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We cannot follow in detail the profoundly suggestive chapters on Hybridism, on the Imperfection of the Geological Record, on the Geological Succession of Organic Beings, on the Geographical Distribution, and on the Mutual Affinity of Plants and Animals. The first of these is one of the most difficult portions of the subject, and yet remains as a stumbling-block of science by its apparently inexplicable phenomena. The author throws on the past history of life on the earth the glamour of a fairy record, as he contemplates the infinite number of generations, which the mind cannot grasp, which must have succeeded one another in the long roll of years, the limited extent to which at any time fossil remains have been preserved, the immense amount of destruction of such records which has taken place; and hence argues most powerfully how improbable it is that the transitional stages from species to species should have been handed down and also (another rare chance) have been laid open to us. The great array of facts about extinct animals and plants is shown to be consistent with, and to be largely explained by, descent with modification, and to be incomprehensible on any other view. The eccentric contrasts and parallelisms displayed in the geographical distribution of plants and animals, the striking effects of barriers such as mountains, deserts, and seas, the phenomena of dispersion of living creatures, the indications of old glacial periods in the present distribution of Alpine plants, the strange distribution of fresh-water animals and plants, the specialities of oceanic islands, and many other subjects of a like kind, are dealt with, all being turned to advantage, and shown to give strong support to Darwin’s view.

Classification and classifiers are all made to bear testimony in the same direction. Morphology, which, in the hands of Huxley, Haeckel, Gegenbaur, Ray Lankester, and Balfour has, since the first issue of the “Origin of Species,” grown into a coherent science, based on embryology, was even then seen by Darwin to yield evidence for his views. Examining very young animals, he found that in very distinct races of dogs and horses the young had by no means acquired their adult differences. He compared pigeons of extremely various breeds twelve hours after being hatched, and found their differences incomparably less than in the full-grown birds. How immensely morphological science has progressed since Darwin directed investigation into this profitable line would need a separate treatise to show; but it is not too much to say that embryology alone, without other evidence, would now suffice to prove the doctrine of descent with adaptive modification.

Rudimentary organs, again, strange appearances, like the presence of teeth in unborn whales and in the front of the upper jaws of unborn calves, the rudimentary wings of many insects, the rudimentary stamens or pistils of many flowers, are all swept into the Darwinian net. “Nothing can be plainer than that wings are formed for flight; yet in how many insects do we see wings so reduced in size as to be utterly incapable of flight, and not rarely lying under wing-cases, firmly soldered together?” These phenomena are all explicable if descent with modification is true.

Approaching the close of his work, the author expressed his doubts of being able to convert naturalists of long standing to his views; but based his main hopes on young and rising men approaching these questions without prejudices. He put some puzzling questions, however, to those who might oppose him. Did they really believe that at innumerable periods in the earth’s history certain atoms had been commanded suddenly to flash into living tissues? Were animals and plants created as eggs or seed or as full grown? At each act of creation was one individual or were many produced? For himself, he came to the conclusion that all organic beings had descended from some one primordial form into which life was first breathed.

On this view Darwin predicted that a great increase of interest in many departments of natural history would arise. “When we no longer look at an organic being as a savage looks at a ship, as at something wholly beyond his comprehension; when we regard every production of nature as one which has had a history; when we contemplate every complex structure and instinct as the summing up of many contrivances, each useful to the possessor, nearly in the same way as when we look at any great mechanical invention as the summing up of the labour, the experience, the reason, and even the blunders of numerous workmen; when we thus view each organic being, how far more interesting – I speak from experience – will the study of natural history become… The whole history of the world, as at present known, although of a length quite incomprehensible to us, will hereafter be recognized as a mere fragment of time compared with the ages which have elapsed since the first creature, the progenitor of innumerable extinct and living descendants, was created… We may look forward with some confidence to a secure future of equally inappreciable length. And as natural selection works solely by and for the good of each being, all corporeal and mental endowments will tend to progress towards perfection.” The concluding sentence of the “Origin of Species” has become one of our classical quotations. “There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.”

