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DARWIN'S CENTURY -- EVOLUTION AND THE MEN WHO DISCOVERED IT |
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Chapter III: The Pirate Chart
I. Time and Organic Change From the viewpoint of the historian of evolution the early decades of the nineteenth century are difficult to organize. Seemingly unrelated events, diverse scientific discoveries, industrial trends, and religious outlook can all, in historical perspective, be observed to revolve in a moment of seeming heterogeneity before they crystallize into a new pattern with Darwinism at the center. It is like looking into a chemical retort which is about to produce. some rare and many-sided crystal. One moment everything is in solution; there is a potentiality, no more -- and yet in the next instant a shape has appeared out of nowhere. It is difficult, as we have seen, to assess how much the men of this period influenced each other, for they were active contemporaries and, in many instances, were putting forth their views, either verbally or in letters, long before these were formally published. There is inevitable, therefore, a certain arbitrary quality in the assignment of honors though the leading books and thinkers are well enough known. The thinkers of the eighteenth century were devoted to their correspondence. Much of what today goes quickly into scientific journals passed back and forth in letters and often did not formally emerge for decades. More than one original idea remained in manuscript until it was finally expressed by someone else. Since letters are less often preserved than published documents, a period such as we are discussing has more than its share of tantalizing minor mysteries even though, for the purposes of formal history, they are pretty generally ignored. Having taken note of our historic limitations I now intend in the pages that follow to examine the question of time in the pre-Darwinian era. No theory of evolution can exist without an allotment of time in generous quantities. Yet it is just this factor which was denied to the questing scientist by the then current Christian cosmology. A change as vast as that existing between the Ptolemaic and Copernican systems of the heavens had to be effected in Western thinking upon the subject of time before one could even contemplate the possibility of extensive organic change; the one idea is an absolute prerequisite to the other. Let us see, therefore, how it was that the change was brought about. We will observe in the process that it involved two demonstrations: first, a proof that the world is old and, second, but without reference as yet to evolution, a proof that there has been a succession of life forms throughout the past history of the planet. II. Pagan and Christian Time Ever since man ceased to run like an uncaring beast through the sunlight of his living hours, he has dreamed of eluding time's shadow. He has sought fountains of youth in far lands, believed in some lost golden age before death came among men, some time of the ancestors when things were otherwise. But always the leaf has fallen from the tree, and man has seen his mortal generations descend into the dark. Three views, three insights may be said, therefore, to have characterized the human conception of time until the rise of stratigraphical geology. The first of these we may call primitive. It is the frail knowledge of the wandering hunter who drifts with the seasons but who knows no calendar and who leaves no record but his arrows in the earth. Among these men gray-headed elders may speak of many grasses or, perchance, of innumerable leaf falls, and then, speechless, they can only make a gesture and refer to the "dream time" or the "old ones." It is obvious that on this level of society man feels the touch of time emotionally but he cannot implement his feelings nor grasp the full significance of that vast waste across which today the astronomer and the geologist peer. Primitive man is confined to his own generation and some verbal memories of his father's time. The earth and the stars may be older but no one knows what that means and perhaps the question does not arise. Whether or not it does may depend on the creation myths of a given society. In the area of the East, however, in the region of the first great cultures which rose and fell many times in the early millennia of civilized consciousness, a different conception arose: notions of vast cycles and undulations in a time stream where things became and passed, perhaps only to come again. In these philosophies one catches the weariness of old civilizations surrounded by the broken monuments of their predecessors and looking with cynical eyes upon the doings of the gods themselves. Marcus Aurelius, one of the last great voices out of the Greco-Roman past, discourses as follows: "The periodic movements of the universe are the same, up and down from age to age. And either the universal intelligence puts itself in motion for every separate effect, and if this is so, be thou content with that which is the result of its activity; or it puts itself in motion once, and "everything comes by way of sequence in a manner; or indivisible elements are the origin of all things. -- In a word, if there is a god, all is well; and if chance rules, do not thou also be governed by it. "Soon will the earth cover us all: then the earth, too, will change, and the things also which result from change will continue to change for ever, and these again for ever. For if a man reflects on the changes and transformations which follow one another like wave after wave and their rapidity, he will despise everything which is perishable." With the rise of Christianity a sense of time totally un. like that entertained by the historically shallow primitive or the endless cycles over which Greco-Roman thought had brooded in antiquity took possession of the European mind. The Christian saw time, worldly time, as essentially the divine medium in which a great play-the drama of the human Fall and Redemption-was being played out upon the stage of the world. This drama was unique and not repetitious. Older pagan notions of eternal recurrent cycles were blasphemous to the Christian mind. "God forbid," protested St. Augustine, "that we should believe this. For Christ died once for our sins, and, rising again dies no more." Thus in the words of Professor Lynn White "the axiom of the uniqueness of the Incarnation required a belief that history is a straight line sequence guided by God. ... No more radical revolution has ever taken place in the world outlook of a large area." [1] Since man's historical knowledge of himself was incomplete, this great drama was estimated as consuming but a few trifling millennia terminated by a day of judgment. Worldly time, in other words, was of short duration. After the last judgment worldly time, historical time, would vanish, leaving that eternity which is the true home of God and the righteous in spirit. This interpretation of time and human destiny has gripped the imagination of the Western World for close to two thousand years. It was a philosophy which could only be sustained in its original version within a Ptolemaic cosmogony and in total ignorance of the facts of geology. Christian scholars generally assumed for the age of the world a figure of around six thousand years. James Ussher, Archbishop of Armagh, placed the beginning at 4004 B.C., but, although his date attained particular acceptance after 1650, like figures had been current and had achieved widespread popularity long before Ussher's estimate. These dates were generally worked out on the basis of calculations involving the ages of the post-Adamite generations as recorded in the Bible. [2] The judgment day, ending earthly time, was assumed to be not far distant. Some, in fact, impelled by the symmetry of the "great play," contended that the advent of Christ occupied the precise center of earthly time and that the