Several thousand years ago, ere the upheaval of the last of our raised beaches, there existed somewhere on the British coast a submarine bed, rich in sea-weed and the less destructible zoophytes, and inhabited by the commoner crustaceæ and molluscs. Shoals of herrings frequented it every autumn, haunted by their usual enemies the dog-fish, the cod, and the porpoise; and, during the other seasons of the year, it was swum over by the ling, the hake, and the turbot. A considerable stream, that traversed a wide extent of marshy country, waving with flags and reeds, and in which the frog and the newt bred by millions, entered the sea a few hundred yards away, and bore down, when in flood, its modicum of reptilian remains, some of which, sinking over the submarine bed, found a lodgment at the bottom. Portions of reeds and flags were also occasionally entombed, with now and then boughs of the pine and juniper, swept from the higher grounds. Through frequent depositions of earthy matter brought down by the streamlet, and of sand thrown up by the sea, a gradual elevation of the bottom went on, till at length the deep-sea bed came to exist as a shallow bank, over which birds of the wader family stalked mid-leg deep when plying for food; and on one occasion a small porpoise, losing his way, and getting entangled amid its shoals, perished on it, and left his carcass to be covered up by its mud and silt. That elevation of the land, or recession of the sea, to which the country owes its last acquired marginal strip of soil, took place, and the shallow bank became a flat meadow, raised some six or eight feet above the sea-level. Herbs, shrubs, and trees, in course of time covered it over; and then, as century succeeded century, it gathered atop a thick stratum of peaty mould, embedding portions of birch and hazel bushes, and a few doddered oaks. When in this state, at a comparatively recent period, an Italian boy, accompanied by his monkey, was passing over it, when the poor monkey, hard-wrought and ill-fed, and withal but indifferently suited originally for braving the rigors of a keen northern climate, lay down and died, and his sorrowing master covered up the remains. Not many years after, the mutilated corpse of a poor shipwrecked sailor was thrown up, during a night-storm, on the neighboring beach: it was a mere fragment of the human frame,—a mouldering unsightly mass, decomposing in the sun; and a humane herd-boy, scooping out a shallow grave for it, immediately over that of the monkey, buried it up. Last of all, a farmer, bent on agricultural improvement, furrowed the flat meadow to the depth of some six or eight feet, by a broad ditch, that laid open its organic contents from top to bottom. And then a philosopher of the school of Maillet and Lamarck, chancing to come that way, stepped aside to examine the phenomena, and square them with his theory.
First, along the bottom of the deep ditch he detects marine organisms of a low order, and generally of a small size There are dark indistinct markings traversing the gray silt which he correctly enough regards as the remains of fucoids and blent with these, he finds the stony cells of flustra, the calcareous spindles of the sea-pen, the spines of echinus, and the thin granular plates of the crustacea. Layers of mussel and pecten shells come next, mixed up with the shells of buccinum, natica, and trochus. Over the shells there occur defensive spines of the dog-fish, blent with the button-like, thornset boucles of the ray. And the minute skeletons of herrings, with the vertebral and cerebral bones of cod, rest over these in turn. He finds, also, well-preserved bits of reed, and a fragment of pine. Higher up, the well-marked bones of the frog occur, and the minute skeleton of a newt; higher still, the bones of birds of the diver family; higher still, the skeleton of a porpoise; and still higher, he discovers that of a monkey, resting amid the decayed boles and branches of dicotyledonous plants and trees. He pursues his search, vastly delighted to find his doctrine of progressive development so beautifully illustrated; and last of all he detects, only a few inches from the surface, the broken remains of the poor sailor. And having thus collected his facts, he sets himself to collate them with his hypothesis. To hold that the zoophytes had been created zoophytes, the molluscs molluscs, the fishes fishes, the reptiles reptiles, or the man a man, would be, according to our philosopher, alike derogatory to the Divine wisdom and to the acumen and vigor of the human intellect: it would be “distressing to him to be compelled to picture the power of God, as put forth in any other manner than in those slow, mysterious, universal laws, which have so plainly an eternity to work in;” nor, with so large an amount of evidence before him as that which the ditch furnishes,—evidence conclusive to the effect that creation is but development,—does he find it necessary either to cramp his faculties or outrage his taste, by a weak yielding to the requirements of any such belief.
