The Cambridge Manuals of Science and Literature
THE COMING OF EVOLUTION
Cambridge University Press London: Fetter Lane, E.C. C. F. Clay, Manager
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THE COMING OF EVOLUTION
The Story of a Great Revolution in Science
JOHN W. JUDD C.B., LL.D., F.R.S.
Formerly Professor of Geology and Dean of the Royal College of Science
Cambridge: at the University Press 1910
Cambridge: Printed by John Clay, M.A. At the University Press
With the exception of the coat of arms at the foot, the design on the title page is a reproduction of one used by the earliest known Cambridge printer, John Siberch, 1521
I. Introductory 1
II. Origin of the Idea of Evolution 5
III. The Development of the Idea of Evolution to the Inorganic World 14
IV. The Triumph of Catastrophism over Evolution 20
V. The Revolt of Scrope and Lyell against Catastrophism 33
VI. The Principles of Geology 55
VII. The Influence of Lyell's Works 68
VIII. Early Attempts to establish the Doctrine of Evolution for the Organic World 82
IX. Darwin and Wallace: The Theory of Natural Selection 95
X. The Origin of Species 115
XI. The Influence of Darwin's Works 136
XII. The Place of Lyell and Darwin in History 149
Charles Darwin Frontispiece
G. Poulett Scrope to face p. 35
Charles Lyell " " 41
Alfred R. Wallace " " 110
When the history of the Nineteenth Century—'the Wonderful Century,' as it has, not inaptly, been called—comes to be written, a foremost place must be assigned to that great movement by which evolution has become the dominant factor in scientific progress, while its influence has been felt in every sphere of human speculation and effort. At the beginning of the Century, the few who ventured to entertain evolutionary ideas were regarded by their scientific contemporaries, as wild visionaries or harmless 'cranks'—by the world at large, as ignorant 'quacks' or 'designing atheists.' At the end of the Century, evolution had not only become the guiding principle of naturalists, but had profoundly influenced every branch of physical science; at the same time, suggesting new trains of thought and permeating the language of philologists, historians, sociologists, politicians—and even of theologians.
How has this revolution in thought—the greatest which has occurred in modern times—been brought about? What manner of men were they who were the leaders in this great movement? What the influences that led them to discard the old views and adopt new ones? And, under what circumstances were they able to produce the works which so profoundly affected the opinions of the day? These are the questions with which I propose to deal in the following pages.
It has been my own rare good fortune to have enjoyed the friendship of all the great leaders in this important movement—of Huxley, Hooker, Scrope, Wallace, Lyell and Darwin—and, with some of them, I was long on terms of affectionate intimacy. From their own lips I have learned of incidents, and listened to anecdotes, bearing on the events of a memorable past. Would that I could hope to bring before my readers, in all their nobility, a vivid picture of the characteristics of the men to whom science and the world owe so much!
For it is not only by their intellectual greatness that we are impressed. Every man of science is proud, and justly proud, of the grandeur of character, the unexampled generosity, the modesty and simplicity which distinguished these pioneers in a great cause. It is unfortunately true, that the votaries of science—like the cultivators of art and literature—have sometimes so far forgotten their high vocation, as to have been more careful about the priority of their personal claims than of the purity of their own motives—they have sometimes, it must be sadly admitted, allowed self-interest to obscure the interests of science. But in the story we have to relate there are no 'regrettable incidents' to be deplored; never has there occurred any event that marred the harmony in this band of fellow-workers, striving towards a great ideal. So noble, indeed, was the great central figure—Charles Darwin—that his senior Lyell and all his juniors were bound to him by the strongest ties of admiration, respect and affection; while he, in his graceful modesty, thought more of them than of himself, of the results of their labours rather than of his own great achievement.
It is not, as sometimes suggested, the striking out of new ideas which is of the greatest importance in the history of science, but rather the accumulation of observations and experiments, the reasonings based upon these, and the writings in which facts and reasonings are presented to the world—by which a merely suggestive hypothesis becomes a vivifying theory—that really count in making history.
Talking with Matthew Arnold in 1871, he laughingly remarked to me 'I cannot understand why you scientific people make such a fuss about Darwin. Why it's all in Lucretius!' On my replying, 'Yes! Lucretius guessed what Darwin proved,' he mischievously rejoined 'Ah! that only shows how much greater Lucretius really was,—for he divined a truth, which Darwin spent a life of labour in groping for.'
Mr Alfred Russel Wallace has so well and clearly set forth the essential difference between the points of view of the cultivators of literature and science in this matter, that I cannot do better than to quote his words. They are as follows:—
'I have long since come to see that no one deserves either praise or blame for the ideas that come to him, but only for the actions resulting therefrom. Ideas and beliefs are certainly not voluntary acts. They come to us—we hardly know how or whence, and once they have got possession of us we cannot reject them or change them at will. It is for the common good that the promulgation of ideas should be free—uninfluenced by either praise or blame, reward or punishment.'
'But the actions which result from our ideas may properly be so treated, because it is only by patient thought and work that new ideas, if good and true, become adopted and utilized; while, if untrue or if not adequately presented to the world, they are rejected or forgotten.'[A]
Ideas of Evolution, both in the Organic and the Inorganic world, existed but remained barren for thousands of years. Yet by the labours of a band of workers in last century, these ideas, which were but the dreams of poets and the guesses of philosophers, came to be the accepted creed of working naturalists, while they have profoundly affected thought and language in every branch of human enterprise.
[A] For References see the end of the volume.
ORIGIN OF THE IDEA OF EVOLUTION
In all ages, and in all parts of the world, we find that primitive man has delighted in speculating on the birth of the world in which he lives, on the origin of the living things that surround him, and especially on the beginnings of the race of beings to which he himself belongs. In a recent very interesting essay, the author of The Golden Bough has collected, from the records of tradition, history and travel, a valuable mass of evidence concerning the legends which have grown out of these speculations. Myths of this kind would appear to fall into two categories, each of which may not improbably be associated with the different pursuits followed by the uncivilised races of mankind.
Tillers of the soil, impressed as they must have been by the great annual miracle of the outburst of vegetable life as spring returns, naturally adopted one of these lines of speculation. From the dead, bare ground they witnessed the upspringing of all the wondrous beauty of the plant-world, and, in their ignorance of the chemistry of vegetable life, they imagined that the herbs, shrubs and trees are all alike built up out of the materials contained in the soil from which they grow. The recognition of the fact that animals feed on plants, or on one another, led to the obvious conclusion that the ultimate materials of animal, as well as of vegetable, structures were to be sought for in the soil. And this view was confirmed by the fact that, when life ceases in plants or animals, all alike are reduced to 'dust' and again become a part of the soil—returning 'earth to earth.' In groping therefore for an explanation of the origin of living things, what could be more natural than the supposition that the first plants and animals—like those now surrounding us—were made and fashioned from the soil, dust or earth—all had been 'clay in the hands of a potter.' The widely diffused notion that man himself must have been moulded out of red clay is probably accounted for by the colour of our internal organs.
Thus originated a large class of legendary stories, many of them of a very grotesque character. Even in many mediaeval sculptures, in this country and on the continent, the Deity is represented as moulding with his hands the semblance of a human figure out of a shapeless lump of clay.
But among the primitive hunters and herdsmen a very different line of speculation appears to have originated, for by their occupations they were continually brought into contact with an entirely different class of phenomena. They could not but notice that the creatures which they hunted or tended, and slew, presented marked resemblances to themselves—in their structures, their functions, their diseases, their dispositions, and their habits. When dogs and horses became the servants and companions of men, and when various beasts and birds came to be kept as pets, the mental and even the moral processes characterising the intelligence of these animals must have been seen by their masters to be identical in kind with those of their own minds. Do we not even at the present day compare human characteristics with those of animals, the courage of the lion, the cunning of the fox, the fidelity of the dog, and the parental affection of the bird? And the men, who depended for their very existence on studying the ways of various animals, could not have been less impressed by these qualities than are we.
Mr Frazer has shown how, from such considerations, the legends concerning the relations of certain tribes of men with particular species of animals have arisen, and thus the cults of 'sacred animals' and of 'totemism' have been gradually developed. From comparisons of human courage, sagacity, swiftness, strength or perseverance, with similar qualities displayed by certain animals, it was an easy transition to the idea that such characteristics were derived by inheritance.