day of judgment would come as many years after the death of Christ as there had been years before His birth. Others calculated an even shorter duration, so that the more fanatical sects were constantly proclaiming that the hour was at hand and seeking portents and signs to prove their case. Occasionally, even today, such prophecies continue to be heard Perhaps no other people have ever lived in such a curiously disparate time scheme as the Christian, whose material world was ephemeral, yet whose spiritual world, by contrast, was compounded of a kind of timeless eternal, beyond blemish and change. The rise of the new science was beginning as early as the seventeenth century to erode the foundations of this Christian mythos and the several evolutionary debates of the nineteenth century represent only successive steps in its hastening decline. Although we may recognize the frailties of Christian dogma and deplore the unconscionable persecution of thought which is, one of the less appetizing aspects of medieval history, we must also observe that in one of those strange permutations of which history yields occasional rare examples, it is the Christian world which finally gave birth in a clear articulate fashion to the experimental method of science itself. Many things undoubtedly went into that amalgam: Greek logic and philosophy, the experimental methods of craftsmen in the arts as opposed to the aristocratic thinker -- all these things have been debated. But perhaps the most curious element of them all is the factor dwelt upon by Whitehead -- the sheer act of faith that the universe possessed order and should be interpreted by rational minds. [3] For, as Whitehead rightly observes, [4] the philosophy of experimental science was not impressive. It began its discoveries and made use of its method in the faith, not the knowledge, that it was dealing with a rational universe controlled by a Creator who did not act upon whim nor interfere with the forces He had set in operation. The experimental method succeeded beyond men's wildest dreams but the faith that brought it into being owes something to the Christian conception of the nature of God. [5] It is surely one of the curious paradoxes of history that science, which professionally has little to do with faith, owes its origins to an act of faith that the universe can be rationally interpreted, and that science today is sustained by that assumption. By the seventeenth century hints of geological antiquity no longer completely escaped the attention of devout but attentive thinkers. We can catch the glimmer of this dawning age of science in the remarks of Ray as he stood at Bruges in 1663 marveling over a buried forest which had lain on the sea bottom and then become exposed on dry land once more. He saw "that of old time the bottom of the sea lay deep and that hundred foot thickness of earth arose from the sediments of those great rivers which there emptied themselves into the sea." It is a strange thing, he marveled, "considering the novity of the world, the age whereof, according to the usual account, is not yet 5600 years." [6] If buried forests trouble him, so do mountains. They are figuratively duplicated in his mind with, as in the words of a Christian poet, all their
Since the world has changed but little in the time of recorded history and "if the mountains were not from the beginning, either the world is a great deal older than is imagined, there being an incredible space of time required to work such changes ... or, in the primitive times, the creation of the earth suffered far more concussions and mutations in its superficial part than afterwards." [7] A correspondent raises the same problem. In 1691 Mr. Edward Lhwyd wrote to him about the fall of a huge stone from a mountain in Wales: "I gather that all the other vast Stones that lie in our mountainous Valleys have by such accidents as this fallen down: Unless perhaps we may do better to refer the greatest Part of them to the universal Deluge. For considering there are some thousands of them in these two valleys ... whereof there are but two or three that have fallen in the Memory of any Man now living; in the ordinary Course of Nature we shall be compelled to allow the rest many thousands of years more than the Age of the World." [8] Timidly Ray speculated as to whether certain shells might be those of creatures totally extinct, "a supposition which philosophers hitherto have been unwilling to admit." [9] But the cliff of fall yawns there before him. He cannot resist peering over: "Yet on the other side there follows such a train of consequences as seem to shock the Scripture -- history of the novity of the world; at least, they overthrow the opinion generally received, and not without good reason, among Divines and Philosophers that since the first creation there have been no species of animals or vegetables lost, no new ones produced" (1695). [10] To what new world-vaster, more awe-inspiringly time-worn -- these speculations were to lead, we have already begun to perceive as, on the threshold of the nineteenth century, we leave Lamarck fumbling uncertainly with the question of time and fossils-two parts of an unsolved puzzle. III. The Chart We have seen that as early as the middle of the seventeenth century Ray had concluded that "either the world is a great deal older than is imagined" or that at the time of creation the earth "suffered far more concussions and mutations in its superficial part than afterwards." Ray's insight here was almost preternaturally acute. In one small sentence he had unknowingly forecast the two lines of thinking which the geologist was destined to pursue throughout the next century and a half. Three men it now appears -- and all alive and active in that memorable last decade of the Enlightenment -- possessed essential fragments of the secret of the earth's past, but each was handicapped. They were like treasure· hunters into whose separate hands had come pieces of a pirate's map. One, a great brooding mind that alone might have put the chart together, was old and died two years after his last volume was published; one wandered the roads of England for a lifetime showing his map generously in taverns and speaking of it so simply and practically that no one imagined he had part of the secret of time. The third, a high official and a darling of the greatest court in Europe, possessed the strangest part of the chart and published an eloquent description of it, but if he saw its purport and whither it led, he was bound by the ethics . of his world, and unknowingly or willfully read into it a false latitude and longitude on a coast that never was. James Hutton (1726-97), William Smith (1769-1839), and the Baron Cuvier (1769-1832 ) -- together they possessed the secret of the past but they never sat down in the same tavern to put the chart together. Only James Hutton brooding over a little Scottish brook that carried sediment down to the sea felt the weight of the solid continent slide uneasily beneath his feet and cities and empires flow away as insubstantially as a summer cloud. IV. The Rise of Catastrophism If there is one mind that deserves to rank between the great astronomical geniuses of the seventeenth century and Charles Darwin in the nineteenth, it is James Hutton. Though he is spoken of in histories of science as the founder of historical geology, the public has never known his name as it knows that of Newton and Darwin. He discovered an intangible thing against which the human mind had long armored itself. He discovered, in other words, time -- time boundless and without end, the time of the ancient Easterners -- but in this case demonstrated by the very stones of the world, by the dust and the clay over which the devout passed to their places of worship. And James Hutton reaped the rewards of that discovery -- animus and charges of heresy -- or, even more bitter, silence and disdain. If it had not been for his devoted friend and follower