This is not the place to give a history of the criticisms and discussions which arose in regard to “The Origin of Species,” especially as Darwin himself took no public part in them, except by the alterations made in successive editions. As indicating the tone of prominent critical organs, we may note that The Athenæum (November 19, 1859) acknowledges there is something poetical in the theory. “If a monkey has become a man, what may not a man become?” Neither book, author, nor subject being ordinary, “the work deserves attention.” The Edinburgh Review considered that the author left the question very nearly where he found it. Failing to find original observations adequate even to give a colour to the hypothesis, the reviewer sought to find flaws in the author’s mode of reasoning, and concluded that “we are called upon to accept a hypothesis on the plea of want of knowledge.” Defective information, vagueness, and incompleteness are charged upon the man whom we now delight to honour; “intellectual husks,” we are told; are all that he offers. Professor Huxley, who lectured at the Royal Institution, on February 10, 1860, on “Species and Races and their Origin,” and brought forward Darwin’s investigations as exemplifying that application of science to which England owes her greatness, was told that it more truly paralleled “the abuse of science to which a neighbouring nation – some seventy years since – owed its temporary degradation.” And the professor was accused of audaciously seeking to blind his audience. Samuel Wilberforce, then Bishop of Oxford, was equally denunciatory in The Quarterly. He hopes that “this flimsy speculation” will be completely put down. “It is a dishonouring view of nature… Under such influences,” says the courtly bishop, “a man soon goes back to the marvelling stare of childhood at the centaurs and hippogriffs of fancy; or, if he is of a philosophic turn, he comes, like Oken, to write a scheme of creation under a ‘sort of inspiration,’ but it is the frenzied inspiration of the inhaler of mephitic gas. The whole world of nature is laid for such a man under a fantastic law of glamour, and he becomes capable of believing anything; and he is able, with a continually growing neglect of all the facts around him, with equal confidence and equal delusion, to look back to any past and to look on to any future.”¹¹

The Saturday Review was much more moderate, by no means sharing the anxiety of those who regarded evolutionary theories as hostile to Christianity. The author is said to have encountered the difficulties of his theory “with admirable skill and ability,” and though The Saturday remained unconvinced of his general argument, yet it acknowledged itself “persuaded that natural selection must henceforward be admitted as the chief mode by which the structure of organised beings is modified in a state of nature;” and thought it very possible that, through its agency, considerable groups of nearly allied species might have been derived from a single progenitor: but there The Saturday stopped, believing in limits to this power.

The second edition of “The Origin of Species,” which appeared in January, 1860, only six weeks after the first, contained but few alterations; the third, in March, 1861, had received extensive additions and corrections. The most important of these discussed the so-called tendency of organisation to advance, and explained the present coexistence of high and lowly organised forms. A valuable historical sketch of the modern progress of opinion on the subject, from Lamarck’s time, was prefixed to the book. It was further enlarged in subsequent editions, as evidences accumulated that various thinkers had independently adopted the evolution theory, or the more special one of natural selection. Notable instances of anticipation were those of Dr. Wells, who, in a paper read before the Royal Society in 1813, but not published till 1818, had expressed the opinion that all animals tend to vary; that agriculturists improve breeds by selection; and that what they do by art “seems to be done with equal efficacy, though more slowly, by nature, in the formation of varieties of mankind.” He then goes on to exemplify the survival of the fittest, though in other words. Mr. Patrick Matthew, in 1831, published a work on “Naval Timber and Arboriculture,” in which he expressed, in scattered passages, a view nearly resembling Darwin’s.