In the absence of any exact knowledge of anatomy and physiology, the resemblances of animals to themselves would quite outbulk the differences in the eyes of primitive men, and the idea of close relationship in blood does not appear to have been regarded with distaste. In their origin and in their destiny, no distinction was drawn between man and what we now designate as the 'lower' animals. Primitive man not only feels no repugnance to such kinship:—
'But thinks, admitted to that equal sky, His faithful dog shall hear him company.'
It should perhaps be remembered, too, that, in the breeding of domestic animals, the great facts of heredity and variation could not fail to have been noticed, and must have given rise to reflection and speculation. The selection of the best animals for breeding purposes, and the consequent improvement of their stock, may well have suggested the transmutation of one kind of animal into a different kind, just as the crossing of different kinds of animals seems to have suggested the possible existence of centaurs, griffins and other monstrous forms.
How early the principles of variation and heredity, and even the possibility of improving breeds by selection, must have been appreciated by early men is illustrated by the old story of the way in which the wily Jacob made an attempt—however futile were the means he adopted—to cheat his employer Laban.
Yet, in spite of observed tendencies to variation among animals and plants, early man must have been convinced of the existence of distinct kinds ('species') in both the vegetable and animal worlds; he recognised that plants of definite kinds yielded particular fruits, and that different kinds of animals did not breed promiscuously with one another, but that, pairing each with its own kind, all gave rise to like offspring, and thus arose the idea of distinct 'species' of plants and animals.
It must be remembered, however, that for a long time 'the world' was believed to be limited to a few districts surrounding the Eastern Mediterranean, and the kinds or 'species' of animals and plants were supposed to number a few scores or at most hundreds. This being the case, the sudden stocking of 'the world' with its complement of animals and plants would be thought a comparatively simple operation, and the violent destruction of the whole a scarcely serious result. Even the possibility of the preservation of pairs of all the different species, in a ship of moderate dimensions, was one that was easily entertained and was not calculated to awaken either surprise or incredulity.
But how different is the problem as it now presents itself to us! In the year 1900 Professor S. H. Vines of Oxford estimated that the number of 'species' of plants that have been described could be little short of 200,000, and that future studies, especially of the lower microscopic forms, would probably bring that number up to 300,000. Last year, Mr A. E. Shipley of Cambridge, basing his estimate on the earlier one of Dr Guenther, came to the conclusion that the number of described animals must also exceed 300,000. On the lowest estimate then we must place the number of known species of plants and animals, living on the globe, as 600,000! And if we consider the numbers of new forms of plants and animals that every year are being described by naturalists—about 1500 plants and 1200 animals—if we take into account the inaccessible or as yet unvisited portions of the earth's surface, the very imperfectly known depths of the sea, and, in addition to these, the almost infinite varieties of minute and microscopic forms, I think every competent judge would consider a million as being probably an estimate below, rather than above, the number of 'species' now existing on the earth!
While some of these species are very widely distributed over the earth's surface, or in the waters of the oceans, seas, lakes and rivers, there are others which are as strikingly limited in their range. Many of the myriad forms of insect-life pass their whole existence, and are dependent for food, on a particular species of plant. Not a few animals and plants are parasitical, and can only live in the interior or on the outside of other plants and animals.
It will be seen from these considerations that in attempting to decide between the two hypotheses of the origin of species—the only ones ever suggested—namely the fashioning of them out of dead matter, or their descent with modification from pre-existing forms, we are dealing with a problem of much greater complexity than could possibly have been imagined by the early speculators on the subject.
The two strongly contrasted hypotheses to which we have referred are often spoken of as 'creation' and 'evolution.' But this is an altogether illegitimate use of these terms. By whatever method species of plants or animals come into existence, they may be rightly said to be 'created.' We speak of the existing plants and animals as having been created, although we well know them to have been 'evolved' from seeds, eggs and other 'germs'—and indeed from those excessively minute and simple structures known as 'cells.' Lyell and Darwin, as we shall presently see, though they were firmly convinced that species of plants and animals were slowly developed and not suddenly manufactured, wrote constantly and correctly of the 'creation' of new forms of life.
The idea of 'descent with modification,' derived from the early speculations of hunters and herdsmen, is really a much nobler and more beautiful conception of 'creation' than that of the 'fashioning out of clay,' which commended itself to the primitive agriculturalists.
Lyell writing to his friend John Herschel, who like himself believed in the derivation of new species from pre-existing ones by the action of secondary causes, wrote in 1836:—
When I first came to the notion, ... of a succession of extinction of species, and creation of new ones, going on perpetually now, and through an indefinite period of the past, and to continue for ages to come, all in accommodation to the changes which must continue in the inanimate and habitable earth, the idea struck me as the grandest which I had ever conceived, so far as regards the attributes of the Presiding Mind.'
And Darwin concludes his presentment of the doctrine of evolution in the Origin of Species in 1859 with the following sentence:—
'There is a grandeur in this view of life, with its several powers, having been originally breathed by the Creator 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.'
Compare with these suggestions the ideas embodied in the following lines—ideas of which the crudeness cannot be concealed by all the witchery of Milton's immortal verse:—
'The Earth obey'd, and straight, Op'ning her fertile womb, teem'd at a birth Innumerous living creatures, perfect forms, Limb'd and full grown. Out of the ground up rose As from his lair, the wild beast, where he wons In forest wild, in thicket, brake, or den; Among the trees they rose, they walk'd; The cattle in the fields and meadows green: Those rare and solitary, these in flocks Pasturing at once, and in broad herds upsprung. The grassy clods now calv'd; now half appear'd The tawny lion, pawing to get free His hinder parts, then springs, as broke from bonds, And rampant shakes his brinded mane.'
Can anyone doubt for a moment which is the grander view of 'Creation'—that embodied in Darwin's prose, or the one so strikingly pictured in Milton's poetry?
We see then that the two ideas of the method of creation, dimly perceived by early man, have at last found clear and definite expression from these two authors—Milton and Darwin. It is a singular coincidence that these two great exponents of the rival hypotheses were both students in the same University of Cambridge and indeed resided in the same foundation—and that not one of the largest of that University—namely Christ's College.
THE DEVELOPMENT OF THE IDEA OF EVOLUTION TO THE INORGANIC WORLD
We have seen in the preceding chapter that, with respect to the origin of plants and animals—including man himself—two very distinct lines of speculation have arisen; these two lines of thought may be expressed by the terms 'manufacture'—literally making by hand, and 'development' or 'evolution,'—a gradual unfolding from simpler to more complex forms. Now with respect to the inorganic world two parallel hypotheses of 'creation' have arisen, like those relating to organic nature; but in the former case the determining factor in the choice of ideas has been, not the avocations of the primitive peoples, but the nature of their surroundings.
The dwellers in the valleys of the Euphrates and Tigris could not but be impressed by the great and destructive floods to which those regions were subject; and the inhabitants of the shores and islands of the Aegean Sea, and of the Italian peninsula, were equally conversant with the devastations wrought by volcanic outbursts and earthquake shocks. As great districts were seen to be depopulated by these catastrophies, might not some even more violent cataclysm of the same kind actually destroy all mankind, with the animals and plants, in the comparatively small area then known as 'the world'? The great flood, of which all these nations appear to have retained traditions, was regarded as only the last of such destructive cataclysms; and, in this way, there originated the myth of successive destructions of the face of the earth, each followed by the creation of new stocks of plants and animals. This is the doctrine now known as 'Catastrophism,' which we find prevalent in the earliest traditions and writings of India, Babylonia, Syria and Greece.
But in ancient Egypt quite another class of phenomena was conspicuously presented to the early philosophers of the country. Instead of sudden floods and terrible displays of volcanic and earthquake violence, they witnessed the annual gentle rise and overflowings of their grand river, with its beneficent heritage of new soil; and they soon learned to recognise that Egypt itself—so far as the delta was concerned—was 'the gift of the Nile.'
From the contemplation of these phenomena, the Egyptian sages were gradually led to entertain the idea that all the features of the earth—as they knew it—might have been similarly produced through the slow and constant action of the causes now seen in operation around them. This idea was incorporated in a myth, which was suggested by the slow and gradual transformation of an egg into a perfect, growing organism. The birth of the world was pictured as an act of incubation, and male and female deities were invented to play the part of parents to the infant world. By Pythagoras, who resided for more than twenty years in Egypt, these ideas were introduced to the Greek philosophers, and from that time 'Catastrophism' found a rival in the new doctrine which we shall see has been designated under the names of 'Continuity,' 'Uniformitarianism' or 'Evolution.' How, from the first crude notions of evolution, successive thinkers developed more just and noble conceptions on the subject, has been admirably shown by Professor Osborn in his From the Greeks to Darwin and by Mr Clodd in his Pioneers of Evolution.