Meanwhile the farmer,—a plain, observant, elderly man, comes up, and he and the philosopher enter into conversation. “I have been reading the history of creation in the side of your deep ditch,” says the philosopher, “and find the record really very complete. Look there,” he adds, pointing to the unfossiliferous strip that runs along the bottom of the bank; “there, life, both vegetable and animal, first began. It began, struck by electricity out of albumen, as a congeries of minute globe-shaped atoms,—each a hollow sphere within a sphere, as in the well-known Chinese puzzle; and from these living atoms were all the higher forms progressively developed. The ditch, of course, exhibits none of the atoms with which being first commenced; for the atoms don’t keep;—we merely see their place indicated by that unfossiliferous band at the bottom; but we may detect immediately over it almost the first organisms into which—parting thus early into the two great branches of organic being—they were developed. There are the fucoids, first-born among vegetables,—and there the zoophytes, well nigh the lowest of the animal forms. The fucoids are marine plants; for, according to Oken, ‘all life is from the sea,—none from the continent;’ but there, a few feet higher, we may see the remains of reeds and flags,—semi-aqueous, semi-aerial plants of the comparatively low monocotyledonous order into which the fucoids were developed; higher still we detect fragments of pines, and, I think, juniper,—trees and shrubs of the land of an intermediate order, into which the reeds and flags were developed in turn; and in that peaty layer immediately beneath the vegetable mould, there occur boughs and trunks of blackened oak,—a noble tree of the dicotyledonous division,—the highest to which vegetation in its upward course has yet attained. Nor is the progress of the other great branch of organized being—that of the animal kingdom—less distinctly traceable. The zoophytes became crustacea and molluscs,—the crustacea and molluscs, dog-fishes and herrings,—the dog-fish, a low placoid, shot up chiefly into turbot, cod, and ling; but the smaller osseous fish was gradually converted into a batrachian reptile; in short, the herring became a frog,—an animal that still testifies to its ichthyological origin, by commencing life as a fish. Gradually, in the course of years, the reptile, expanding in size and improving in faculty, passed into a warm-blooded porpoise; the porpoise at length, tiring of the water as he began to know better, quitted it altogether, and became a monkey, and the monkey by slow degrees improved into man,—yes, into man, my friend, who has still a tendency, especially when just shooting up to his full stature, and studying the ‘Vestiges,’ to resume the monkey. Such, Sir, is the true history of creation, as clearly recorded in the section of earth, moss, and silt, which you have so opportunely laid bare. Where that ditch now opens, the generations of the man atop lived, died, and were developed. There flourished and decayed his great-great-great-great-grandfather the sea-pen,—his great-great-great-grandfather the mussel,—his great-great-grandfather the herring,—his great-grandfather the frog,—his grandfather the porpoise,—and his father the monkey. And there also lived, died, and were developed, the generations of the oak, from the kelp-weed and tangle to the reed and the flag, and from the reed and the flag, to the pine, the juniper, the hazel, and the birch.”
“Master,” replies the farmer, “I see you are a scholar and, I suspect, a wag. It would take a great deal of believing to believe all that. In the days of my poor old neighbor the infidel weaver, who died of delirium tremens thirty years ago, I used to read Tom Paine; and, as I was a little wild at the time, I was, I am afraid, a bit of a sceptic. It wasn’t easy work always to be as unbelieving as Tom, especially when the conscience within got queasy; but it would be a vast deal easier, Master, to doubt with Tom than to believe with you. I am a plain man, but not quite a fool; and as I have now been looking about me in this neighborhood for the last forty years, I have come to know that it gives no assurance that any one thing grew out of any other thing because it chances to be found atop of it, Master. See, yonder is Dobbin lying lazily atop of his bundle of hay; and yonder little Jack, with bridle in hand, and he in a few minutes will be atop of Dobbin. And all I see in that ditch, Master, from top to bottom, is neither more nor less than a certain top-upon-bottom order of things. I see sets of bones and dead plants lying on the top of other sets of bones and dead plants,—things lying atop of things, as I say, like Dobbin on the hay and Jack upon Dobbin. I doubt not the sea was once here, Master, just as it was once where you see the low-lying field yonder, which I won from it ten years ago. I have carted tangle and kelp-weed where I now cut clover and rye-grass, and have gathered periwinkles where I now see snails. But it is clean against experience, as my poor old neighbor the weaver used to say,—against my experience, Master,—that it was the kelp-weed that became the rye-grass, or that the periwinkles freshened into snails. The kelp-weed and periwinkles belong to those plants and animals of the sea that we find growing in only the sea; the rye-grass and snails, to those plants and animals of the land that we find growing on only the land. It is contrary to all experience, and all testimony too, that the one passed into the other, and so I cannot believe it; but I do and must believe, instead,—for it is not contrary to experience, and much according to testimony,—that the Author of all created both land productions and sea productions at the ‘times before appointed,’ and ‘determined the bounds of their habitation.’ ‘By faith we understand that the worlds were framed by the word of God;’ and I find I can be a believer on God’s terms at a much less expense of credulity than an infidel on yours.”