The fourth edition of “The Origin,” in 1866, was longer, by fifty pages, than its predecessor. Among the additions may be mentioned a fuller treatment of the argument from embryology, which was made stronger by later investigations. The fifth edition (1869) was comparatively little increased in bulk, though altered in many details. In particular it contained a somewhat important change relating to the extent of the influence of natural selection. This is also referred to in “The Descent of Man” (first edition, vol. i. pp. 152-3), where the author says he had not formerly considered sufficiently the existence of many structures which appeared to be neither beneficial nor injurious, and had attributed too much to natural selection. “I was not able,” he says, “to annul the influence of my former belief, then widely prevalent, that each species had been purposely created; and this led to my tacitly assuming that every detail of structure, excepting rudiments, was of some special, though unrecognised, service… If I have erred in giving to natural selection great power, which I am far from admitting, or in having exaggerated its power, which is in itself probable, I have, at least, as I hope, done good service in aiding to overthrow the dogma of separate creations.”

The sixth edition (1872), in smaller type, was considerably revised and altered, and remains permanent. A glossary of scientific terms was added by Mr. W. S. Dallas. A new chapter was inserted after the sixth, and entitled “Miscellaneous Objections to the Theory of Natural Selection.” It was partly derived from modified portions of chapter iv. of former editions, but the latter and larger part was new, and relates chiefly to the supposed incompetency of natural selection to account for the very early stages of useful structures. Numerous cases, such as the development of the giraffe’s neck, the baleen of the whale, the mammary glands, &c., are admirably discussed. Causes preventing the acquisition, through natural selection, of useful structures in many cases are dealt with, and reasons given for disbelieving in great and sudden modifications. In the concluding chapter Darwin further admits that he had formerly underrated the frequency and importance of use and disuse of parts, of the direct action of external conditions, and of variations which seem to us, in our ignorance, to arise spontaneously. He alludes to misrepresentations of his views, and calls attention to the fact that, in the first edition, at the close of the introduction, he stated his conviction that natural selection had been the main, but not the exclusive means of modification. “This has been of no avail. Great is the power of steady misrepresentation; but the history of science shows that, fortunately, this power does not long endure.” This is Darwin’s almost sole allusion in his works to the persistence with which views not his had been attributed to him, or he had been calumniated for views he did hold. But in his own lifetime – nay, within fifteen years – he witnessed a sufficiently satisfying revolution. “I formerly spoke to very many naturalists on the subject of evolution, and never once met with any sympathetic agreement. It is probable that some did then believe in evolution, but they were either silent or expressed themselves so ambiguously, that it was not easy to understand their meaning. Now things are wholly changed, and almost every naturalist admits the great principle of evolution” (“Origin,” sixth edition, p. 424). At present the sale of the book in this country approaches forty thousand copies. Its sale in America has been very large; and numerous translations into German, French, Italian, Russian, Dutch, and Swedish, and even into Japanese and Hindustani, have been largely sold. It must always be one of the most valued of all English classics.

CHAPTER VI

WE have already gathered much concerning Darwin’s mental and moral fibre in our survey of his works. Let us make some further acquaintance with his personality as known to his friends. Outwardly he appeared a man of powerful physique, standing six feet high, with prominent forehead and over-arching brow, and keen, deep-set eyes in which resolute strength and piercing insight were indicated. Apart from his persistent infirmity, he was actively disposed, as indeed is evident from the laborious journeys he undertook during his travels. Field sports, including hunting, were among the recreations of his more active years. But through all his work or recreation the imperious conditions necessitated by his infirmity of stomach had to be considered, and nothing but the most rigorous care could possibly have enabled him to achieve what he did. On many days he could not work at all, and on many others two or three hours were his limit. And what but his own system, his own orderliness and perseverance could have accomplished his task? In preparing his books he had a special set of shelves for each, standing on or near his writing-table, one shelf for each chapter. The maxim, “Early to bed, and early to rise,” was his essentially, and regularity kept all balanced. Rising at six, he took a cold plunge bath, breakfasted simply, and took a first walk, beginning work often at eight. “Later in the day,” I quote from Mr. Woodall’s pleasant pages, “he generally walked again, often in his own grounds, but sometimes further afield, and then generally by quiet footpaths rather than frequented roads. The walks at one time were varied by rides along the lanes on a favourite black cob, but some years before his death his four-footed friend fell, and died by the roadside, and from that day the habit of riding was given up. Part of the evening was devoted to his family and his friends, who delighted to gather round him to enjoy the charm of his bright intelligence, and his unrivalled stores of knowledge. To Down, occasionally, came distinguished men from many lands; and there in later years would sometimes be found the younger generation of scientific students, looking up to the great naturalist with the reverence of disciples, who had experienced his singular modesty, his patient readiness to listen to all opinions, and the winning grace with which he informed their ignorance and corrected their mistakes. In the midst of all the delights of home and the demands of study, Darwin kept an open mind for public affairs. He united the earnest politician with the patient student: a rare combination, which supplies another proof of his largeness of heart and sympathy with his fellow men. In the village of Down he was liked by everybody, old and young, and in his own household the same servants lived year after year under his roof. One of them, Margaret Evans, who assisted in nursing him in his last illness, had come to Down nearly forty years before, from Shrewsbury, where her uncle and aunt were in Dr. Darwin’s service.”