Poets, from Empedocles and Lucretius to Goethe and Tennyson, have sought in their verses to illustrate the beauty of evolutionary ideas; and philosophers, from Aristotle and Strabo to Kant and Herbert Spencer, have recognised the principle of evolution as harmonising with, and growing out of, the highest conceptions of science. Yet it was not till the Nineteenth Century that any serious attempts were made to establish the hypothesis of evolution as a definite theory, based on sound reasoning from careful observation.
It is true that there were men, in advance of their age, who in some cases anticipated to a certain extent this work of establishing the doctrine of evolution on a firm foundation. Thus in Italy, the earliest home of so many sciences, a Carmelite friar, Generelli, reasoning on observations made by his compatriots Fracastoro and Leonardo da Vinci in the Sixteenth Century, Steno and Scilla in the Seventeenth, and Lazzaro Moro and Marsilli in the Eighteenth Century, laid the foundations of a rational system of geology in a work published in 1749 which was characterised alike by courage and eloquence. In France, the illustrious Nicolas Desmarest, from his study of the classical region of the Auvergne, was able to show, in 1777, how the river valleys of that district had been carved out by the rivers that flow in them. Nor were there wanting geologists with similar previsions in Germany and Switzerland.
But none of these early exponents of geological theory came so near to anticipating the work of the Nineteenth Century as did the illustrious James Hutton, whose 'Theory of the Earth,' a first sketch of which was published in 1785, was a splendid exposition of evolution as applied to the inorganic world. Unfortunately, Hutton's theory was linked to the extravagancies of what was known at that day as 'Vulcanism' or 'Plutonism,' in contradistinction to the 'Neptunism' of Werner. Hutton, while rejecting the Wernerian notion of "the aqueous precipitation of basalt," maintained the equally fanciful idea that the consolidation of all strata—clays, sandstones, conglomerates, limestones and even rock-salt—must be ascribed to the action of heat, and that even the formation of chalk-flints and the silicification of fossil wood were due to the injection of molten silica!
What was still more unfortunate in Hutton's case was that, in his enthusiasm, he used expressions which led to his being charged with heresy and even with being an enemy of religion. His writings were further so obscure in style as often to lead to misconception as to their true meaning, while his great work—so far as the fragment which was published goes—contained few records of original observations on which his theory was based.
Dr Fitton has pointed out very striking coincidences between the writings of Generelli and those of Hutton, and has suggested that the latter may have derived his views from the eloquent Italian friar. But for this suggestion, I think that there is no real foundation. Darwin and Wallace, as we shall see later, were quite unconscious of their having been forestalled in the theory of Natural Selection by Dr Wells and Patrick Matthew; and Hutton, like his successor Lyell, in all probability arrived, quite independently, and by different lines of reasoning, at conclusions identical with those of Generelli and Desmarest.
Although, as we shall see, Hutton failed to greatly influence the scientific thought of his day, yet all will now agree with Lyell that 'Hutton laboured to give fixed principles to geology, as Newton had succeeded in doing to astronomy'; and with Zittel that 'Hutton's Theory of the Earth is one of the masterpieces in the history of geology.'
THE TRIUMPH OF CATASTROPHISM OVER EVOLUTION
There is no fact in the history of science which is more certain than that those great pioneers of Evolution in the Inorganic world—Generelli, Desmarest and Hutton—utterly failed to recommend their doctrines to general acceptance; and that, at the beginning of last century, everything in the nature of evolutionary ideas was almost universally discredited—alike by men of science and the world at large.
The causes of the neglect and opprobrium which befel all evolutionary teachings are not difficult to discover. The old Greek philosophers saw no more reason to doubt the possibility of creation by evolution, than by direct mechanical means. But, on the revival of learning in Europe, evolution was at once confronted by the cosmogonies of Jewish and Arabian writers, which were incorporated in sacred books; and not only were the ideas of the sudden making and destruction of the world and all things in it regarded as revealed truth, but the periods of time necessary for evolution could not be admitted by those who believed the beginning of the world to have been recent, and its end to be imminent. Thus 'Catastrophic' ideas came to be regarded as orthodox, and evolutionary ones as utterly irreligious and damnable.
There are few more curious facts in the history of science than the contrast between the reception of the teaching of the Saxon professor Werner, and those of Hutton, the Scotch philosopher, his great rival. While the enthusiastic disciples of the former carried their master's ideas everywhere, acting with missionary zeal and fervour, and teaching his doctrines almost as though they were a divine revelation, the latter, surrounded by a few devoted friends, saw his teachings everywhere received with persistent misrepresentation, theological vituperation or contemptuous neglect. Even in Edinburgh itself, one of Werner's pupils dominated the teaching of the University for half a century, and established a society for the propagation of the views which Hutton so strongly opposed.
When it is remembered that Hutton wrote at a time when 'heresy-hunting' in this country had been excited to such a dangerous extent, through the excesses of the French Revolution, that his contemporary, Priestley, had been hounded from his home and country for proclaiming views which at that time were regarded as unscriptural, it becomes less difficult to understand the prejudice that was excited against the gentle and modest philosopher of Edinburgh.
We have employed the term 'Catastrophism' to indicate the views which were prevalent at the beginning of last century concerning the origin of the rock-masses of the globe and their fossil contents. These views were that at a number of successive epochs—of which the age of Noah was the latest—great revolutions had taken place on the earth's surface; that during each of these cataclysms all living things were destroyed; and that, after an interval, the world was restocked with fresh assemblages of plants and animals, to be destroyed in turn and entombed in the strata at the next revolution.
Whewell, in 1830, contrasted this teaching with that of Hutton and Lyell in the following passage:—'These two opinions will probably for some time divide the geological world into two sects, which may perhaps be designated the "Uniformitarians" and the "Catastrophists." The latter has undoubtedly been of late the prevalent doctrine.' It is interesting to note, as showing the confidence felt in their tenets by the 'Catastrophists' of that day, that Whewell adds 'We conceive that Mr Lyell will find it a harder task than he imagines to overturn the established belief!'
Some authors have suggested that the doctrine taught by Generelli, Desmarest and Hutton, and later by Scrope and Lyell, for which Whewell proposed the somewhat cumbrous term 'Uniformitarianism,' but which was perhaps better designated by Grove in 1866 as 'Continuity,' was distinct from, and subsidiary to, Evolution—and this view could claim for a time the support of a very great authority.
In 1869, Huxley delivered an address to the Geological Society, in which he postulated the existence of 'three more or less contradictory systems of geological thought,' under the names of 'Catastrophism,' 'Uniformitarianism' and 'Evolution.' In this essay, distinguished by all his wonderful lucidity and forceful logic, Huxley sought to establish the position that evolution is a doctrine, distinct from and in advance of that of uniformitarianism, and that Hutton and Playfair—'and to a less extent Lyell'—had acted unwisely in deprecating the extension of Geology into enquiries concerning 'the beginning of things.'
But there is no doubt that Huxley at a later period was led to qualify, and indeed to largely modify, the views maintained in that address. In a footnote to an essay written in April 1887, he asserts 'What I mean by "evolutionism" is consistent and thoroughgoing uniformitarianism'; and in the same year he wrote in his Reception of the Origin of Species: 'Consistent uniformitarianism postulates evolution, as much in the organic as in the inorganic world.'
It is not difficult to trace the causes of this change in the attitude of mind with which Huxley regarded the doctrine of 'uniformitarianism.' He assures us 'I owe more than I can tell to the careful study of the Principles of Geology,' and again 'Lyell was for others as for me the chief agent in smoothing the road for Darwin.' From the perusal of the letters of Lyell, published in 1881, Huxley learned that the author of the Principles of Geology had, at a very early date, been convinced that evolution was true of the organic as well as of the inorganic world—though he had been unable to accept Lamarckism, or any other hypothesis on the subject that had, up to that time, been suggested. There can be little doubt, however, that a chief influence in bringing about the change in Huxley's views was his intercourse with Darwin—who was, from first to last, an uncompromising 'uniformitarian.'
We are fully justified, then, in regarding the teaching of Hutton and Lyell (to which Whewell gave the name of 'uniformitarianism') as being identical with evolution. The cockpit in which the great battle between catastrophism and evolution was fought out, as we shall see in the sequel, was the Geological Society of London, where doughty champions of each of the rival doctrines met in frequent combat and long maintained the struggle for supremacy.