But in this form at least it can be scarce necessary that the argument should be prolonged.
The geological phenomena, I repeat, even had the author of the “Vestiges” been consulted in their arrangement, and permitted to determine their sequence, would fail to furnish a single presumption in favor of the development hypothesis. Does the ditch-side of my illustration furnish it with a single favoring presumption? The arrangement and sequence of the various organisms are complete in both the zoological and phytological branch. The flag and reed succeed the fucoid; the fir and juniper succeed the flag and reed; and the hazel, birch, and oak succeed the fir and juniper. In like manner, and with equal regularity, zoophytes, the radiata, the articulata, mollusca, fishes, reptiles, birds, and mammals, are ranged, the superior in succession over the inferior classes, in the true ascending order; and yet we at once see that the evidence of the ditch-side, amounting in the aggregate to no more than this, that the remains of the higher lie over those of the lower organisms, gives not a shadow of support to the hypothesis that the lower produced the higher. For, according to the honest farmer, the fact that any one thing is found lying on the top of any other thing, furnishes no presumption whatever that the thing below stands in the relation of parent to the thing above. And the evidence which the well-ranged organisms of the ditch-side do not furnish, the organisms of the entire geologic scale, even were they equally well ranged, would fail to supply. The fossiliferous portion of the ditch-side of my illustration may be, let us suppose, some five or six feet in thickness; the fossiliferous portion of the earth’s crust must be some five or six miles in thickness. But the mere circumstance of space introduces no new element into the question. Equally in both cases the fact of superposition is not identical with the fact of parental relation, nor even in any degree an analogous fact.
As, however, the succession of remains in the fossiliferous series of rocks is infinitely less favorable to the development hypothesis than that of the organisms of the ditch-side, it is not very surprising that the disciples of the development school should be now evincing a disposition to escape from the ascertained facts of Geology, and the legitimate conclusions based upon these, unto unknown and unexplored provinces of the science; or that they should be found virtually urging, that though some of the ascertained facts may seem to bear against them, the facts not yet ascertained may be found telling in their favor. Such, in effect, is the course taken by the author of the “Vestiges,” in his “Explanations,” when, availing himself of a difference of opinion which exists among some of our most accomplished geologists regarding the first epochs of organized existence, he takes part with the section who hold that we have not yet penetrated to the deposits representative of the dawn of being, and that fossil-charged formations may yet be detected beneath the oldest rocks of what is now regarded as the lowest fossiliferous system. Sir Charles Lyell and Mr. Leonard Hornet represent the abler and better-known assertors of this last view; while Sir Roderick Murchison and Professor Sedgwick rank among the more distinguished assertors of the antagonist one. It would be of course utterly presumptuous in the writer of these pages to attempt deciding a question regarding which such men differ; but in forming a judgment for myself, various considerations incline me to hold, that the point is now very nearly determined at which, to employ the language of Sir Roderick, “life was first breathed into the waters.” The pyramid of organized existence, as it ascends in the by-past eternity, inclines sensibly towards its apex,—that apex of “beginning” in which, on far other than geological grounds, it is our privilege to believe. The broad base of the superstructure, planted on the existing now, stretches across the entire scale of life, animal and vegetable; but it contracts as it rises into the past;—man—the quadrumana—the quadrupedal mammal—the bird—and the reptile—are each in succession struck from off its breadth, till we at length see it with the vertebrata, represented by only the fish, narrowing, as it were, to a point; and though the clouds of the upper region may hide its extreme apex, we infer from the declination of its sides, that it cannot penetrate much farther into the profound. When Steele and Addison were engaged in breaking up, piecemeal, their Spectator Club,—killing off good Sir Roger de Coverly with a defluction, marrying Will Honeycomb to his tenant’s daughter, and sending away Captain Sentry and Sir Andrew Freeport to their estates to the country,—it was shrewdly inferred that the “Spectator” himself was very soon to quit the field; and the sudden discontinuance of his lucubrations justified the inference. And a corresponding style of reasoning, based on the corresponding fact of the breaking up and piecemeal disappearance of the group of organized being, seems equally admissible. It is somewhat difficult to conceive how at least many more volumes of the geologic record than the known ones could be got up without the club. Further,—so far as yet appears, the fish must have lived in advance of the reptile during the three protracted periods of the Old Red Sandstone, the two still more protracted periods of the Upper and Lower Silurians, and the perhaps more protracted period still of the Cambrian deposits;—in all, apparently, a greatly more extended space than that in which the reptile lived in advance of the quadrupedal mammal, or the quadrupedal mammal lived in advance of man. On principles somewhat similar to those on which, with reference to the average term of life, the genealogist fixes the probable period of some birth in his chain of succession of which he cannot determine the exact date, it seems natural to infer that the birth of the fish should have taken place at least not earlier than the times of the Cambrian system.