John Playfair, he might have suffered the fate of Mendel half a century later and been totally, if temporarily, forgotten. Even as it is, one cannot help feeling that this sad, long face which gazes remotely out of the single portrait that has come down to us already has weighed human fame against the forces that waste continents into oblivion and turned away from man to some nobler inner source of serenity. It is the face of one who has looked so far that man has ceased to interest him, save as one might turn to glance at a strange bird on a pleasant morning stroll. Up to this point we have been primarily occupied with those who had been investigating the living world and the possible signs of animal transformation and gradation which could be observed there. Before Hutton's contribution can be properly assayed, however, it will be necessary to grasp what geological theory of the earth was held in Hutton's time. As one might have been led to suspect, it represented a compromise between the Biblical account of creation and the slowly growing observations of science. By the end of the eighteenth century catastrophism, as it came to be called, was the orthodox and accepted view of geology upon the past history of the earth. This catastrophic or cataclysmic geology has two versions, one of which succeeded the other, but both, because of a slowly increasing public awareness of fossils, were forced to take some account of stratigraphy and thus of time. The name of Abraham Werner, a German geologist, is associated with the first version and that of Georges Cuvier, the French paleontologist, with the second. In Hutton's day it was the theories of Werner to which he found' himself opposed. This "Neptunist" hypothesis accounted for the stratification of the earth's crust by the assumption that all the layers of rock had been precipitated out of a turbid universal sea which had once covered the entire planet. The primitive azoic rocks had been the first to be laid down, but had been shortly followed by the deposition of other materials containing fossils indicating a successive creation of forms of life. As the waters receded (where, no one was able satisfactorily to explain), advanced forms of mammalian life appeared. Gillispie has pointed out [11] that the scheme had a certain theological appeal because, depending upon one's beliefs, one could either claim a rapid or a slow succession of the Biblical "days of creation." In any case the appearance of life seemed to follow the order given in Genesis and to end with man. The second catastrophic doctrine which gained public attention shortly after Hutton's death and for a time totally submerged his theories is associated primarily with the name of Cuvier -- although Cuvier never urged successive creations but only migrations of fauna into new regions laid waste by geological upheaval. Catastrophism, so far as its biological aspect is concerned, is essentially a device to preserve the leading tenets of Christian theology and at the same time to give these doctrines a scientific cast. It preserves the assumption of special creation by assuming, instead of the one Biblical event, a multiple series of creations taking place successively in distinct geological epochs. It also, by implication, accepts the Noachian Deluge as the last in a series of tremendous upheavals or catastrophes which have separated one world of prehistoric life from another. At the close of each such revolution life· was supposed to be created anew. As the progressive organic advancement in the rocks became better known and read, it was assumed that this stair of life, which was analogous with the Scale of Being in the living world, pointed on prophetically toward man who was assumed to be the goal of the process of creation. It will thus be seen that there was a powerful supernatural element in this conception which was actually enhanced in early nineteenth- century England. We must be careful to remember, however, that at the time Hutton wrote his Theory of the Earth in 1785 this "progressionist" aspect of catastrophism was by no means fully elaborated. It would reach its culmination only after the contents of the stratified earth became better known. Peculiarly enough, French catastrophism seems to have arisen out of one of the earliest attempts to avoid supernaturalism in accounting for the past history of the globe. As we have earlier remarked, ideas of cosmic evolution were current in the mid-eighteenth century, mostly having derived from Descartes, and they thus achieved great popularity in France. Buffon in his Theorie de la Terre (1749) attempted to trace the history of our planet from the time when its substance escaped from the sun, through the successive "epochs of nature." He recognized that parallel strata "were not formed in an instant, but were gradually produced by successive sediments," and in spite of a greatly underestimated time scale, he recognized that erosion in its many forms "produced continual changes, which, in a succession of ages, become considerable. "Insensible changes, he came to believe, may over long time periods "cause very great revolutions." The word "revolution," as Dr. Tomkeieff pointed out a few years ago, meant to Buffon largely great changes and not the world-wide catastrophic upheavals into which it was soon to be translated. [12] Allowing for the state of information at the time he wrote, there is actually a Huttonian cast to Buffon's writing. By contrast, in the days following the French Revolution, Buffon's successor Cuvier gave a genuinely dramatic interpretation to the "revolutions" of the globe. Yet if one studies Buffon's use of the term one can see that he uses it variously as a synonym for change. The work of rivers, for example, he speaks of as inducing very slow "revolutions," whereas a volcanic outburst may produce quick alterations of the landscape. Cuvier, however, because of his work with fossil vertebrates in the Paris Basin was becoming far more conscious of the problem of extinction than his predecessors. Also, working as he was with vertebrates in which it was not easy to trace continuous evolutionary change, he seems to have drawn from Buffon, whom he admired, a somewhat reinterpreted and elaborated series of epochs succeeded in each instance by world catastrophes. After each of these epochs a new fauna and flora were assumed to have appeared. Although Cuvier himself left open the question of the origin of the new fauna it was not long before pure catastrophism was the reigning geological view. The last cataclysm was assumed to be represented by the Biblical deluge. The earlier epochs of life were generally regarded as equating figuratively with the days of creation. An enormous literature arose upon the subject and some writers projected over a score of successive creations and extinctions all based upon local disconformities of strata which were erroneously assumed to be world wide. The religious appeal of this system, particularly in the' days of the conservative English reaction against the French Revolution, was bound to make it widely popular. It accounted for extinct animals and at the same time preserved the essential foundations of contemporary religious belief. V. James Hutton's World Machine and Uniformitarianism There is a curious lag between the astronomical discovery of infinite space in the seventeenth century and the discovery of time in the last decade of the eighteenth century. Superficially it might have been expected that the one conception would rapidly force a recognition of the other. Actually, however, it appears that the Christian world retained a conception of the timeless Empyrean Heaven, even after its modification at the hands of science. The timeless Eternal of God was still not quite equated with the events of the mundane earth. Thus the realization of the scope of earthly time was resisted almost in the same manner that the concept of organic evolution lagged in acceptance