Fitton has very truly said that 'the views proposed by Hutton failed to produce general conviction at the time; and several years elapsed before any one showed himself publicly concerned about them, either as an enemy or a friend.' Sad is it to relate that, when notice was at last taken of the memoir on the 'Theory of the Earth,' it was by bitter opponents—such 'Philistines' (as Huxley calls them) as Kirwan, De Luc and Williams, who declared the author to be an enemy of religion. Not only did Hutton, unlike the writers of other theories of the earth, omit any statement that his views were based on the Scriptures, but, carried away by the beauty of the system of continuity which he advocated, he wrote enthusiastically 'the result of this physical enquiry is that we find no vestige of a beginning—no prospect of an end.' This was unjustly asserted to be equivalent to a declaration that the world had neither beginning nor end; and thus it came about that Wernerism, Neptunism and Catastrophism were long regarded as synonymous with Orthodoxy, while Plutonism and 'Uniformitarianism' were looked upon with aversion and horror as subversive of religion and morality.
Almost simultaneously with the foundation of the Wernerian Society of Edinburgh (in 1807) was the establishment in London of the Geological Society. Originating in a dining club of collectors of minerals, the society consisted at first almost exclusively of mineralogists and chemists, including Davy, Wollaston, Sir James Hall, and later, Faraday and Turner. The bitter but barren conflict between the Neptunists and the Plutonists was then at its height, and it was, from the first, agreed in the infant society to confine its work almost entirely to the collection of facts, eschewing theory. During the first decade of its existence, it is true, the chief papers published by the society were on mineralogical questions; but gradually geology began to assert itself. The actual founder and first president of the society, Greenough, had been a pupil of Werner, and used all his great influence to discourage the dissemination of any but Wernerian doctrines—foreign geologists, like Dr Berger, being subsidised to apply the Wernerian classification and principles to the study of British rocks. Thus, in early days, the Geological Society became almost as completely devoted to the teaching of Wernerian doctrines as was the contemporary society in Edinburgh.
Dr Buckland used to say that when he joined the Geological Society in 1813, 'it had a very landed manner, and only admitted the professors of geology in Oxford and Cambridge on sufferance.'
But, gradually, changes began to be felt in this aristocratic body of exclusive amateurs and wealthy collectors of minerals. William Smith, 'the Father of English Geology'—though he published little and never joined the society—exercised a most important influence on its work. By his maps, and museum of specimens, as well as by his communications, so freely made known, concerning his method of 'identifying strata by their organic remains,' many of the old geologists, who were not aware at the time of the source of their inspiration, were led to adopt entirely new methods of studying the rocks. In this way, the accurate mineralogical and geognostical methods of Werner came to be supplemented by the fruitful labours of the stratigraphical palaeontologist. The new school of geologists included men like William Phillips, Conybeare, Sedgwick, Buckland, De la Beche, Fitton, Mantell, Webster, Lonsdale, Murchison, John Phillips and others, who laid the foundations of British stratigraphical geology.
But these great geological pioneers, almost without exception, maintained the Wernerian doctrines and were firm adherents of Catastrophism. The three great leaders—the enthusiastic Buckland, the eloquent Sedgwick, and the indefatigable Conybeare—were clergymen, as were also Whewell and Henslow, and they were all honestly, if mistakenly, convinced that the Huttonian teaching was opposed to the Scriptures and inimical to religion and morality. Buckland at Oxford, and Sedgwick at Cambridge, made geology popular by combining it with equestrian exercise; and Whewell tells us how the eccentric Buckland used to ride forth from the University, with a long cavalcade of mounted students, holding forth with sarcasm and ridicule concerning 'the inadequacy of existing causes.'
And Sedgwick at Cambridge was no less firmly opposed to evolutionary doctrine, eloquently declaiming at all times against the unscriptural tenets of the Huttonians.
I cannot better illustrate the complete neglect at that time by leading geologists in this country of the Huttonian teaching than by pointing to the Report drawn up in 1833, by Conybeare, for the British Association, on 'The Progress, Actual State and Ulterior Prospects of Geological Science.' This valuable memoir of 47 pages opens with a sketch of the history of the science, in which the chief Italian, French and German investigators are referred to, but the name of Hutton is not even mentioned!
And if positive evidence is required of the contempt which the early geologists felt for Hutton and his teachings, it will be found in the same author's introduction to that classical work, the Outlines of Geology (1822), in which he says of Hutton, after praising his views on granite veins and "trap rocks":—
'The wildness of many of his theoretical views, however, went far to counterbalance the utility of the additional facts which he collected from observation. He who could perceive in geology nothing but the ordinary operation of actual causes, carried on in the same manner through infinite ages, without the trace of a beginning or the prospect of an end, must have surveyed them through the medium of a preconceived hypothesis alone.'
John Playfair, the brilliant author of the Illustrations of the Huttonian Theory, died in 1819; under happier conditions his able work might have done for Inorganic Evolution what his great master failed to accomplish; but the dead weight of prejudice and the dread of anything that seemed to savour of infidelity was, at the time of the great European struggle against revolutionary France, too great to be removed even by his lucid statements and eloquent advocacy. James Hall and Leonard Horner, two faithful disciples of Hutton, who had joined the infant Geological Society, forsook it early, the former leaving it on account of the quarrel with the Royal Society, the latter retaining his fellowship and interest, but going to live at Edinburgh. Greenough, 'The Objector General,' as he was called, was left, fanatically opposing any attempt to stem the current that had set so strongly in favour of Wernerism and Neptunism, and the Catastrophic doctrines which all thought to be necessary conclusions from them. The great heroic workers of that day—while they were laying well and truly the foundations of historical geology—were, one and all, indifferent to, or violently opposed to, the Huttonian teaching. Neither Fitton nor John Phillips, who at a later date showed sympathy with evolutionary doctrines, were the men to fight the battle of an unpopular cause.
Attempts have been made by both Playfair and Fitton to explain how it was that Hutton's teaching failed to arrest the attention it deserved. The former justly asserted that the world was tired of the performances issued under the title of 'theories of the earth'; and that the condensed nature of Hutton's writings, with their 'embarrassment of reasoning and obscurity of style' are largely responsible for the neglect into which they fell.
Fitton, in 1839, wrote in the Edinburgh Review, 'The original work of Hutton (in two volumes) is in fact so scarce that no very great number of our readers can have seen it. No copy exists at present in the libraries of the Royal Society, the Linnean, or even the Geological Society of London!' He also points out that Hutton's work, and even the more lucid Illustrations of the Huttonian Theory, were almost unknown on the continent, owing to the isolation of Great Britain during the war; and he even suggests that the popularity of Playfair in this country may have not improbably led to the neglect of the original work of Hutton.
On the continent, indeed, the authority of Cuvier was supreme, and in his Essay on the Theory of the Earth, prefixed to his Opus magnum—the Ossemens Fossiles—the great naturalist threw the whole weight of his influence into the scale of Catastrophism. He maintained that a series of tremendous cataclysms had affected the globe—the last being the Noachian deluge—and that the floods of water that overspread the earth, during each of these events, had buried the various groups of animals, now extinct, that had been successively created.
If anything had been wanted in England to support and confirm the views that were then supposed to be the only ones in harmony with the Scriptures, it was found in the great authority of Cuvier. As Zittel justly says, Cuvier's theory of 'World-Catastrophies'—'which afforded a certain scientific basis for the Mosaic account of the "Flood," was received with special cordiality in England, for there, more than in any other country, theological doctrines had always affected geological conceptions.' Britain, which had produced the great philosopher, Hutton, had now become the centre of the bitterest opposition to his teachings!
But 'the darkest hour of night is that which precedes the dawn,' and while the forces of reaction in this country appeared to be triumphant over Hutton's teaching, there was in preparation, to use the words of Darwin, a 'grand work' ... 'which the future historian will recognise as having produced a revolution in natural science.'
THE REVOLT OF SCROPE AND LYELL AGAINST CATASTROPHISM
The year 1797, in which the illustrious Hutton died, leaving behind him the noble fragments of a monumental work, was signalised by the birth of two men, who were destined to bring about the overthrow of Catastrophism, and to establish, upon the firm foundation of reasoned observation, the despised doctrine of Uniformitarianism or Evolution—as outlined by Generelli, Desmarest and Hutton. These two men were George Poulett Thomson (who afterwards took the name of Scrope) and Charles Lyell. Both of them were, from their youth upwards, brought under the strongest influences of the prevalent anti-evolutionary teachings; but both emancipated themselves from the effects of these teachings, being led gradually by their geological travels and observations, not only to reject their early faith, but to become the champions of Evolution.