At Down the family in time numbered nine children, two, however, not surviving childhood; one died in 1842, another in 1858. His five sons have already attained distinction or positions of influence. The eldest, William Erasmus, became a banker in Southampton; the second, George, was second Wrangler and Smith’s Prizeman at Cambridge in 1868, became a Fellow of Trinity, and is now Plumian Professor of Astronomy at his university, having early gained the Fellowship of the Royal Society for his original papers bearing on the evolution of the universe and the solar system, and many other subjects of high mathematical and philosophical interest. His third son, Francis, gained first-class honours in the Cambridge Natural Science Tripos in 1870, and is likewise a Fellow of the Royal Society, in recognition of his original botanical investigations. The fourth, Leonard, an officer in the Royal Engineers, has done valuable astronomical work. The fifth, Horace, has devoted himself to mechanical science, and has largely aided in developing the Cambridge Scientific Instrument Company.

The great thinker, fulfilling his duties as head of a family with singular success, charged with the burden of new thoughts and observations, slowly perfecting his life work, had neither time nor inclination for controversy. He set himself to publish facts, which by their accumulation tended to clench his arguments. Soon after the “Origin of Species” he had in course of publication several important botanical papers, on the two forms of flower in the Primrose genus (1862), and in the genus Linum (flax), 1863, on the forms of Loosestrife, 1864, all published in the Linnean Society’s Journal.

In 1862 he brought out his first botanical book, the “Fertilisation of Orchids,” more fully entitled, “On the various Contrivances by which Orchids are Fertilised by Insects.” These most singular flowers had long attracted great attention owing to their peculiar shapes and often their great beauty, while their marked deviation from typical forms of flowers perplexed botanists extremely. The celebrated Robert Brown, in a well-known paper in the Linnean Society’s Transactions, 1833, expressed the belief that insects are necessary for the fructification of most orchids; and as far back as 1793, Christian Sprengel (in “The Newly Discovered Secret of Nature”) gave an excellent account of the action of the several parts in the genus Orchis, having discovered that insects were necessary to remove the pollen masses. But the rationale of the process was not fully known until Darwin revealed it, and illuminated it by the light of natural selection. He had, in the “Origin of Species,” given reasons for the belief that it is an almost universal law of nature that the higher organic beings require an occasional cross with another individual. He here emphasised that doctrine by a series of proofs from a peculiar and otherwise inexplicable order of plants, and showed that the arrangements by which orchids are fertilised have for their main object the fertilisation of the flowers with pollen brought by insects from a distinct plant.

In the group to which our common orchids belong, remarkable adaptations for securing that the pollen masses brought from another flower solely through the visits of insects shall reach their precise destination, were brought to light. “A poet,” says Darwin, “might imagine that whilst the pollinia were borne through the air from flower to flower, adhering to an insect’s body, they voluntarily and eagerly placed themselves in that exact position in which alone they could hope to gain their wish and perpetuate their race.” As he had examined all the British genera, Darwin’s conclusions were indubitable. He had patiently watched for hours on the grass to notice insects’ visits, had counted the fertilised flowers on many spikes, the fertilised spikes on many plants, had dissected and redissected the flowers till he saw how the fertilisation must absolutely be effected; and utilising the enthusiasm of orchid growers, had excited them to do the same, till his storehouse of facts was full.