behind the growing realization of cosmic evolution. Astronomical observations were too remote from reality, too dependent upon the mathematical calculations of a few virtuosi to bring the reality of time home to the average individual whose whole religious training was opposed to the idea. The man in the street, as in the days of the voyagers, was waiting for something he could handle and see with his own eyes -- as he had seen talking parrots from the Indies come ashore on the shoulders of sailors whose caravels were moored at the London docks. With Cuvier he would be granted that final demonstration, but first a theory had to be prepared, a key, a part of the map of time had to he envisaged, else no voyage into that distant region would be possible. James Hutton's triumph was that he proved that vast invisible ocean to exist. He measured its dimensions. The way to its toothed birds and dragons would be provided by other hands. The eighteenth century had seen, with the rise of the Newtonian doctrines in physics, the accompanying development of a philosophy in which God, the personal Divinity of earlier centuries, was more and more being relegated to the role of a spectator in His own universe. The Newtonian laws were such that the cosmic engine, once set spinning, was very largely self-regulatory. Miracles, providential interferences with the machinery, were no longer particularly acceptable. The passion for mathematical order was intense at the height of the Age of Reason. James Hutton had absorbed this atmosphere and the tone and the evident purpose of his book was to introduce into the history of the earth and the life upon its surface the same order and eternal perfection which Newton had perceived in the heavens. James Hutton, in other words, was the creator of a self-renewing world. machine whose laws of operation were as unswerving as the cosmic engine of the astronomers. In this respect he was following the scientific bent of his time. His misfortune lay in the fact that what had become acceptable in the heavens was still a heresy upon earth. Before Hutton almost everyone who discoursed upon the configuration of the landscape had felt obligated to assume that its major features were the product of the Hood. The strewn boulders of the glacial advances, often lying hundreds of miles from their point of origin, were thought to have been rolled and tossed by the turbulence of a giant Sea. Since the earth was supposed to have lain almost, if not entirely, under water, it then became a point of ingenuity for these early students of geology to explain into what monstrous caverns beneath the surface the Hood waters had withdrawn. Hutton, by contrast, proposed a reasonable but unorthodox solution. He did not attempt to "drain the pond.- Instead he contended that dynamic forces in the crust of the earth created tensions and stresses which, in the course of time, elevated new lands from the ocean bed even as other exposed surfaces were in the process of erosion. There had never been a universal Hood. There was observable in the buried shell. beds of the continents, which had long been taken as evidences of the Deluge, only the signs of subsidence and renewed uplift which were part of the eternal youth of the world. "We may perceive; Hutton pondered, "the actual existence of those productive causes, which are now laying the foundation of land in the unfathomable regions of the sea, and which will, in time, give birth to future continents." [13] With a Newtonian joy in his discovery of the principles of a remarkable engine, he informs his audience that the destructive work of winds and frost and running waters would eventually engulf the continents were there not "a reproductive operation, by which a ruined constitution [might] be again repaired." [14] In these words, in his affectionate regard for his "beautiful machine," one can observe the full climate of the Age of Enlightenment, its distaste for "having recourse to any unnatural supposition of evil, to any destructive accident in nature, or to the agency of any preternatural cause, in explaining that which actually appears." [15] The world is made by nature to decay but it is also made to renew itself eternally. "This decaying nature' of the solid earth," Hutton wrote in his later volumes, "is the very perfection of its constitution as a living world." [16] The restorative force which Hutton visualized from his long examination of solidified strata, and the careful distinction between sedimentary and igneous rock which he drew, was the internal heat of the earth. He observed that tilted and distorted strata implied uplift and wrinklings of the earth's crust in a manner suggesting "a power which has for principle subterraneous heat." Active volcanoes confirmed his view that this force was not a thing of the past but continued as an active agent in the creation of new lands and mountain ranges. In the depths of the sea the materials brought down from the continents are solidified by the subterranean forces into stone only to be again upthrust and to endure once more the forces of erosion. The earth, "like the body of animal, is wasted at the same time that it is repaired." Hutton's perception of the minute processes of decay is as keen as his eye for the vast movements of continental upheaval. So preternaturally acute was his sense of time that he could foretell in a running stream the final doom of a continent. Yet he saw also that in the long view this wastage foretold new worlds of life. "Thus ... from the top of the mountain to the shore of the sea ... everything is in a state of change; the rock and solid strata slowly dissolving, breaking and decomposing, for the purpose of becoming soil; the soil traveling along the surface of the earth on its way to the shore; and the shore itself wearing and wasting by the agitation of the sea, an agitation which is essential to the purposes of a living world. Without those operations which wear and waste the coast, there would not be wind and rain; and without those operations which wear and waste the solid land, the surface of the earth would become sterile." The man by the trickling brook had heard a roar like Niagara and seen a world go down into the torrent. In this eternal hurrying of particles across the surface of the land, in the dissolution of previous continents with all their varied life, there emerges once more into Western thought the long shadow of illimitable time as it was known to the Roman thinkers. The result of our present inquiry, wrote Hutton, at the close of his book, "is that we find no vestige of a beginning, -- no prospect of an end." Over sixty years after those words were written Sir Charles Lyell, addressing the annual meeting of the Geological Society of London, confessed that though "we have greatly enlarged the sphere of our knowledge, the same conclusion seems to me to hold true." [17] The way had opened for Darwin. James Hutton read his Theory of the Earth before the Royal Society of Edinburgh in 1785. It was published in the Proceedings of that society three years later. In 1795 an amplified two-volume edition was issued. His theory had been at first well received in liberal quarters. As he wrote in the edition of 1795: "When I first conceived my theory few naturalists could write intelligibly upon the subject; but that is long ago, and things are much altered since; now there are most enlightened men making observations and communicating natural knowledge. I have the satisfaction, almost every day, to compare the theory, which I had formed from my proper observations, with the actual state of things in almost every quarter of the globe." [18] The fantastic catastrophism which was to be one of the first products of vertebrate paleontology was then about to obscure his work. Of what he thought of evolution there is no record save that he spoke with interest of De Maillet's "ingenious theory." Its lack of supernaturalism and appeal to natural forces