weak, and on my best days cannot do more than one or one and a half hours' work. It is a good deal harder than writing about my dear climbing plants."
In Aug. 1867, when Lyell was reading the proofs of the book, my father wrote: —
"I thank you cordially for your last two letters. The former one did me real good, for I had got so wearied with the subject that I could hardly bear to correct the proofs, and you gave me fresh heart. I remember thinking that when you came to the Pigeon chapter you would pass it over as quite unreadable. I have been particularly pleased that you have noticed Pangenesis. I do not know whether you ever had the feeling of having thought so much over a subject that you had lost all power of judging it. This is my case with Pangenesis (which is 26 or 27 years old), but I am inclined to think that if it be admitted as a probable hypothesis it will be a somewhat important step in Biology."
His theory of Pangenesis, by which he attempted to explain "how the characters of the parents are 'photographed' on the child, by means of material atoms derived from each cell in both parents, and developed in the child," has never met with much acceptance. Nevertheless, some of his contemporaries felt with him about it. Thus in February 1868, he wrote to Hooker: —
"I heard yesterday from Wallace, who says (excuse horrid vanity), 'I can hardly tell you how much I admire the chapter on Pangenesis. It is a positive comfort to me to have any feasible explanation of a difficulty that has always been haunting me, and I shall never be able to give it up till a better one supplies its place, and that I think hardly possible.' Now his foregoing [italicised] words express my sentiments exactly and fully: though perhaps I feel the relief extra strongly from having during many years vainly attempted to form some hypothesis. When you or Huxley say that a single cell of a plant, or the stump of an amputated limb, has the 'potentiality' of reproducing the whole – or 'diffuses an influence,' these words give me no positive idea; – but, when it is said that the cells of a plant, or stump, include atoms derived from every other cell of the whole organism and capable of development, I gain a distinct idea."
Immediately after the publication of the book, he wrote:
Down, February 10 [1868].
My dear Hooker, – What is the good of having a friend, if one may not boast to him? I heard yesterday that Murray has sold in a week the whole edition of 1500 copies of my book, and the sale so pressing that he has agreed with Clowes to get another edition in fourteen days! This has done me a world of good, for I had got into a sort of dogged hatred of my book. And now there has appeared a review in the Pall Mall which has pleased me excessively, more perhaps than is reasonable. I am quite content, and do not care how much I may be pitched into. If by any chance you should hear who wrote the article in the Pall Mall, do please tell me; it is some one who writes capitally, and who knows the subject. I went to luncheon on Sunday, to Lubbock's, partly in hopes of seeing you, and, be hanged to you, you were not there.
Your cock-a-hoop friend,
C. D.
Independently of the favourable tone of the able series of notices in the Pall Mall Gazette (Feb. 10, 15, 17, 1868), my father may well have been gratified by the following passages: —
"We must call attention to the rare and noble calmness with which he expounds his own views, undisturbed by the heats of polemical agitation which those views have excited, and persistently refusing to retort on his antagonists by ridicule, by indignation, or by contempt. Considering the amount of vituperation and insinuation which has come from the other side, this forbearance is supremely dignified."
And again in the third notice, Feb. 17: —
"Nowhere has the author a word that could wound the most sensitive self-love of an antagonist; nowhere does he, in text or note, expose the fallacies and mistakes of brother investigators … but while abstaining from impertinent censure, he is lavish in acknowledging the smallest debts he may owe; and his book will make many men happy."
I am indebted to Messrs. Smith and Elder for the information that these articles were written by Mr. G. H. Lewes.
The following extract from a letter (Feb. 1870) to his friend Professor Newton, the well-known ornithologist, shows how much he valued the appreciation of his colleagues.
"I suppose it would be universally held extremely wrong for a defendant to write to a Judge to express his satisfaction at a judgment in his favour; and yet I am going thus to act. I have just read what you have said in the 'Record'[240 - Zoological Record. The volume for 1868, published December, 1869.] about my pigeon chapters, and it has gratified me beyond measure. I have sometimes felt a little disappointed that the labour of so many years seemed to be almost thrown away, for you are the first man capable of forming a judgment (excepting partly Quatrefages), who seems to have thought anything of this part of my work. The amount of labour, correspondence, and care, which the subject cost me, is more than you could well suppose. I thought the article in the Athenæum was very unjust; but now I feel amply repaid, and I cordially thank you for your sympathy and too warm praise."
WORK ON MAN
In February 1867, when the manuscript of Animals and Plants had been sent to Messrs. Clowes to be printed, and before the proofs began to come in, he had an interval of spare time, and began a "Chapter on Man," but be soon found it growing under his hands, and determined to publish it separately as a "very small volume."