On examining the exotic forms of orchids, which are so conspicuous in our conservatories, still more striking facts presented themselves. In the great group of the Vandeæ, relative position of parts, friction, viscidity, elastic and hygrometric movements were all found to be nicely related to one end – the aid of insects in fertilisation. Without their aid not a plant in the various species of twenty-nine genera which Darwin examined would set a seed. In the majority of cases insects withdraw the pollen masses only when retreating from the flower, and, continuing their flower visits, effect a union between two flowers, generally on distinct plants. In many cases the pollen masses slowly change their position while adhering to the insects, and so assume a proper direction for striking the stigma of another flower, and the insects during this interval will almost certainly have flown from one plant to another.

The family to which Catasetum belongs furnished the most remarkable examples. This plant possesses a special sensitiveness in certain parts, and when definite points of the flower are touched by an insect the pollen masses are shot forth like an arrow, the point being blunt and adhesive. The insect, disturbed by so sharp a blow, or having eaten its fill, flies sooner or later to a female plant, and whilst standing in the same position as before, the pollen-bearing end of the arrow is inserted into the stigmatic cavity, and a mass of pollen is left on its viscid surface. The strange structures of Cypripedium, or the Lady’s Slipper, were then analysed, and the mode of fertilisation by small bees was discovered. The whole structure of orchids, as modified to secure insects’ visits and cross fertilisation, was now expounded, and the benefits shown by cases where insects’ visits were prevented, and no seed was set. The number of seeds in a capsule was reckoned, and thence it was found that the progeny of a single plant of the common orchis would suffice to cover the globe in the fourth generation. A single plant of another orchid might bear seventy-four millions of seeds: surely an ample provision for a struggle for existence, and selection and survival of the fittest. But, as Darwin remarks, profuse expenditure is nothing unusual in nature, and it appears to be more profitable for a plant to yield a few cross-fertilised than many self-fertilised seeds.

Darwin impresses forcibly on his readers the endless diversity of structures, and the prodigality of resources displayed for gaining the same end, the fertilisation of one flower by pollen from another plant. “The more I study nature,” he says, “the more I become impressed with ever-increasing force that the contrivances and beautiful adaptations slowly acquired through each part occasionally varying in a slight degree … transcend in an incomparable manner the contrivances and adaptations which the most fertile imagination of man could invent.” Finally he concludes: “It is hardly an exaggeration to say that nature tells us, in the most emphatic manner, that she abhors perpetual self-fertilisation”; and thus was announced a new doctrine in botany. A second much-improved edition of this book appeared in 1877.

In 1864, in presenting the Copley medal of the Royal Society to the author of the “Origin of Species,” Major-General Sabine, the President, entered into a full description of the merits of his works, “stamped throughout with the impress of the closest attention to minute details and accuracy of observation, combined with large powers of generalisation.” The award, while highly eulogising the “Origin,” was not however based upon it, but on the more recent botanical writings. “The Fertilisation of Orchids” was described as perhaps the most masterly treatise on any branch of vegetable physiology that had ever appeared; and the fact was justly emphasised that all Darwin’s botanical discoveries had been obtained by the study of some of the most familiar and conspicuous of our native plants, and some of the best-known and easily-procured cultivated exotics.

In 1865 appeared another work from the Darwinian treasury, but in this case it was at first restricted to the Journal of the Linnean Society (vol. ix.), and was not made generally available till the second edition was published separately in 1875. “The Movements and Habits of Climbing Plants” described in the first place the twining of the hop plant, studied by night and day continuously, in a well-warmed room, to which the author was confined by illness. Again and again were different species of plants watched, and the periods in which their shoots revolved noted. The clematises, tropæolums, solanums, gloriosa lilies among leaf-climbing plants; the bignonias, cobæas, bryonies, vines, passion flowers, and other tendril-bearing plants; the ivy, and other root and hook climbers were carefully studied; and botanists for the first time realised fully the advantages which climbing plants possess in the struggle for existence. The climbing faculty depends on a sensitiveness to contact with any firm support, and a most interesting series of modifications has probably, as Darwin suggests, led to the present development of climbing organs, by the spontaneous movement of young shoots and other organs, and by unequal growth.

