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Life of Charles Darwin
The large island of Chiloe was visited in November, and its climate even in summer proved wretched, reminding one of some parts of the Hebrides, a week without torrents of rain being wonderful. Castro, the almost deserted Spanish capital, could not furnish, even among hundreds of inhabitants, a pound of sugar or an ordinary knife. No one possessed either a watch or a clock, and the church bell was rung by guess by an old man who was supposed to have the best notion of time.
In December the rugged Chonos Archipelago, still further south, was explored. Here a storm worthy of Tierra del Fuego was experienced. “White, massive clouds were piled up against a dark blue sky, and across them black, ragged sheets of vapour were rapidly driven. The successive mountain ranges appeared like dim shadows; and the setting sun cast on the woodland a yellow gleam, much like that produced by the flame of spirits of wine on a man’s countenance. The water was white with the flying spray; and the wind lulled and roared again through the rigging. It was a most ominous, sublime scene.” While near Tres Montes the year 1835 was ushered in, as Darwin says, “with the ceremonies proper to it in these regions. She lays out no false hopes; a heavy N.W. gale, with steady rain, bespeaks the rising year. Thank God, we are not destined here to see the end of it, but hope then to be in the Pacific, where a blue sky tells one there is a heaven – a something beyond the sky above our heads.”
Valdivia being reached in February, the Beagle party were witnesses of a severe earthquake. Darwin was on shore, lying down in the wood to rest. The effect produced upon him by the motion he experienced was very marked: “There was no difficulty in standing upright, but the motion made me almost giddy. It was something like the movement of a vessel in a little cross ripple, or still more like that felt by a person skating over thin ice, which bends under the weight of his body. A bad earthquake at once destroys the oldest associations; the world, the very emblem of all that is solid, has moved beneath our feet like a crust over a fluid; one second of time has conveyed to the mind a strange idea of insecurity, which hours of reflection would never have created.” By the same earthquake every house in Concepcion (afterwards visited) was thrown down, and a most impressive sight met the travellers.
Arriving at Valparaiso again on March 11, 1835, after only an interval of two days the indefatigable explorer started to cross the Cordillera by the seldom traversed Portillo pass. Here geological observations were abundant. The roar of the mountain torrents spoke eloquently to the geologist. “The thousands and thousands of stones, which, striking against each other, make the one dull uniform sound, are all hurrying in one direction. It is like thinking of time, when the minute that now glides past is irrecoverable. So it is with these stones; the ocean is their eternity, and each note of that wild music tells of one other step towards their destiny.” Who can fail to discern in such a passage the poetic instinct which Erasmus Darwin more fully manifested?
Mendoza was reached on March 27th, and on the 29th the return journey by the northern or Uspallata pass was commenced. On the 10th of April Santiago was again arrived at, and Mr. Caldcleugh most hospitably welcomed the traveller, delighted with his expedition. “Never,” he says, “did I more deeply enjoy an equal space of time.” Various excursions in Northern Chili and Peru followed. Little was seen of Peru, owing to the troubled state of public affairs, and there was very little regret when the Beagle started early in September on her journey across the Pacific.
The Galapagos Islands, with their two thousand volcanic craters, their apparently leafless bushes and wretched weeds, their peculiar animals, so unsuspicious of man that they did not move when stones were thrown, were extremely interesting to the naturalist, and gave rise to numerous observations and suggestions in later works. The huge tortoises slowly carrying their great bodies about, appeared like strange antediluvian animals. The hideous large water-lizard (Amblyrhynchus), swimming with perfect ease, and capable of an hour’s immersion in sea-water; and the land lizard of the same genus, so numerous that at James Island it was hardly possible to find a spot free from their burrows, the roofs of which constantly give way under the pedestrian, were equally strange denizens of this group of islands, where reptiles replace herbivorous mammals. With regard to the last-mentioned species we find a remark indicating the persistence of a belief in special creation up to this date. “It would appear as if this species had been created in the centre of the Archipelago, and thence had been dispersed only to a certain distance.”