There was a singular parallel between the early careers of these two men. Both were the sons of parents of ample means, and were thus freed from the distractions of a business or profession, while throughout life they alike remained exempt from family cares. Each of them received the ordinary education of the English upper classes—Scrope at Harrow, and Lyell at Salisbury, in a school conducted by a Winchester master on public-school lines. In due course, the two young men proceeded to the University—Scrope to Cambridge, to come under the influence of the sagacious and eloquent Sedgwick, and Lyell to Oxford, to catch inspiration from the enthusiastic but eccentric Buckland. On the opening up of the continent, by the termination of the French wars, each of the young men accompanied his family in a carriage-tour (as was the fashion of the time) through France, Switzerland and Italy; and both utilised the opportunities thus afforded them, to make long walking excursions for geological study. They both returned again and again to the continent for the purpose of geological research, and in the year 1825, at the age of 28, found themselves associated as joint-secretaries of the Geological Society. By this time they had arrived at similar convictions concerning the causes of geological phenomena—convictions which were in direct opposition to the views of their early teachers, and equally obnoxious to all the leaders of geological thought in the infant society which they had joined.
It is interesting to note that each of these two young geologists arrived independently, as the result of their own studies and observations, at their conclusions concerning the futility of the prevailing catastrophic doctrines. This I am able to affirm, not only from their published and unpublished letters, but from frequent conversations I had with them in their later years.
Scrope, who was slightly the elder of the two friends, spent a considerable time in that wonderful district of France—the Auvergne—in the year 1821, and though he had not seen the map and later memoirs of Desmarest, he pourtrayed the structure of the country in a series of very striking panoramic views, and was led, independently of the great French observer, to the same conclusions as his concerning the volcanic origin of the basalts and the formation of the valleys by river-action. Scrope was at that time equally ignorant of the views propounded both by Generelli and by Hutton.
By April 6th, 1822, Scrope had completed his masterly work The Geology and Extinct Volcanoes of Central France, and had despatched it to England. It would be idle to speculate now as to what might have been the effect of that work—so full of the results of accurate observation, and so suggestive in its reasoning—had it been published at that time. It is quite possible that much of the credit now justly assigned to Lyell, would have belonged to his friend. Unfortunately, however, Scrope, instead of seeing his work through the press, determined first to make another tour in Italy. He arrived at Naples just in time to witness and describe the grandest eruption of Vesuvius in modern times, that of October 1822. What he witnessed then—the blowing away of the whole upper part of the mountain and the formation of a vast crater 1000 feet deep—made a profound impression on Scrope's mind. His interest thus strongly aroused concerning igneous phenomena, Scrope continued his travels and observations on the volcanic rocks of the peninsula of Italy and its islands, and was thus led to a number of important conclusions in theoretical geology, which he embodied in a work, published in 1825, entitled Considerations on Volcanos: the probable causes of their phenomena, the laws which determine their march, the disposition of their products, and their connexion with the present state and past history of the globe; leading to the establishment of a New Theory of the Earth.
It is only right to point out that, in calling this book a new 'Theory of the Earth,' Scrope had no intention of comparing it with Hutton's great work, with which he was at that time altogether unacquainted. Nevertheless, his conclusions, though independently arrived at, were almost identical with those of the great Scotch philosopher. But Scrope made the same mistake as Hutton had done before him. He allowed his theoretical conclusions to precede, instead of following upon an account of the observations on which they were based. Scrope's book is certainly one of the most original and suggestive contributions ever made to geological science; but the very speculative character of a large portion of the work led to the neglect of the really valuable hypotheses and acute observations which it contained. In the preface, however, the author gives a most striking and complete summary of the doctrine of Evolution as opposed to Catastrophism, in the inorganic world, as will be shown by the following extracts:—
Geology has for its business a knowledge of the processes which are in continual or occasional operation within the limits of our planet, and the application of these laws to explain the appearances discovered by our Geognostical researches, so as from these materials to deduce conclusions as to the past history of the globe.
The surface of the globe exposes to the eye of the Geognost abundant evidence of a variety of changes which appear to have succeeded one another during an incalculable lapse of time.
These changes are chiefly,
I. Variations of level between different constituent parts of the solid surface of the globe.
II. The destruction of former rocks, and their reproduction under another form.
III. The production of rocks de novo upon the earth's surface.
Geologists have usually had recourse for the explanation of these changes to the supposition of sundry violent and extraordinary catastrophes, cataclysms, or general revolutions having occurred in the physical state of the earth's surface.
As the idea imparted by the term Cataclysm, Catastrophe, or Revolution, is extremely vague, and may comprehend any thing you choose to imagine, it answers for the time very well as an explanation; that is, it stops further inquiry. But it has also the disadvantage of effectually stopping the advance of science, by involving it in obscurity and confusion.
If, however, in lieu of forming guesses as to what may have been the possible causes and nature of these changes, we pursue that, which I conceive the only legitimate path of geological inquiry, and begin by examining the laws of nature which are actually in force, we cannot but perceive that numerous physical phenomena are going on at this moment on the surface of the globe, by which various changes are produced in its constitution and external characters; changes extremely analogous to those of earlier date, whose nature is the main object of geological inquiry.
These processes are principally,
I. The Atmospheric phenomena.
II. The laws of the circulation and residence of Water on the exterior of the globe.
III. The action of Volcanos and Earthquakes.
The changes effected before our eyes, by the operation of these causes, in the constitution of the crust of the earth are chiefly—
I. The Destruction of Rocks.
II. The Reproduction of others.
III. Changes of Level.
IV. The Production of New Rocks from the interior of the globe upon its surface.
Changes which in their general characters bear so strong an analogy to those which are suspected to have occurred in the earlier ages of the world's history, that, until the processes which give rise to them have been maturely studied under every shape, and then applied with strict impartiality to explain the appearances in question; and until, after a long investigation, and with the most liberal allowances for all possible variations, and an unlimited series of ages, they have been found wholly inadequate to the purpose, it would be the height of absurdity to have recourse to any gratuitous and unexampled hypothesis for the solution of these analogous facts.
It was not till 1826, four years after the completion of the work, that Scrope managed to publish his book on the Auvergne, and to tear himself away from the speculative questions by which he had become obsessed. No one could be more candid than he was in acknowledging the causes of his failure to impress his views upon his contemporaries. Writing in 1858, he said of his Considerations on Volcanos:—
'In that work unfortunately were included some speculations on theoretic cosmogony, which the public mind was not at that time prepared to entertain. Nor was this my first attempt at authorship, sufficiently well composed, arranged or even printed, to secure a fair appreciation for the really sound and, I believe, original views on many points of geological interest which it contained. I ought, no doubt, to have begun with a description of the striking facts which I was prepared to produce from the volcanic regions of Central France and Italy, in order to pave the way for a favourable reception, or even a fair hearing, of the theoretical views I had been led from these observations to form.'
He adds that 'this obvious error was pointed out in a very friendly manner' in a notice of the memoir on The Geology of Central France, which was contributed by Lyell to the Quarterly Review in 1827.
Scrope's geological career however—though one of so much promise—was brought to a somewhat abrupt termination. In 1821 he had married the last representative and heiress of the Scropes, the old Earls of Wiltshire, and soon afterwards he settled down at the family seat of Castle Combe, eventually devoting his attention almost exclusively to social and political questions. From 1833 to 1868, when he retired from Parliament, he was member for Stroud; and though he seldom took part in the debates, he became famous as a writer of political tracts, thus acquiring the sobriquet of 'Pamphlet Scrope.' He himself used to relate an amusing incident at his own expense. His great friend Lord Palmerston, on being greeted with the question, 'Have you read my last pamphlet?' replied mischievously, 'Well Scrope, I hope I have!'
It is sad to relate that, owing to a carriage accident, Scrope's wife became a confirmed invalid and he had no child to succeed to the estate. Though cut off by other duties from the geological world, Scrope maintained his correspondence with his old friend Lyell, and, as we shall see in the sequel, was able to render him splendid service by the luminous though discriminating reviews of the Principles of Geology in the Quarterly Review. Throughout his life, however, Scrope preserved a love of geology, and occasionally contributed to the literature of the science; and in his closing years, when unable to travel himself, he gave to others the means of carrying on the researches in which he had from the first been so deeply interested.
* * * * *
Fortunately for science, Lyell's devotion to geological study was not, like Scrope's, interrupted by the claims made upon him by social and political questions. Feeling though he did, with his friend, the deepest sympathy in all liberal movements, and being especially interested in the reform of educational methods, his geological work always had the first claim on his time and attention, and nothing was allowed to interfere with his scientific labours.