intrigued his interest but he dismissed it as "only a physical romance" though "better founded than most." [19] Hutton's view of time, and this is the one crucial limitation in his work, is essentially cyclical. He recognized its illimitable extent, he knew that throughout the slow obliteration of continents other lands were rising to the surface so that there was no reason to assume complete extinctions and successive creations of life. In the end, however, he did not commit himself upon the nature of the past flora and fauna of the planet. He observed that it could "translate" itself from one locality to another as time and paleo- geography permitted, but like most of the writers of his period, he allowed the similarities existing in early marine shells to deceive him as to the stability of the forms of life from age to age. Hutton was thus a total uniformitarian. "There are," he admitted, "varieties in those [ocean] species compared with the present animals which we examine, but no greater varieties than may perhaps be found ... in the different quarters of the globe. Therefore the sys- tern of animal life which had been maintained in the ancient sea, had not been different from that which now subsists...." [2] In order to prepare the public for the acceptance of the evolutionary theory two more steps must be taken, two more fragments of the pirate chart must now be fitted to the piece supplied by Hutton. Animal remains must be observed to lie in stratigraphic sequences and to be different in kind for different ages. This in turn demands a kind of anatomical knowledge With which Hutton was unfamiliar. VI. William Smith The astronomical theories which had so profoundly influenced Hutton and which had affected his philosophy of the world machine held, essentially, that in the celestial realm all perturbations of orbit tended to oscillate around a mean position so that even in the face of minor variation the solar system remained stable. It was this type of thinking which probably contributed to Hutton's indifference to the possibility of organic mutability. Evidences of change in marine forms were slight enough to be similarly dismissed as the minor variations of life around a standard type, a kind of thinking which, as we have previously seen, was a commonplace in Hutton's time. William Smith was a man of totally different background and a set of practical engineering needs. We have had previous occasion to remark that several individuals in the eighteenth century, Buffon for one, had suspected that fossils might prove of some use in determining the age of deposits in which they were found. That there was a seeming difference to be observed in the fossils of distinct strata had been noticed by James Woodward as early as 1695, [21] but he had not correctly interpreted the phenomenon, ascribing it to gravitational effects at the time of the universal Flood. That strata themselves had been laid down successively had also been noted or implied by several. [22] There is no doubt that Abraham Werner's views on successive stratification, first promulgated in 1777, stimulated interest in the geological layers of the planet, but they contributed little to the rational solution of the problems thus raised, since Werner's explanations involved chemical deposition in a universal ocean. [23] Werner was instrumental, however, in promoting research to determine the similarity of strata over wide regions. Though his theories are long outmoded, they undoubtedly led to a more rapid recognition of the extent and relationships of certain formations. This earlier research had largely revolved around the nature of the rocks involved rather than about the organisms contained in them. Smith introduced a totally new approach. The strata, he contended, can be identified by the fossils within them, and of any superimposed strata the lowest levels are also the oldest. This principle, which is now everywhere used in archaeology as well as paleontology, seems, like most great generalizations, amazingly simple once it has been stated. The fact that just as in the case of evolution itself many great minds had toyed unsuccessfully about the edges of the problem suggests what we have intimated so frequently before: an essential ingredient had been missing. Paleontology had lain undeveloped and interest had been less in time than in the mineral composition of deposits presumably laid down with great rapidity in a primeval ocean. As we have seen, Hutton published his views on time and erosion in 1788. Three years later William Smith seems to have had the secret of stratigraphy worked out though he did not publish his discovery until much later. The origins of William Smith were quite different from those of the highly literate and philosophically minded Hutton. He was orphaned at an early age and cared for by an uncle who was a farmer. Always attracted to the open fields and to fossils, he became an apprentice surveyor in his youth. By the time canals were being projected for the widespread transport of coal and other. goods in England, Smith had entered upon his professional career as a surveyor and engineer. Before the turn of the century and later, he traveled enormous mileages for canal companies. He reported upon coal deposits, drained swamps, laid out canal routes. He became, in other words, a practical field geologist much in demand for his unparalleled personal knowledge of ground waters and the complete composition of the English terrain. His entire living depended upon the accurate determination of strata and in tracing them successfully over wide areas. In examining exposed strata in commercial and natural deposits, Smith, "Strata Smith," as he came to be called, made the supreme observation that each individual stratum appeared to contain distinct organic ingredients. Smith, though it is unlikely that he fully realized what he had done, had discovered the strange historicity of life. In attempting to arrange sedimentary rocks which he would have been unable to classify on the basis of physical properties, he had selected and brought to attention the one thing on the planet which had consistently and identifiably altered itself throughout the long eras of the past, namely, life itself. William Smith made no secret of his discovery. In fact it is remarkable, and only because of honest friends, that he received credit for his work at all. Always on the move and detesting, as he did, the process of formal writing, he talked with the freedom of a traveling salesman to any attentive listener about his fragment of the great secret. By 1799 he had circulated an unpublished manuscript on the order of the strata in the vicinity of Bath in which he made use of his new paleontological principle. By 1813 a friend, the Rev. Joseph Townsend, had written a book in which Smith's discoveries are lauded, [24] and by 1815 Smith's real life work, the first geological map of England. was published. There followed a few papers elaborating his views and setting forth the evidence upon which they are based. Probably the best known is entitled The Stratigraphical System of Organized Fossils which was published in London in 1817. Smith flourished in a time when there was an economic demand for his type of specialized knowledge. He himself spoke regretfully of the fact that "the theory of geology was in the possession of one class of men, the practice in another." [25] In the light of these remarks it is most interesting that smith speaks respectfully of Lamarck's work on invertebrates "as most applicable to the arrangement of organized fossils." He was apparently familiar also with the work of Gustavus Brander and Daniel Solander, Fossila Hantoniensia (1766), which Lamarck had used in his pioneer effort to correlate the Tertiary fossil beds of Hampshire with those of France around the beginning of the century. Smith disclaimed a concern with theory "for," he said, "I have none to support." [26] Yet in this he was not entirely