During the years intervening between the first and second editions of the Journal, reflection intensified Darwin’s perception of the singularity of the Galapagos fauna. “Considering the small size of these islands,” he says, “we feel the more astonished at the number of their aboriginal beings, and at their confined range. Seeing every height crowned with its crater, and the boundaries of most of the lava streams still distinct, we are led to believe that within a period geologically recent the unbroken sea was here spread out. Hence, both in space and time, we seem to be brought somewhat nearer to that great fact – that mystery of mysteries – the first appearance of new beings on this earth.” And he afterwards says, “One is astonished at the amount of creative force, if such an expression may be used, displayed on these small, barren, and rocky islands; and still more so at its diverse yet analogous action in points so near each other.”
The long voyage to Tahiti, 3,200 miles, begun on October 20, 1835, ending on November 15th, was succeeded by a most enjoyable stay. Darwin was as delighted as any traveller with the charms of the island and the islanders. His testimony to the quality of English products is worth noticing, if only as a piece of natural patriotism. He acknowledges that Tahitian pineapples are of excellent flavour, perhaps better than those cultivated in England, and this he believes to be the highest compliment which can be paid to a fruit, or indeed to anything else. He found reason to speak well of the influence of the Christian missionaries on the natives, and of the conscientiousness of the latter, in opposition to Kotzebue’s narrative.
On December 19th New Zealand was sighted. Our traveller’s observations here are of much value, as relating to a late period before civilised government was effectively established. At Waimate he was delighted with the effects produced by the religious teacher. “The lesson of the missionary is the enchanter’s wand,” and he rejoiced as an Englishman at what his countrymen had effected. The remarkable absence of land mammals, the late enormous increase of the imported Norway rat, the dock spreading far and wide, its seeds having been sold as tobacco seeds by a rascally Englishman, the huge Kauri pines, were all full of import to the inquiring mind; but New Zealand proved on the whole less attractive, as seen by Darwin, than most other countries he had visited. December 30th saw the Beagle on the way to Sydney, and Port Jackson was reached on January 12, 1836. An interesting excursion to the Blue Mountains and to Bathurst showed many aspects of colonial life, as well as the strange duckbill or platypus in its native haunts. Tasmania, with which island Darwin was greatly pleased, was visited in February. In April the Keeling Islands furnished much of the material for the future book on coral reefs, the essence of which is, however, included in the Journal. Mauritius, Cape Town, St. Helena, Ascension, Bahia, Pernambuco, Cape Verde, and the Azores were the successive stages of the homeward journey, and on October 2, 1836, anchor was cast at Falmouth, where the naturalist, equipped for his life work, was landed.
The high opinion Captain Fitzroy formed of Darwin during this long voyage is shown by many passages in his own narrative, and by many other references. He paid him the marked compliment of naming no fewer than three important geographical localities after him, namely, Mount Darwin and Darwin Sound (Tierra del Fuego), and Port Darwin in North Australia, thus connecting his name for future generations with two lands whose inhabitants were subjects of Darwin’s unceasing interest and investigation throughout life, and served in no small degree to elucidate the history and rise of mankind in Darwin’s mind and for a world’s instruction. Fitzroy complimented his friend markedly when himself receiving the medal of the Royal Geographical Society; and in one of his papers, speaking of him as a zealous volunteer in the cause of science, observed that his perseverance might be estimated from the fact that he never ceased to be a martyr to sea-sickness; while his interest in science and his public spirit were evident from his having presented his valuable collections to the public.
The concluding pages of the Journal are both eloquent and instructive. Everywhere there had been fascinating visions, and attractive problems remained unsolved. Was it not significant of future studies that the contrast between barbarian and civilised man should have been so impressed upon the future author of “The Descent of Man”? He writes thus on this subject, “Of individual objects, perhaps no one is more certain to create astonishment than the first sight in his native haunt of a real barbarian, of man in his lowest and most savage state. One’s mind hurries back over past centuries, and then asks, could our progenitors have been such as these? Men, whose very signs and expressions are less intelligible to us than those of the domesticated animals; men, who do not possess the instinct of those animals, nor yet appear to boast of human reason, or at least of arts consequent on that reason. I do not believe it is possible to describe or paint the difference between savage and civilised man. It is the difference between a wild and tame animal: and part of the interest in beholding a savage, is the same which would lead every one to desire to see the lion in his desert, the tiger tearing his prey in the jungle, the rhinoceros on the wide plain, or the hippopotamus wallowing in the mud of some African river.”