Charles Lyell was the eldest son of a Scottish laird, whose forbears, after making a fortune in India, had purchased the estate of Kinnordy in Strathmore, on the borders of the Highlands. Lyell's father was a man of culture, a good classical scholar, a translator and commentator on Dante, and a cryptogamic botanist of some reputation.
Lyell's mother, an Englishwoman from Yorkshire, was a person of great force of character; this she showed when, on coming to Kinnordy, she found drunkenness so prevalent among the lairds of this part of Scotland, as to cause a fear on her part, that her husband might be drawn into the dangerous society: she therefore induced him, when their son Charles was only three months old, to abandon their Scottish home, and settle in the New Forest of Hampshire. Thus it came about that the future geologist, though born in Scotland, became, by education, habits and association, English.
Charles Lyell's attention was first drawn to geology by seeing the quartz-crystals and chalcedony exposed in the broken chalk-flints, which he, as a boy of ten, used to roll down, in company with his school-fellows, from the walls of Old Sarum. Like Charles Darwin, too, he became an ardent and enthusiastic collector of insects, and grew to be a tall and active young fellow, a keen sportsman, with only one drawback—a weakness of the eyes which troubled him through all his after life.
It was when at the age of seventeen he went to Oxford and came under the influence of Dr Buckland that Lyell first became deeply engrossed in geology.
Lyell used to tell many amusing stories of the oddities of his old teacher and friend Buckland. In his lectures, both in the University and on public platforms, Buckland would keep his audience in roars of laughter, as he imitated what he thought to be the movements of the iguanodon or megatherium, or, seizing the ends of his long clerical coat-tails, would leap about to show how the pterodactyle flew. Lyell became greatly attached to Buckland, who used to take him privately on geological expeditions. On one of these occasions, they were dining at an inn, where a gentleman at another table became greatly scandalised by Buckland's conversation and manners. The professor, seeing this, became more outrageous than ever, and on parting with Lyell for the night took the candle and placed it between his teeth, so as to illuminate the mouth-cavity exclaiming, 'There Lyell, practise this long enough and you will be able to do it as well as I do.' When Buckland had retired, the stranger revealed himself to Lyell as an old friend of his father's, adding 'I hope you will never be seen in the company of that buffoon again.' 'Oh! Sir,' said the startled undergraduate, 'that is my professor at Oxford!' But Buckland did not always originate the fun, for Lyell told me that, when the professor visited Kinnordy in his company, he led him a long tramp under promise of showing him 'diluvium intersected by whin dykes,' and, in the end, pointed to fields in a boulder-clay country separated by gorse ('whin') hedges ('dykes').
Buckland, as shown by his Vindiciae Geologicae (1820) and his Bridgewater Treatise (1836), was the most uncompromising of the advocates for making all geological teaching subordinate to the literal interpretation of the early chapters of Genesis; and in his Reliquiae Diluvianae (1823) he stoutly maintained the view that all the superficial deposits of the globe were the result of the Noachian deluge! He was indeed the great leader of the Catastrophists, and it is not surprising to find Lyell, while still under his influence, scoffing at 'the Huttonians.'
That Buckland greatly influenced Lyell in his youth, especially by inoculating him with his splendid enthusiasm for geology, there can be no doubt; and Lyell, far as he departed in after life from the views of his teacher, never forgot his indebtedness to the Oxford professor. Even in 1832, in publishing the second edition of the first volume of his Principles, he dedicated it to Buckland, as one 'who first instructed me in the elements of geology, and by whose energy and talents the cultivation of science in the country has been so eminently promoted.'
On leaving Oxford in 1819, at the age of twenty-two, Lyell joined the Geological Society. What were the dominant opinions at that time on geological theory among the distinguished men, who were there laying the foundations of stratigraphical geology, we have already seen. Lyell, in his frequent visits to the continent, became a friend of the illustrious Cuvier, whose strong bias for Catastrophism was so forcibly shown in his writings and conversation.
What then, we may ask, were the causes which led Lyell to abandon the views in which he had been instructed, and to become the great champion of Evolutionism?
It has often been assumed that Lyell was led by the study of Hutton's works to adopt the Uniformitarian' doctrines. But there is ample evidence that such was not the case. As late as the year 1839, Lyell wrote of Hutton, 'Though I tried, I doubt whether I fairly read half his writings, and skimmed the rest'; and he emphatically assured Scrope 'Von Hoff has assisted me most.'
The fact is certain that Lyell, quite independently, arrived at the same conclusions as Hutton, but by totally different lines of reasoning.
As early as 1817, when Lyell was only twenty years of age, he visited the Norfolk coast and was greatly impressed by the evidence of the waste of the cliffs about Cromer, Aldborough, and Dunwich; and three years later we find him studying the opposite kind of action of the sea in the formation of new land at Dungeness and Romney Marsh. All through his life there may be seen the results of these early studies in a tendency which he showed to overrate marine action; the chief defect in his early views consisting in not fully realising the importance of that subaerial denudation—of which Hutton was so great an exponent. But it was in his native county of Forfarshire that Lyell found the most complete antidote to the Catastrophic teachings. Buckland had taught him that the 'till' of the country had been thrown down, just 4170 years before, by the Noachian deluge: while Cuvier had asserted that the study of freshwater limestones proved them to differ from any recent deposit by their crystalline character, the absence of shells and the presence of plant-remains, as well as by the occasional occurrence in them of bands of flint. As the result of this, Cuvier and Brongniart had declared that the freshwater of the ancient world possessed properties which are not observed in that of modern lakes. Lyell visited Kinnordy from time to time between 1817 and 1824, and found on his father's estate and other localities in Strathmore a number of small lakes, lying in hollows of the boulder clay. These were being drained and their deposits quarried for the purpose of 'marling' the land; the excavations thus made showed that, under peat containing a boat hollowed out of the trunk of a tree, there were calcareous deposits, sometimes 16 to 20 feet in thickness, which passed into a rock, solid and crystalline in character as the materials of the older geological formations and containing the stems and fruits of the freshwater plant Chara (Stone wort).
With the help of Robert Brown the botanist, and of analyses made by Daubeny, with the advice of his life-long friend, Faraday, Lyell was able to demonstrate that from the waters of the Forfarshire lakes, containing the most minute proportions of calcareous salts, a limestone, identical in all respects with those of the older rocks of the globe, had been deposited, with excessive slowness, by the action of plant-life. He was thus enabled to supply a complete refutation of the views put forward by Buckland and Cuvier.
Thus while Hutton had been led to his conclusion concerning evolution in the inorganic world, by studying the waste going on in the weathered crags and the flooded rivers of his native land, Lyell's conversion to the same views was mainly brought about by the study of changes due to the action of the sea along the English coasts, and by studying the evidence of constant, though slow, deposition of limestone-rocks, by the seemingly most insignificant of agencies.
Lyell however did not by any means neglect the study of the action of rain and rivers. During his visits to Forfarshire, he had his initials and the date cut by a mason on many portions of the rocky river-beds about his home. Fifty years afterwards (in 1874) I visited with him the several localities, to ascertain what amount of waste had resulted from the constant flow of water over these hard rocks. It was in most cases singularly small, the inscriptions being still visible, though deprived of their sharpness; even the sandy detritus carried along by the streams, being buoyed up by the water, had not been able in half a century to wear away a thickness of half-an-inch of the hard rock. The most singular result we noticed was, that the leaden small shot fired by sportsmen, in the Highland tracts, whence these streams flowed, had collected in great numbers in hollows formed by the young geologist's inscriptions.
By his father's request, Lyell after leaving Oxford studied for the bar, but there is no doubt that his main interest was in geological study. He had made the acquaintance of Dr Mantell, and carried on a number of researches in the south of England either alone or with that geologist. Four years after joining the Geological Society, in which he was a constant worker, he became one of the secretaries. This was in 1823 when he was only 26 years of age. His frequent visits to Paris and to various parts of the continent enabled him to exchange ideas with many foreign naturalists, and it is clear from his correspondence that at this early period he had abandoned the Catastrophic doctrines of his teachers and friends.