In concluding, the author made some most profoundly suggestive remarks, which went far to revolutionise our conception of plants. “It has often been vaguely asserted that plants are distinguished from animals by not having the power of movement. It should rather be said that plants acquire and display this power only when it is of some advantage to them; this being of comparatively rare occurrence, as they are affixed to the ground, and food is brought to them by the air and rain. We see how high in the scale of organisation a plant may rise, when we look at one of the more perfect tendril-bearers. It first places its tendrils ready for action, as a polypus places its tentacula. If the tendril be displaced, it is acted on by the force of gravity, and rights itself. It is acted on by the light, and bends towards or from it, or disregards it, which ever may be most advantageous. During several days the tendrils, or internodes, or both, spontaneously revolve with a steady motion. The tendril strikes some object, and quickly curls round and firmly grasps it. In the course of some hours it contracts into a spire, dragging up the stem, and forming an excellent spring. All movements now cease. By growth the tissues soon become wonderfully strong and durable. The tendril has done its work, and has done it in an admirable manner.”

The labour of revising the successive editions of the “Origin of Species,” together with prolonged ill-health, delayed the fulfilment of the promise given in that work, that the facts upon which it was based should be published. It was not till 1868 that the first instalment, “The Variation of Animals and Plants under Domestication,” was given to the world, in two large volumes, with numerous illustrations. The author’s design was to discuss in a second work the variability of organic beings in a state of nature, and the conversion of varieties into species, the struggle for existence and the operation of natural selection, and the principal objections to the theory, including questions of instinct and hybridisation. In a third work it was intended to test the principle of natural selection by the extent to which it explains the geological succession of organic beings, their distribution in past and present times, and their mutual affinities and homologies. The two latter works were never completed, in consequence of ill-health, and the labour involved in dealing with objections to and new facts in support of the “Origin,” and of the other works which at various times it became important to complete. But many portions of these subjects were admirably dealt with by disciples. In some cases Darwin’s views led to the rapid growth of a new science, such as that of comparative embryology, and it would not have been possible for him to cope with and interpret the multitude of new and astonishing facts discovered, which changed the face of organic nature as viewed by biologists. By doing each day the work which seemed most necessary, and which he could best do, Darwin managed, in spite of his infirmity of constitution, to complete a larger body of original work, both in experiment and in thought, together with a greater quantity of bibliographical study and collation of observed facts, than any Englishman perhaps has ever done.

The valuable book on “Variation” records and systematises a vast number of facts respecting all our principal domestic animals and cultivated plants. It gives evidence of wide reading, as well as great diligence in writing letters of inquiry to all living authorities who could give accurate information. Very many visits were paid to zoological gardens, breeders’ establishments, nursery grounds, &c.; and the preparation of skulls, skins, &c., was a frequent occurrence in the Darwinian laboratory. To take the case of rabbits alone, which occupied but a fraction of the time devoted to pigeons: over twenty works are quoted for historical facts, skeletons of various rabbits were prepared and exhaustively compared, the effects of use and disuse of parts traced, most careful measurements are given, and a list of the modifications which domestic rabbits have undergone, with the probable causes, concludes the chapter. As to pigeons, no pigeon-fancier ought to be without the book, for never assuredly was a sporting topic treated by so great a thinker and so admirably. The numerous experiments in crossing different breeds, and the results obtained, make this one of the most instructive books for all breeders. It would seem desirable that this portion of the book should be issued in a separate form. Again, when we turn to the sections on plants we see how indefatigable Darwin was, for he tells us that he cultivated fifty-four varieties of gooseberries alone, and compared them throughout in flower and fruit.