We have dwelt thus at length upon the history of this eventful voyage, not only because it filled an important space in Darwin’s life, but also because it undoubtedly gave rise to the thoughts and speculations which impelled him to devote his life to the study of problems of evolution. It has been shown to some extent, how he saw, without pre-arrangement, just those phenomena which could stimulate his mind, already fit, to its highest flights. We have seen, too, how universal was Darwin’s interest in nature, and how sympathetic a heart went with his scientific insight. He had yet to show how masterly was his patience, to work for yet twenty years, in order that he might not by premature publication of a crude theory risk defeat and throw science backward rather than forward. This long patient work was to be the triumph of his genius.
CHAPTER III
ON his return home, Darwin speedily placed himself in communication with the leaders of scientific progress, and, in consequence of the valuable results of his voyage, he soon found himself in a most advantageous position. On November 20, 1836, he was elected a Fellow of the Geological Society, and before the end of the year he had sent the manuscript of one of his early papers to Lyell, who writes to him (December 26, 1836): “I have read your paper with the greatest pleasure… What a splendid field you have to write upon.” He strongly advised the young man not to accept any official scientific place, but to devote himself to his own line of work. But Darwin was overpersuaded, and became a member of the Council of the Geological Society in the following February, and secretary in February, 1838. This office he held with success for three years. Lyell referred in considerable detail to the young traveller’s views in his presidential address to the Society in 1837.
Darwin’s geological papers soon became numerous. In 1837 he discussed in succession the recent elevation of the coast of Chili, the deposits containing extinct mammalia in the neighbourhood of the Plata, the areas of elevation and subsidence in the Pacific and Indian Oceans, as deduced from the study of coral formations, and the formation of mould (the precursor of a work he issued more than forty years later). Papers on the connection of certain volcanic phenomena, and on the formation of mountain chains, and other geological notes on South America, were read in 1838; the interesting Parallel Roads of Glen Roy, in Scotland, which he believed to be of marine origin, were described in 1839; the erratic (glacial) boulders of South America, in 1841; and coral reefs in 1842: a full record, one would imagine, of busy years, occupied also with secretarial work. Lyell, writing to Sir John Herschel (May 24, 1837), says: “I am very full of Darwin’s new theory of coral islands, and have urged Whewell to make him read it at our next meeting. I must give up my volcanic crater theory for ever, though it costs me a pang at first.” In March, 1838, Lyell describes the reception of the paper on volcanic phenomena at the Geological Society. “He opened upon De la Beche, Phillips, and others, his whole battery of the earthquakes and volcanoes of the Andes; and argued that spaces of a thousand miles long were simultaneously subject to earthquakes and volcanic eruptions, and that the elevation of the Pampas, Patagonia, &c., all depended upon a common cause.” In fit acknowledgment of such services to science, he was elected a Fellow of the Royal Society on January 24, 1839.
Early in 1839 Darwin married his cousin, Emma Wedgwood, daughter of his uncle Josiah Wedgwood: a union which, though consanguineous, proved in the highest degree congenial and fortunate. In succeeding years a numerous family of sons and daughters surrounded the happy parents. After considerable delays by the Admiralty, though it had long been ready, the Journal appeared, in 1839, as the third volume of Fitzroy’s “Voyages of The Adventure and Beagle.” The Quarterly Review (lxv. 224) said that there could be no two opinions of its merits. “We find ample materials for deep thinking; we have the vivid description that fills the mind’s eye with brighter pictures than painter can present, and the charm arising from the freshness of heart which is thrown over these virgin pages of a strong intellectual man, and an acute and deep observer.” Its merits, however, were somewhat slow to become known to the general public, owing to the original expensive form of publication; and it was not till 1845, when the second and enlarged edition appeared as “The Journal of Researches,” that the popular ear was gained. Later, under the title, “A Naturalist’s Voyage Round the World,” the book has become very widely known and appreciated.