consistent. With others I have the distinct feeling, without having been able to consult all of the original documents, that Smith carried on his early work under uniformitarian influences emanating from Hutton and Lamarck, but that in his later years he turned toward the catastrophism which had become so universally popular after Cuvier's rise to prominence. The stratigraphical essay of 1817, in spite of the disclaimer we have just quoted, assumes that "each layer of these fossil organized bodies must be considered as a separate creation, or is," he also speculates, "an undiscovered part of an older creation." Although at one time he had evinced distaste for those who invoked unexplained "convulsions" to explain geological events, the conservative bent of the times and all the subtle pressures exerted by friends, position, and his own temperamental leanings led him finally to accept an unseen aspect to the geological past of the planet. "By the use of fossils," he contended, "we are carried back into a region of supernatural events." [27] In those words there is actually epitomized the reigning scientific climate of the early nineteenth century. It is a climate interested in science, increasingly interested in fossils, but firmly intent upon the preservation of religious orthodoxy. When William Smith, characterized by a contemporary as "a plain and moderately lettered man," directed the attention of science to his law of the superimposition of strata and their contained relics of organic life, the world, for the first time, began to realize the nature of time. All about, in commercial excavations, on seacoasts, and among broken uplands with their exposed formations, had been lying, unknown and uninterpreted, the remnants of the past. [28] Now suddenly the pretty shells in curio cabinets began to take on a vast and mysterious significance. Smith may not have accepted evolution but he had accepted time -- the time, essentially, of Hutton and Lamarck. ]29] Nor was that time any longer abstract and without meaning to the layman. The curious thread of living matter ran through it, unique and always changing, forever unpredictable. Cuvier had found strange bones in the Paris Basin but even the less impressive marine shells were becoming a worthy object of attention for young ladies. [30] Some people complained that Smith, who had no particular gift for writing, did not fulfill his publishing engagements, and they chafed in an irritated fashion over the delays. Once and for all the study of extinct life had been indissolubly joined to the rocks of the planet. The ladder into the past had been created and no phylogeny of a living creature could be worked upon again without checking against the story in the earth. If, because of the nature of his profession and his times, Smith chose to emphasize the breaks rather than the connections in the fossil record, the mistake would be remedied. He had been generous with his part of the great secret -- generous in a hard, dogged life that might well have led him to behave otherwise. In the year 1831 he was presented with the first Wollaston Medal of the Geological Society of London. It was given in recognition of the man who had found the way backward into time, and who had achieved that triumph while trudging over hill and dale in what many would have regarded as a grubby and not very genteel profession. The cloistered Scotch physician and the man whose face had been beaten by all the winds of England had done their solitary work. Apart from Smith but contemporaneous with him had labored a grander and more aristocratic figure, the inheritor of Buffon's mantle, the Baron Georges Cuvier. Hutton and Smith had been primarily physical geologists. Cuvier, who held the third secret of our figurative pirate's chart, was a comparative anatomist. He' was the real founder of vertebrate paleontology. VII. Cuvier: the Magician of the Charnel House It is a casual piece of folklore among laymen today that a paleontologist can always reconstruct an entire animal from a single bone. Most students of the science, who know their limitations, would smile and say "it depends on the bone." The public, however, has, for over a century now, been vastly impressed by the huge articulated skeletons erected in museums, and by the restorations of vanished reptiles, winged or bipedal Here is a magic with whose details the common man is little acquainted. Moreover, like the citizen on the London docks in the days of the voyagers, he can gaze upon these great bones, these spoils from the lost coasts of time, and believe more readily by beholding what it was he rejected when he turned away from Hutton and Lamarck. They, it is true, possessed the secret of time but it was lost like the sound of the sea in little shells. Only the huge bones, the saber teeth of cats, the tusks of giant elephants impress us with the marvelous organic diversity which strews the shores of continents that have vanished from the light. Man, convinced at first, in his naive innocence, that the world was made for him, has now been told by the time voyagers that, at a period not very remote, geologically speaking, the human form is no longer to be found. The outlines of this story, even the rearticulation of those giant bodies, we owe to the anatomical diligence of Cuvier and his followers. It is from his exploits, which brought him the title "magician of the charnel house," that the story of the paleontologist and the single bone has descended to us. Before scholars could go beyond the marine fauna and ascertain what type of life had roamed upon Hutton's lost continents, a method had to be perfected which would permit the investigation of a whole animal from a fragment. Land vertebrates, unlike shells, are infrequently found in total articulation. They are apt to have been torn to pieces after death by roving scavengers and birds, or, even if engulfed in muds and quicksands, the long erosion of time may have destroyed the larger part of the carcass before man comes upon it. Nature has no interest in the preservation of the dead; her purpose is to start their elements upon the eternal road of life once more. Thus out of innumerable vertebrate skeletons, here and there one is preserved under satisfactory conditions, and of these man may discover a few. The ability, as a consequence of this situation, to recognize a given form from fragments is tremendously important. It was this art which Cuvier carried to a high degree of perfection so that his exploits have come down to us as folklore. The beginnings of comparative anatomy like a good many aspects of our subject can be traced all the way back to the Greeks. Aristotle, for example, knew that the large animal groups shared a unity of structure which, in different species, was modified for different ends. [31] The gradations of the Scale of Being itself contributed to the promotion and continuation of such ideas. This does not necessarily imply an understanding of actual physical descent with modification. Rather it had been comprehended that animals were formed on a "plan," or "plans," which extended across whole groups of differing organisms. The plan might thus be seen as immaterial, a kind of Platonic form, a divine order manifesting itself in nature. As the eighteenth century drew on, however, unity of plan began to be considered as possibly indicating some kind of common physical origin for quite divergent forms. We have seen it emerge hesitantly in Buffon, and various shades or intimations of the same idea are not unknown to other French and German writers of the mid-eighteenth century, [32] considerably prior to Cuvier. Just as in the case of the theory of evolution itself, we may observe that there was a preliminary groping for the precise way in which this information might be used, considerably before the appearance of the master artist, Cuvier. Without detracting from Cuvier's genius we may point out that by the time he was ready to turn the unity