Let us now consider the outside influences which were at work on Lyell's mind in these early days. In the year 1818, the eminent palaeontologist Blumenbach induced the University of Gottingen to offer a prize for an essay on 'The investigation of the changes that have taken place in the earth's surface conformation since historic times, and the applications which can be made of such knowledge in investigating earth revolutions beyond the domain of history.' A young German, Von Hoff, won the prize by a most able book, displaying great erudition, entitled The History of those Natural Changes in the Earth's Surface, which are proved by Tradition. The first volume of this work appeared in 1822, and treated of the results produced on the land by the action of the sea; the second volume, published in 1824, dealt with the effects of volcanoes and earthquakes. Von Hoff's learned work was confined to the collection of data from classical and other early authors bearing on these subjects, and to reasonings based on these records; for, unfortunately, he did not possess the means necessary for travelling and making observations in the districts described by him. Lyell acknowledges the great assistance afforded to him by these two volumes of Von Hoff's work, but, unlike that author, he was able to visit the various localities referred to, and to draw his own conclusions as to the nature of the changes which must have taken place. It is pleasant to be able to relate that the debt which he owed to Von Hoff was fully repaid by Lyell; for the learned German's third volume appeared after the issue of the Principles of Geology, and as Zittel assures us 'its influence on Von Hoff is quite apparent in the third volume of his work.'
At this period, too, Lyell had the advantage of travelling both on the continent and in various parts of Great Britain with the eminent French geologist, Constant Prevost, who had shown his courage by opposing some of the catastrophic teachings of the illustrious Cuvier himself.
Still more important to Lyell were the opportunities he enjoyed for comparing his conclusions with those of Scrope, who had joined the Geological Society in 1824, and became a joint secretary with Lyell in the following year. From both of them, in their old age, I heard many statements concerning the closeness and warmth of their friendship, and the constant interchange of ideas which took place between them at this time.
From Scrope, Lyell heard of the occurrence of great beds of freshwater limestone in the Auvergne, on a far grander scale than in Strathmore, with many other facts concerning the geology of Central France, which so greatly excited him as in the end to alter all his plans concerning the publication of his own book. As soon as Scrope's great work on Auvergne was published, Lyell undertook the preparation of a review for the Quarterly—and this review was a very able and discriminating production.
Although Lyell did not derive his views concerning terrestrial evolution directly from Hutton, as is sometimes supposed, there were two respects in which he greatly profited when he came to read Hutton's work at a later date.
In the first place, he was very deeply impressed by the necessity of avoiding the odium theologicum, which had been so strongly, if unintentionally, aroused by Hutton, of whom he wrote, 'I think he ran unnecessarily counter to the feelings and prejudices of the age. This is not courage or manliness in the cause of Truth, nor does it promote progress. It is an unfeeling disregard for the weakness of human nature, for it is our nature (for what reason heaven knows), but as it is constitutional in our minds, to feel a morbid sensibility on matters of religious faith, I conceive that the same right feeling which guards us from outraging too violently the sentiments of our neighbours in the ordinary concerns of the world and its customs, should direct us still more so in this.'
In the second place, Lyell was warned by the fate of Hutton's writings that it was hopeless to look for success in combatting the prevailing geological theories, unless he cultivated a literary style very different from that of the Theory of the Earth. Lyell's father had to a great extent guided his son's classical studies, and at Oxford, where Lyell took a good degree in classics, he practised diligently both prose and poetic composition. Lyell once told me that his tutor Dalby (afterwards a Dean) had put Gibbon's Decline and Fall of the Roman Empire into his hand with certain passages marked as 'not to be read.' When he had studied the whole work (of course including the marked passages) he said he conceived a profound admiration for the author's literary skill—and this feeling he retained throughout his after life. It is not improbable, indeed, that Lyell learned from Gibbon that a 'frontal attack' on a fortress of error is much less likely to succeed than one of 'sap and mine.' Lyell was always most careful in the composition of his works, sparing no pains to make his meaning clear, while he aimed at elegance of expression and logical sequence in the presentation of his ideas. The weakness of his eyes was a great difficulty to him, throughout his life, and, when not employing an amanuensis, he generally wrote stretched out on the floor or on a sofa, with his eyes close to the paper.
The relation of Lyell's views to those of Hutton, may best be described in the words of his contemporary, Whewell, whose remarks written immediately after the publication of the first volume of the Principles, lose nothing in effectiveness from the evident, if gentle, note of sarcasm running through them:—
'Hutton for the purpose of getting his continents above water, or manufacturing a chain of Alps or Andes, did not disdain to call in something more than common volcanic eruptions which we read of in newspapers from time to time. He was content to have a period of paroxysmal action—an extraordinary convulsion in the bowels of the earth—an epoch of general destruction and violence, to usher in one of restoration and life. Mr Lyell throws away all such crutches, he walks alone in the path of his speculations; he requires no paroxysms, no extraordinary periods; he is content to take burning mountains as he finds them; and, with the assistance of the stock of volcanoes and earthquakes now on hand, he undertakes to transform the earth from any one of its geological conditions to any other. He requires time, no doubt; he must not be hurried in his proceedings. But, if we will allow him a free stage in the wide circuit of eternity, he will ask no other favour; he will fight his undaunted way through formations, transition and floetz—through oceanic and lacustrine deposits; and does not despair of carrying us triumphantly from the dark and venerable schist of Skiddaw, to the alternating tertiaries of the Isle of Wight, or even to the more recent shell-beds of the Sicilian coasts, whose antiquity is but, as it were, of yester-myriad of years.'
Never, surely, did words written in a tone of banter constitute such real and effective praise!
But though it is certain that Lyell did not derive his evolutionary views from Hutton, yet when he came to write his historical introduction to the Principles, he was greatly impressed by the proofs of genius shown by the great Scotch philosopher, and equally by the brilliant exposition of those views by Playfair in his Illustrations. To the former he gave unstinted praise for the breadth and originality of his views, and to the latter for the eloquence of his writings—adopting quotations chosen from these last, indeed, as mottoes for his own work.
It is only just to add that for the violent prejudices excited by some of his contemporaries against Hutton's writings—as being directed against the theological tenets of the day and therefore subversive of religion—there is really no foundation whatever; and every candid reader of the Theory of the Earth must acquit its author of any such design. The passage quoted on page 51 could only have been written by Lyell at a time when he was still unacquainted with Hutton's works, and was misled by common report concerning them. It is interesting to note, however, that the passage occurs in a letter written in December 1827, that is after the first draft of the Principles of Geology had been 'delivered to the publisher,' and before the preparation of the historical introduction, which would appear to have led to the first perusal of Hutton's great work, and that of his brilliant illustrator, Playfair.
'THE PRINCIPLES OF GEOLOGY'
We have seen that as early as the year 1817, when he visited East Anglia, Lyell began to experience vague doubts concerning the soundness of the 'Catastrophist' doctrines, which had been so strongly impressed upon him by Buckland. And these doubts in the mind of the undergraduate of twenty years of age gradually acquired strength and definiteness during his frequent geological excursions, at home and abroad, during the next ten years. At what particular date the design was formed of writing a book and attacking the predominant beliefs of his fellow-geologists, we have no means of ascertaining exactly; but from a letter written to his friend Dr Mantell, we find that at one time Lyell contemplated publishing a book in the form of 'Conversations in Geology,' without putting his name to it. This was probably suggested by the manner in which Copernicus and Galileo sought to circumvent theological opposition in the case of Astronomical Theory.
But this plan appears to have been soon abandoned; and by the end of the year 1827, when he had reached the age of thirty, Lyell had sent to the printer the first manuscript of the Principles of Geology, proposing that it should appear in the course of the following year in two octavo volumes.
A great and sudden interruption to this plan occurred however, for just at this time Lyell was engaged in writing his review for the Quarterly of Scrope's work on The Geology of Central France, and while doing this his interest was so strongly aroused by the accounts of the phenomena exhibited in the Auvergne, that he was led for a time to abandon the task of seeing his own book through the press; and, having induced Murchison and his wife to accompany him, set off on a visit to that wonderful district. He also felt that, before completing the second part of his book, he needed more information concerning the Tertiary formations, especially in Italy.
Lyell had been very early convinced of the supreme importance of travel to the geologist. In a letter to his friend Murchison he said:—'We must preach up travelling, as Demosthenes did "delivery" as the first, second and third requisites for a modern geologist, in the present adolescent state of the science.'
And Professor Bonney has estimated that so far did he himself practise what he preached, that no less than one fourth of the period of his active life was spent in travel.
The joint excursion of Lyell and Murchison to the Auvergne was destined to have great influence on the minds of these pioneers in geological research; both became satisfied from their studies that, with respect to the excavation of the valleys of the country, Scrope's conclusions were irresistible; and in a joint memoir this position was stoutly maintained by them.