The publication of “The Zoology of the Voyage of The Beagle,” commenced in 1838, under Darwin’s superintendence, gave a fuller view of the acquisitions to natural history which had been made than had previously been possible. The Treasury, acting on the representations of the presidents of the Linnean, Zoological, and Geological Societies, as well as of the naturalist himself, in 1837 made a grant of £1000 towards the expenses of publication of these memoirs. Owen’s description of the fossil mammalia, completed in 1840; G. Waterhouse’s of the living mammalia, in 1839; Gould’s of the birds, in 1841; L. Jenyns’s of the fish, in 1842; and Thomas Bell’s of the reptiles, in 1843 – all in quarto, with beautiful plates, were a solid testimony to a splendid success. Darwin furnished an introduction to each part, and the portions of the text referring to the habits and ranges of the living animals. Three species of mastodon and the gigantic megatherium were the only extinct mammalia known from South America previous to Darwin’s voyage. To these were now added the Mylodon Darwinii, a giant sloth; the scelidotherium, a somewhat smaller form; the great camel-like, yet odd-toed, macrauchenia; and the toxodon, as large as a hippopotamus, yet having a strange resemblance to the little rodents. All these belonged to geological deposits not far anterior to the present age. The collections of living vertebrates were less profoundly interesting, but the number of new species was large; and the habits and localities being recorded by so good an observer, gave them additional value.
The fossil mammals were given by the generous traveller to the London College of Surgeons, the mammals and birds to the Zoological Society, the reptiles to the British Museum, and the fishes to the Cambridge Philosophical Society. Nor was this all. The collections of insects, shells, and crustacea were described by many able specialists in scientific publications. The flowering plants were described by Hooker, and the non-flowering by Berkeley; and, altogether, no expedition ever yielded a more solid result to the scientific naturalist, while furnishing a delightful narrative to the general reader, and laying the foundation for generalisations of surpassing importance to all thinking minds.
It was evident to many geologists that the greatest value would attach to the full record of the geological observations made by the gifted young secretary of the Geological Society. A year after the publication of the Journal the first portion of these observations, dealing with coral reefs, was almost ready, but the continued ill-health of the author delayed the publication till 1842. When it appeared, under the title of “The Structure and Distribution of Coral Reefs,” its success was immediate and complete.
Ever since their first description by voyagers, marvel had been expressed at the strange and beautiful phenomena presented by coral islands. Coral, as being built up by the tireless labours of innumerable so-called “insects,” or “worms,” had become associated with romantic ideas. It really consists of the internal skeletons of coral-polyps, allied to the sea anemone. Captain Basil Hall, in his “Voyage to Loo Choo,” looking with the eyes of one ignorant of zoology, had credited the building of coral reefs to all kinds of creatures which lived on and near the coral after it had been made; and his erroneous views had been amplified and developed by James Montgomery, in his “Pelican Island,” into the most fantastically incorrect description that ever versifier penned. Sad to relate, his lines were often quoted, as if correct, by scientific men in pre-Darwinian times.
Nothing gives clearer evidence of the power of mind which Darwin had already attained when voyaging round the world than the originality of his views on coral reefs. The lagoon islands, or atolls, he describes as “vast rings of coral rock, often many leagues in diameter, here and there surmounted by a low verdant island, with dazzling white shores, bathed on the outside by the foaming breakers of the ocean; and, on the inside, surrounding a calm expanse of water which, from reflection, is of a bright, but pale, green colour.” Keeling atoll, outside which, at less than a mile and a half distance, no bottom was found with a line 7,200 feet in length, having been fully described, and an account given of all other known atoll systems, the peculiarities of the great barrier reef of North-east Australia, and that of New Caledonia, were recounted. Off the latter, no bottom was found, at two ships’ length from the reef, with a line 900 feet long. With these were linked the smaller reefs of Tahiti and others, where considerable islands are more or less completely surrounded by them. Next, the fringing or shore reefs, at first sight only a variety of barrier reefs, were clearly distinguished from them by the absence of an interior deep-water channel, and their not growing up from an immense, but from a moderate depth of water.