of plan which existed in the living world into a method for probing the past. several things had occurred: (1) Attention, particularly on the continent, was shifting from shells to bones. News of American remains of huge bones were beginning to sift back to the Old World and, in some in stances, the bones themselves had been exhibited in Europe. (2) Smith's discoveries of a stratigraphic sequence in fossils, along with the obviously growing age of the world, heightened public interest as to what forms of land life might have existed contemporaneously along with the rather monotonously uniform invertebrate marine fossils. (3) The continually expanding geographical information upon other world areas now made it extremely unlikely that any large vertebrates were still hidden in unknown portions of the globe. Extinction, at last, was a reality. The past life of the earth, therefore, might offer marvels no living eye had beheld. (4) The rock formations of the Paris Basin were being quarried extensively in the days of the First Empire. There were strata interspersed with others containing fresh water forms, as well as later deposits containing numerous land animals of great size. An anonymous contemporary writer spoke in an awed tone of perished species and the mystery of how new species originated. "The mind is lost," he philosophized mournfully, "amid uncertain lights and gigantic images that pass before it." [33] It is in the lights and shadows of this vast, unfolding landscape that we find Cuvier like a modern Faust poring over the heaped bones recovered from these excavations. "I found myself as if placed in a charnel house," he once said, "surrounded by mutilated fragments of many hundred skeletons of more than twenty kinds of animals, piled confusedly around me. The task assigned me was to restore them all to their original positions. At the voice of comparative anatomy every bone and fragment of a bone resumed its place." [34] It is particularly satisfying that this modem magician who resurrected the vanished dead to live once more in the mind of man should have named the Pterodactyls. Like imps the leather-winged flying reptiles would have been most appropriate circling the master magician's head. The scene would have made a suitable painting, for Cuvier had a deep sense of drama. He knew these creatures to be the most extraordinary and outre of any that the spade had then revealed; he knew that they belonged utterly to a long vanished world. Yet he makes no exception of them. They, too, bone by bone and tooth by tooth, are amenable to the discipline of science. Strange- bodied and strangely adapted though they were, they are allied to an ancient reptilian pattern, a plan, a unity, that has come down through the long cycles of change into the present. The biologist could therefore say "Pterodactyls are gone but the pattern remains. They were reptilian vertebrates highly specialized and adapted for flight. In structure, however, they show a clear relationship to modern reptiles." The man who perfected and popularized this mode of penetration into the past was the son of a Swiss army officer in moderate circumstances. His early education was obtained at Stuttgart where he came under the influence of Kielmeyer. one of the early German students of anatomy. From 1788 to 1794 he was employed as a tutor to the son of a French count in Normandy. He thus escaped the vicissitudes of the revolution but through a fortunate connection was able to go to Paris in 1795. Here he entered upon a brilliant career at the Jardin des Plantes. He came to occupy. in addition, important positions of state, and was a favorite of Napoleon. Beginning in 1800 he published his Lessons in Comparative Anatomy in which he set forth the views he was later to apply so brilliantly In the investigation of the Parisian bone beds which he carried out In association with Alexandre Brongniart. [35] He wrote extensively and such works as Recherches sur Les Ossemens Fossiles (1812), Le Regne Animal (1817), and his Theory of the Earth (1815), which received a wide circulation in English, had a leading role in diffusing knowledge of comparative anatomy. All of these volumes passed through many editions. We have already mentioned his role in the development of the second phase of catastrophic geology; we will here confine ourselves to his "principle of correlation." Cuvier carefully pointed out that although vertebrate remains offered the hope of extensive insights into the past, they had been neglected because of their fragmentary condition. Few men were sufficiently equipped to read the meaning in bits of bone and their study had been neglected. It was just here that Cuvier, after long effort, produced his part of the lost map of time that fitted so well with the portions that Smith and Hutton had possessed. He said. in effect, "We will take what we have learned of the comparative anatomy of the living and we will use it as a ladder to descend into the past. All our information, scanty though it may be, leads us to assume that the same unity of design of which we observe evidences in the modem world extends also across the enormous time gulfs of the past. My key, my principle, will enable us to restore the appearance of those long vanished beasts and relate them to the life of the present." In order to perform his feats of identification and restoration Cuvier proceeded upon a principle that today might be labeled organismic or holistic. He regarded organs, in fact all anatomical structures, as so intimately related to the life of the entire creature that no one part can be fitted to perform a certain function without the modification of other related parts. Thus even a footprint may tell us a good deal about the structure of an animal of which we possess no other trace at all, or by a feather we may go on to infer many things about a bird simply because of known correlations of structure in all birds. "Thus," said Cuvier, "we procure astonishing results. The smallest fragment of bone, even the most apparently insignificant apophysis, possesses a fixed and determinate character, relative to the class, order, genus and species of the animal to which it belonged; insomuch, that when we find merely the extremity of a well-preserved bone, we are able by careful examination, assisted by analogy and exact comparison, tp. determine the species to which it once belonged, as certainly as if we had the entire animal before us." [36] So assiduously did Cuvier pursue his studies of the bones of both living and extinct animals that he was able to incite great wonder at his feats of identification. To give but one example: A fossil-bearing slab which had been secured near Lake Constance had been described by Johann Scheuchzer in 1726 as containing the skeleton of a man who lived before the Flood. This specimen, exhibited at Haarlem, had attracted great interest because of its supposed religious background, but in 1811 Cuvier examined the bones and revealed the creature to be a gigantic extinct salamander. The day had clearly passed when any obscure bone could be ascribed to a human giant or set aside as a saintly relic. Two other achievements of the Baron deserve mention here as having contributed to clearing the way for Darwin. One of these was his clear break with the Scale of Being hypothesis. It will be remembered that the eighteenth century was, on the whole, addicted to an ascending series of living forms shading by insensible degrees into each other and leading on to man. There was no consideration of the fact that this might be reading into Nature a greater unity than she actually possessed. It led inevitably to some highly questionable taxonomy produced in the effort to compress all life into positions upon a single stairway. Cuvier broke with this conception by the simple expedient of demonstrating anatomically that certain broad groups represented such divergent anatomical organization that they could not be fitted into