It is interesting to notice the impression made by these two great geologists on one another during this joint expedition.
Murchison wrote that he had seen in Lyell 'the most scrupulous and minute fidelity of observation combined with close application in the closet and ceaseless exertion in the field.'
But I recollect that Lyell once told me how difficult Murchison found it to restrain himself from impatience, when his companion's attention was drawn aside by his entomological ardour. In an early letter, indeed, we find that Murchison often expressed a wish that Lyell's sisters had been with them to attend to the insect-collecting and thus leave Lyell free for geological work.
On the other hand, Lyell informed me that Murchison had rendered him a great service in showing how much a geologist could accomplish by taking advantage of riding on horseback, and he declared in his letters that he 'never had a better man to work with than Murchison'; nevertheless he ridiculed his 'keep-moving-go-it-if-it-kills-you' system as—quoting from the elder Matthews—he called it.
On parting from Murchison and his wife, after the Auvergne tour, Lyell proceeded to Italy and for more than a year he was busy studying the Tertiary deposits of Lombardy, the Roman states, Naples and Sicily, and conferring with the Italian geologists and conchologists. Thus it came about that he was not free to resume the task of seeing the Principles through the press till February 1829.
Immediately after his return to England Lyell was compelled, with the assistance of his companion Murchison, to defend their conclusions concerning the excavations of valleys by rivers from a determined attack of Conybeare, who was backed up by Buckland and Greenough; the old geologists endeavoured to prove that the river Thames had never had any part in the work of forming its valley. It is interesting to find that, on this occasion, Sedgwick, who was in the chair, was so far influenced by the arguments brought forward by the young men, as to lend some aid to those who had come to be called the 'Fluvialists,' in contradistinction to the 'Diluvialists'; he went so far as to suggest that, with regard to the floods which the Catastrophist invoked, it would be wiser at present to 'doubt and not dogmatise.'
To what extent the MS. of the Principles, sent to the publisher in 1827, was added to and altered two years later, we have no means of knowing; but that the work was to a great extent rewritten would appear from a letter sent to Murchison by Lyell, just before his return to England. In it, he says:—
'My work is in part written, and all planned. It will not pretend to give even an abstract of all that is known in geology, but it will endeavour to establish the principle of reasoning in the science; and all my geology will come in as illustration of my views of those principles, and as evidence strengthening the system necessarily arising out of the admission of such principles, which, as you know, are neither more nor less than that no causes whatever have from the earliest time to which we can look back to the present, ever acted, but those that are now acting, and that they never acted with different degrees of energy from that which they now exert'; but in 1833, in dedicating his third volume to Murchison, he refers to the MS., completed in 1827, as a 'first sketch only of my Principles of Geology.'
At one period, Lyell contemplated again delaying publication till he had visited Iceland. In the end, however, after declining to act as professor of geology in the new 'University of London' (University College), he set himself down steadily to the task of seeing the book through the press. It was at this time that Lyell experienced a singular piece of good fortune, comparable with that which befel Darwin thirty years afterwards, by his book falling into the hands of a very sympathetic reviewer. John Murray, who had undertaken the publication of the Principles, was also the publisher of the Quarterly Review, and Lockhart, the editor of that publication, undertook that an early notice of the book should appear, if the proof-sheets were sent to the reviewer. Buckland and Sedgwick were successively approached on the subject of reviewing Lyell's book, but both declined on the ground of 'want of time'; though I strongly suspect that their real motive in refusing the task was a disinclination to attack—as they would doubtless have felt themselves compelled to do—a valued personal friend. Conybeare was, fortunately, thought to be out of the question, as Lockhart said he 'promises and does not perform in the reviewing line.'
Very fortunately at this juncture, Lockhart, who was in the habit of attending the Geological Society and listening to the debates (for as he used to say to his friends whom he took with him from the Athenaeum, 'though I don't care for geology, yet I do like to see the fellows fight') thought of Scrope. Although he had practically retired from the active work of the Geological Society at this time, Scrope was known as an effective writer, and, happily for the progress of science, he undertook the review of Lyell's book.
Although, of course, Lyell had no voice in the choice of a reviewer for the Principles, yet he could not fail to rejoice in the fact that it had fallen to his friend, who so strongly sympathised with his views, to introduce it to the public. While the book was being printed and the review of it was in preparation, a number of letters passed between Lyell and Scrope, and the latter, before his death, gave me the carefully treasured epistles of his friend, with the drafts of some of his replies. These letters, some of which have been published, throw much light on the difficulties with which Lyell had to contend, and the manner in which he strove to meet them.
As we have already seen, many of the leaders in the Geological Society at that day besides being strongly inclined to Wernerian and Cataclysmal views, had an honest, however mistaken, dread lest geological research should lead to results, apparently not in harmony with the accounts given in Genesis of the Creation and the Flood. Lyell, as this correspondence shows, was most anxious to avoid exciting either scientific or theological prejudice. He wrote, 'I conceived the idea five or six years ago' (that is in 1824 or 5) that 'if ever the Mosaic geology could be set down without giving offence, it would be in an historical sketch,' and 'I was afraid to point the moral ... about Moses. Perhaps I should have been tenderer about the Koran.' He further says 'full half of my history and comments was cut out, and even many facts, because either I, or Stokes, or Broderip, felt that it was anticipating twenty or thirty years of the march of honest feeling to declare it undisguisedly.'
Under these circumstances the publication by Scrope of his two long notices of the Principles in the Review which was regarded as the champion of orthodoxy, was most opportune. A very clear sketch was given in these reviews of the leading facts and the general line of argument; and at the same time the allowing of prejudice or prepossession to influence the judgment on such questions was very gently deprecated.
But Scrope's reviews did not by any means consist of an indiscriminate advocacy of Lyell's views. In one respect—that of the great importance of subaerial action as contrasted with marine action—Scrope's views were at this time in advance of those of Lyell, and he called especial attention to the direct effects produced by rain in the earth-pillars of Botzen. These Lyell had not at the time seen, but took an early opportunity of visiting. Scrope, too, was naturally much more speculative in his modes of thought than Lyell, and argued for the probably greater intensity in past times of the agencies causing geological change, and for the legitimacy of discussing the mode of origin of the earth. Lyell, like Hutton, argued that he saw 'no signs of a beginning,' but his characteristic candour is shown when he wrote:—
'All I ask is, that at any given period of the past, don't stop enquiry, when puzzled, by a reference to a "beginning," which is all one with "another state of nature," as it appears to me. But there is no harm in your attacking me, provided you point out that it is the proof I deny, not the probability of a beginning.'
Lyell clearly foresaw the opposition with which his book would be met and wisely resolved not to be drawn into controversy. He wrote:—
'I daresay I shall not keep my resolution, but I will try to do it firmly, that when my book is attacked ... I will not go to the expense of time in pamphleteering. I shall work steadily on Vol. II, and afterwards, if the work succeeds, at edition 2, and I have sworn to myself that I will not go to the expense of giving time to combat in controversy. It is interminable work.'
In order to maintain this resolve, Lyell, the moment the last sheet of the volume was corrected, set off for a four months' tour in France and Spain. While absent from England, he heard little of what was going on in the scientific world; but, on his return, Lyell was told by Murray that in the three months before the Quarterly Review article appeared, 650 copies of the volume, out of the 1500 printed, had been sold, and he anticipated the disposal of many more, when the review came out. This expectation was realised and led to the issue of a second edition of the first volume, of larger size and in better type.
Lyell, from the first, had seen that it would be impossible to avoid the conclusion that the principles which he was advancing with respect to the inorganic world must be equally applicable to the organic world. At first he only designed to touch lightly on this subject, in the concluding chapters of his first volume, and to devote the second volume to the application of his principles to the interpretation of the geological record. He, however, found it impossible to include the chapters on changes in the organic world in the first volume and then decided to make them the opening portion of the second volume.
It is evident, however, that as the work progressed, the interest of the various questions bearing on the origin of species grew in his mind. While Lyell found it impossible to accept the explanation of origin suggested by Lamarck, he was greatly influenced by the arguments in favour of evolution advanced by that naturalist; and as he wrote chapter after chapter on the questions of the modification and variability of species, on hybridity, on the modes of distribution of plants and animals, and their consequent geographical relations, and discussed the struggle of existence going on everywhere in the organic world, in its bearings on the question of 'centres of creation,' he found the second volume growing altogether beyond reasonable limits. His intense interest in this part of his work is shown by his remark, 'If I have succeeded so well with inanimate matter, surely I shall make a lively thing when I have chiefly to talk of living beings?'