The remarkable fact was pointed out by Darwin that all coral islands are within a little more than 30 degrees of the Equator, but that, at the same time, they are absent over certain larger areas within the tropical seas. There are none on the West Coast of South America, nor on the West Coast of Africa. In this portion of his work we have another significant sentence bearing on the struggle for existence. In discussing the apparently capricious distribution of coral reefs, he remarks that “the study of the terrestrial and better-known half of the world must convince every one that no station capable of supporting life is lost – nay more, that there is a struggle for each station between the different orders of nature.” He describes the large fishes and the trepangs (holothuriæ) preying upon the coral-polyps, and shows how complex are the conditions which determine the formation of reefs on any shore. Perhaps no part of his work is more important than that in which he collects the evidence proving how rapidly coral masses grow, and that they for the most part cannot flourish in a greater depth of water than fifteen fathoms.
Reasoning upon the facts observed by himself and others Darwin now proceeded to upset the received theory that atolls were based upon submarine volcanic craters, and to substitute for it the view that there has been a prolonged and gradual subsidence of the areas upon which the atolls are based, and a corresponding upward growth of the reef-building corals. Thus fringing-reefs in time become barrier-reefs; and barrier-reefs, when they encircle islands, are converted into atolls, or lagoon islands, as soon as the last pinnacle of land sinks beneath the surface of the ocean. The whole matter is summed up thus: “A magnificent and harmonious picture of the movements which the crust of the earth has within a late period undergone is presented to us. We see vast areas rising, with volcanic matter every now and then bursting forth through the vents or fissures with which they are traversed. We see other wide spaces slowly sinking without any volcanic outbursts; and we may feel sure that this sinking must have been immense in amount as well as in area, thus to have buried over the broad face of the ocean every one of these mountains above which atolls now stand like monuments, marking the place of their former existence.” “No more admirable example of scientific method was ever given to the world,” says Professor A. Geikie, “and even if he had written nothing else, this treatise alone would have placed Darwin in the very front of investigators of nature.”
After thirty-two years’ interval, a second edition of “Coral Reefs” appeared, in a cheaper form, in 1874. It is rare indeed for a scientific treatise to attain at once and maintain so long a position of such undisputed authority. The eminent German naturalist, Semper, in 1863, criticised the general theory in consequence of his own careful examination of the Pelew Islands; but Darwin easily answered him by pointing to the cumulative evidence in favour of his own views. The only really important work on the subject, after Darwin’s, was that of Professor J. D. Dana, the eminent American naturalist and geologist, on “Corals and Coral Islands,” published in 1872. Darwin, in the preface to his second edition, candidly acknowledged that he had not previously laid sufficient weight on the mean temperature of the sea in determining the distribution of coral reefs; but this did not touch his main conception. In fact, he maintained his ground undisturbed, and at the same time admired greatly Dana’s book, which was the result of personal examination of more coral formations than perhaps any one man had ever studied, and which accepted Darwin’s fundamental proposition, that lagoon islands or atolls and barrier-reefs have been formed during periods of subsidence.5
No such strikingly original theory is propounded in the second part of “The Geology of the Beagle” dealing chiefly with volcanic islands. St. Jago, in the Cape de Verde Islands; Fernando Noronha, Terceira, Tahiti, Mauritius, St. Paul’s, Ascension, St. Helena, and the Galapagos are in turn more or less fully described, according to the opportunities the explorer had possessed. To some extent, as in the succeeding part, Darwin adapts his views on mountain elevation too closely to those enunciated by Elie de Beaumont. The third part of the geology of the Beagle, entitled “Geological Observations on South America,” was not published till 1846. Even this did not exhaust the contributions to geology made from the Beagle voyage, for it did not include the papers on the “Connection of certain Volcanic Phenomena in South America” (1838); on the “Distribution of Erratic Boulders” (1841); on the “Fine Dust which falls on Vessels” (1845); and on the “Geology of the Falkland Islands” (1846). A second edition of the two latter parts of “The Geology of the Beagle” was published in one volume in 1876.