a single unilineal ascending system. Instead, he conceived of four great groups: the Vertebrates, the Mollusca, the Articulata, and the Radiata. The last has suffered the most alteration by later work but, in essentials, he greatly improved the, taxonomical classification of animals and showed, even though he did not realize its evolutionary implications, that there were many stairways of life rather than one. The molluscan plan of organs and of adaptations could never be fitted successfully into a vertebrate sequence. Perhaps it was this sharp realization of distinct worlds of organization that caused him to reject evolution as savoring of the old Scale of Being whose clumsy morphology he detested. At any rate, all unknowingly, Cuvier had opened the way to a conception of divergent evolution which, though glimpsed timidly by Lamarck, had not been logically pursued to its conclusion by the latter. Whatever might be learned later of the original source of all life, it was evident from Cuvier's time on that the Scale of Nature, useful though it may have been in stimulating interest in the natural world while theology still dominated science, was, to a degree, a myth. There were several plans of life on the planet and by no stretch of the imagination, within the world open to man's investigation, could they be placed in an ascending relation to each other. Instead, each was unique and ramifying along its own evolutionary corridor. Man was not the creature toward which the worm was striving. Life was a bush, not a ladder. Finally, although averse to evolutionary explanations, Cuvier was the first to note of his Parisian studies, "There is a determinate order observable in the disposition of these bones in regard to each other, which indicates a very remarkable succession in the appearance of the different species." [37]He recognized clearly that the younger alluvial deposits contained creatures more similar to those of the present than strata representing more remote ages. He felt that the rocks revealed a gradual advance in the complexity of life through the several "revolutions" of the planet. This Deperet regards as "a fundamental idea," the merit of which has been too often forgotten. [38] Certainly it was the first clear evidence from the rocks of the organic advances in land life, the first satisfactory mammalian sequence from any quarry in the world. It was Cuvier's discoveries that gave the impetus to biological progressionism which, as will be seen, was the clear prelude to nineteenth- entury evolution. Moreover, Cuvier -- and this is occasionally forgotten by twentieth-century critics -- recognized the empirical quality of his law of correlation. He knew that increasing knowledge of the anatomy of extinct life would enhance our ability to pierce farther into the past and avoid the occasional mistakes which can be made with animal remains most distant from our common knowledge. It is perfectly true that a few of his correlations would not hold in the case of transitional or peculiarly divergent specimens we possess today. This does not, however, justify the dismissal of a method that has opened the doorway of the past. A bird like Archaeopteryx with feathers and teeth he would not have anticipated, but his own philosophy would have quickly adjusted to such exceptions for, as he himself wrote in advance of his critics, "our theoretical knowledge of these relations of forms is not sufficient to guide us, unless assisted by observation and experience." [39] He himself identified most successfully creatures who had reasonably similar living relatives. Furthermore, the man who in youth had laboriously painted in color the animal pictures in a treasured set of Buffon may, like a quiet child, have retained some private thoughts. Once he wrote cryptically, "Observation alone, independent entirely of general principles of philosophy, is sufficient to show that there certainly are secret reasons for all these relations of which I have been speaking." [40] When he wrote those lines, "descent with modification" was still thirty-five years away. The Baron Georges Cuvier was a proud and sometimes arrogant man of state. He was discreet. He had come a long road since the quiet days on the Normandy shore while the heads were falling in Paris. Perhaps he had his moment of hesitation, perhaps not. In any case he was one of the first great time voyagers. _______________ Notes: 1. Lynn White, "Christian Myth and Christian History," Journal of the History of Ideas, 1942, Vol. 3. p. 147. 2. Paul Kocher in his Science and Religion in Elizabethan England, San Marino, California, 1953, p. 152, points out, however, that the orthodox were sometimes harried by atheistical or doubting mathematicians who, in the words of Thomas Nashe, "will proove men before Adam." 3. A. N. Whitehead, Science and the Modern World, Mentor Book ed.. 1948, pp. 4-15. 4. Ibid., p. 17. 5. Ibid., p. 14. 6. Charles E. Raven, John Ray, Naturalist, cited p. 421. 7. Ibid., p. 425. 8. W. Derham, Philosophical Letters Between the Late Learned Mr. Ray and Several of His Ingenius Correspondents, Natives and Foreigners, London, 1718, p. 256. 9. Charles E. Raven, John Ray, Naturalist, cited p. 425. 10. Ibid., p. 437. 11. Genesis and Geology, Harvard University Press, 1951, p. 46. 12. S. J. Tomkeieff, "Geology in Historical Perspective," The Advancement of Science, 1950, Vol. 7, p. 65. 13. Essay of 1788, p. 293. 14. Ibid., p. 216. 15. Ibid., p. 285. 16. Theory of the Earth, Edinburgh, 1795, Vol. 1, p. 208. 17. Anniversary Address of the President, Quarterly Journal of the Geological Society of London, 1851, Vol. 7, p. Ixxiv ff. 18. Theory of the Earth, 1795, Vol. 1, p. 306. 19. Ibid., Vol. 1, p. 271. 20. Theory of the Earth, 1795, Vol. 1, pp. 175-76. 21. Essay Toward a Natural History a the Earth. 22. For a recent account of some of Smith's more obscure fore runners see C. J. Stubblefield's "The Relation of Paleontology to Stratigraphy," The Advancement of Science, 1954, Vol. 11, pp. 149-59. 23. F. D. Adams, Birth and Development of the Geological Sciences, Baltimore, 1938, p. 221 ff. 24. The Character of Moses established for Veracity as an Historian. Recording Events from Creation to the Deluge, Bath, 1813. 25. H. B. Woodward, The History of the Geological Society of London, London, 1907, p. 53. 26. Paper of 1817, cited above. p. vi. 27. F. J. North, "Deductions from Established Facts In Geology, by William Smith: Notes on a Recently Discovered Broadsheet," Geological Magazine, 1927, Vol. 64, p. 534. 28. the English series of formations was, for so small an area, remarkably complete. 29. Lamarck thought readily In terms of millions of years. See A. S. Packard, Lamarck, the Founder of Evolution, London, 1901, pp. 132-33. 30. Anonymous, "An Earnest Recommendation to Curious Ladies and Gentlemen Residing or Visiting In the Country, to Examine the Quarries, Cliffs, Steep Banks, etc., and collect and Preserve fossil shells as highly curious objects in Conchology, and, as most Important Aids in Identifying Strata in Distant Places; on which Knowledge the Progress of Geology in a principle degree if not Entirely Depends," The Philosophical Magazine and Journal, 1815, Vol. 45, pp. 274-80. 31. E. S. Russell, Form and Function, New York, 1917, p. 3 ff. 32. For a more lengthy account of these writers than can be attempted here the reader may consult E. S. Russell, op. cit., A. S. Packard, op. cit., pp. 136-39, and A. O. Lovejoy, "Some Eighteenth Century Evolutionists," Popular Science Monthly, 1904, Vol. 65. 33. Edinburgh Review, 1812, Vol. 20, p. 382. 34. Edinburgh Review, 1837, Vol. 65, p. 23. 35. Essai sur la geographia minerologique des environs de Paris, 1811. 36. Essay on the Theory of the Earth, Edinburgh, 1815. p. 101. 37. Op. cit, 1815. p. 109. 38. C. Deperet, The Transformations of the Animal World, New York, 1909, pp. 9-10. 39. Op. cit., 1815. p. 95. 40. Ibid. (Italics mine. L.E.)
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