It is remarkable that only four years before this date, namely in 1864, he had given up hope of being able to work out this subject. He wrote to Mr. Wallace: —
"I have collected a few notes on man, but I do not suppose that I shall ever use them. Do you intend to follow out your views, and if so, would you like at some future time to have my few references and notes? I am sure I hardly know whether they are of any value, and they are at present in a state of chaos. There is much more that I should like to write, but I have not strength." But this was at a period of ill-health; not long before, in 1863, he had written in the same depressed tone about his future work generally: —
"I have been so steadily going downhill, I cannot help doubting whether I can ever crawl a little uphill again. Unless I can, enough to work a little, I hope my life may be very short, for to lie on a sofa all day and do nothing but give trouble to the best and kindest of wives and good dear children is dreadful."
The "Chapter on Man," which afterwards grew into the Descent of Man, was interrupted by the necessity of correcting the proofs of Animals and Plants, and by some botanical work, but was resumed with unremitting industry on the first available day in the following year. He could not rest, and he recognised with regret the gradual change in his mind that rendered continuous work more and more necessary to him as he grew older. This is expressed in a letter to Sir J. D. Hooker, June 17, 1868, which repeats to some extent what is given in the Autobiography: —
"I am glad you were at the Messiah, it is the one thing that I should like to hear again, but I dare say I should find my soul too dried up to appreciate it as in old days; and then I should feel very flat, for it is a horrid bore to feel as I constantly do, that I am a withered leaf for every subject except Science. It sometimes makes me hate Science, though God knows I ought to be thankful for such a perennial interest, which makes me forget for some hours every day my accursed stomach."
The Descent of Man (and this is indicated on its title-page) consists of two separate books, namely on the pedigree of mankind, and on sexual selection in the animal kingdom generally. In studying this latter part of the subject he had to take into consideration the whole subject of colour. I give the two following characteristic letters, in which the reader is as it were present at the birth of a theory.
C. D. to A. R. Wallace. Down, February 23 [1867]
Dear Wallace, – I much regretted that I was unable to call on you, but after Monday I was unable even to leave the house. On Monday evening I called on Bates, and put a difficulty before him, which he could not answer, and, as on some former similar occasion, his first suggestion was, "You had better ask Wallace." My difficulty is, why are caterpillars sometimes so beautifully and artistically coloured? Seeing that many are coloured to escape danger, I can hardly attribute their bright colour in other cases to mere physical conditions. Bates says the most gaudy caterpillar he ever saw in Amazonia (of a sphinx) was conspicuous at the distance of yards, from its black and red colours, whilst feeding on large green leaves. If any one objected to male butterflies having been made beautiful by sexual selection, and asked why should they not have been made beautiful as well as their caterpillars, what would you answer? I could not answer, but should maintain my ground. Will you think over this, and some time, either by letter or when we meet, tell me what you think?..
He seems to have received an explanation by return of post, for a day or two afterwards he could write to Wallace: —
"Bates was quite right; you are the man to apply to in a difficulty. I never heard anything more ingenious than your suggestion, and I hope you may be able to prove it true. That is a splendid fact about the white moths; it warms one's very blood to see a theory thus almost proved to be true."
Mr. Wallace's suggestion was that conspicuous caterpillars or perfect insects (e. g. white butterflies), which are distasteful to birds, benefit by being promptly recognised and therefore easily avoided.[241 - Mr. Jenner Weir's observations published in the Transactions of the Entomological Society (1869 and 1870) give strong support to the theory in question.]
The letter from Darwin to Wallace goes on: "The reason of my being so much interested just at present about sexual selection is, that I have almost resolved to publish a little essay on the origin of Mankind, and I still strongly think (though I failed to convince you, and this, to me, is the heaviest blow possible) that sexual selection has been the main agent in forming the races of man.
"By the way, there is another subject which I shall introduce in my essay, namely, expression of countenance. Now, do you happen to know by any odd chance a very good-natured and acute observer in the Malay Archipelago, who you think would make a few easy observations for me on the expression of the Malays when excited by various emotions?"
The reference to the subject of expression in the above letter is explained by the fact, that my father's original intention was to give his essay on this subject as a chapter in the Descent of Man, which in its turn grew, as we have seen, out of a proposed chapter in Animals and Plants.
He got much valuable help from Dr. Günther, of the Natural History Museum, to whom he wrote in May 1870: —
"As I crawl on with the successive classes I am astonished to find how similar the rules are about the nuptial or 'wedding dress' of all animals. The subject has begun to interest me in an extraordinary degree; but I must try not to fall into my common error of being too speculative. But a drunkard might as well say he would drink a little and not too much! My essay, as far as fishes, batrachians and reptiles are concerned, will be in fact yours, only written by me."