There is another consideration, of at least equal, if not greater weight. A general correspondence is found to obtain in widely-separated localities, in the organic contents of that lowest band of the Lower Silurian or Cambrian system in which fossils have been detected. In Russia, in Sweden, in Norway, in the Lake district of England, and in the United States, there are certain rocks which occupy relatively the same place, and enclose what may be described generally as the same remains. They occur in Scandinavia as that “fucoidal band” of Sir Roderick Murchison which forms the base of the vast Palæozoic basin of the Baltic; they exist in Cumberland and Westmoreland as the Skiddaw slates of Professor Sedgwick, and bear also their fucoidal impressions, blent with graptolites; they are present in North America as those Potsdam sandstones of the States’ geologists in which fucoids so abound, mixed with a minute lingula, that they impart to some portions of the strata a carboniferous character. But with these deep-lying beds in all the several localities, thousands of miles apart, in which their passage into the inferior deposits has been traced, fossils cease. And why cease with them? In one locality the ancient ocean may have been of such a depth in the period immediately previous, and represented, in consequence, by the strata immediately beneath, that no animal could have lived at its bottom,—though I do not well see why the remains of those animals who, like the shark and pilot-fish, are frequently seen swimming over the profoundest depths, might not, did such exist at the time, be notwithstanding found at its bottom; or in another locality every trace of organization in the nether rocks may have been obliterated, at some posterior period, by fire. But it is difficult to imagine that that uniform cessation of organized life at one point, which seems to have conducted Sir Roderick Murchison and Professor Sedgwick to their conclusion, should have been thus a mere effect of accident. Accident has its laws, but uniformity is not one of them; and should the experience be invariable, as it already seems extensive, that immediately beneath the fucoidal beds organic remains cease, I do not see how the conclusion is to be avoided, that they represent the period in which at least existences capable of preservation were first introduced. Every case of coincident cessation which has occurred since the determination of the second case, must be reckoned, not simply as an additional unit in evidence, but, on the principles which determine mathematical probability, as a unit multiplied first by the chances against its occurrence, regarded as a mere contingency in that exact formation, and second, by the sum of all the previous occurrences at the same point.
In this curious question, however, which it must be the part of future explorers in the geological field definitely to settle, the Lamarckian can have no legitimate stake. It is but natural that, in his anxiety to secure an ultimate retreat for his hypothesis, he should desire to see that darkness in which ghosts love to walk settling down on the extreme verge of the geological horizon, and enveloping in its folds the first beginnings of life. But even did the cloud exist, it is, if I may so express myself, on its nearer side, where there is light,—not within nor beyond it, where there is none,—that the battle must be fought. It is to Geology as it is known to be, that the Lamarckian has appealed,—not to Geology as it is not known to be. He has summoned into court existing witnesses; and, finding their testimony unfavorable, he seeks to neutralize their evidence by calling from the “vasty deep,” of the unexamined and the obscure, witnesses that “won’t come,”—that by the legitimate authorities are not known even to exist,—and with which he himself is, on his own confession, wholly unacquainted, save in the old scholastic character of mere possibilities. The possible fossil can have no more standing in this controversy than the “possible angel.” He tells us that we have not yet got down to that base-line of all the fossiliferous systems at which life first began; and very possibly we have not. But what of that? He has carried his appeal to Geology as it is;—he has referred his case to the testimony of the known witnesses, for in no case can the unknown ones be summoned or produced. It is on the evidence of the known, and the known only, that the exact value of his claims must be determined; and his appeal to the unknown serves but to show how thoroughly he himself feels that the actually ascertained evidence bears against him. The severe censure of Johnson on reasoners of this class is in no degree over-severe. “He who will determine,” said the moralist, “against that which he knows, because there may be something which he knows not,—he that can set hypothetical possibility against acknowledged certainty,—is not to be admitted among reasonable beings.”
But the honest farmer’s reminiscences of his deceased neighbor the weaver, and his use at second-hand of Hume’s experience-argument, naturally lead me to another branch of the subject.