9. Millions of forest-trees sprang up, towered to heaven, and fell, to be crushed into the coal strata which make our winter fires. Hundreds of feet measure the thickness of what were once succulent plants, but pressed together like paper-pulp, and consolidated under a weight absolutely immensurable. Yet there remain the scales of their stems, the elegant reticulated patterns of their bark, the delicate tracery of their leaf-nerves, indelibly depicted by an unpatented process of "nature-printing." And when we examine the record,--the forms of the leaves, the structure of the tissues, we get the same result as before, that the plants belonged to a flora which had no species in common with that which adorns the modern earth. Very gradually, and only after many successions, not of individual generations, but of the cycles of species, genera, and even families, did the vegetable creation conform itself to ours.[48]

10. At length the species both of plants and animals grew,--not by alteration of their specific characters, but by replacement of species by species--more and more like what we have now on the earth, and finally merged into our present flora and fauna, about the time when we find the first geological traces of MAN.

11. During the course of these successive cycles of organic life, the map of the world has changed many times. Up to a late period the ocean washed over Mont Blanc and Mount Ararat; the continent of Europe was a wide sea; then it was a Polynesia, then an Archipelago of great islands, then a Continent much larger than it is now, with England united to it, and the solid land stretching far away into the Atlantic;--then it sank again, and was again raised, not all at once, but by several stages, each of which has left its coast line, and its shingle beach. All these changes must have been the work of vast periods of time.

"Excepting possibly, but not certainly, the higher parts of some mountains, which at widely different epochs have been upheaved, and made to elevate and pierce the stratified ma.s.ses which once lay over them, there is scarcely a spot on the earth's surface which has not been many times in succession the bottom of the sea, and a portion of dry land.

In the majority of cases, it is shown, by physical evidences of the most decisive kind, that each of those successive conditions was of extremely long duration; a duration which it would be presumptuous to put into any estimate of years or centuries; for any alteration, of which vestiges occur in the zoological state and the mineral const.i.tution of the earth's present surface, furnishes no a.n.a.logy (with regard to the nature and continuance of causes), that approaches in greatness of character to those changes whose evidences are discernible in almost any two continuous strata. It is an inevitable inference, unless we are disposed to abandon the principles of fair reasoning, that each one of such changes in organic life did not take place till after the next preceding condition of the earth had continued through a duration, compared with which six thousand years appear an inconsiderable fraction of time."[49]

12. The climate of our atmosphere has undergone corresponding mutations.

At one time the Palms, the Treeferns, the Cycads of the tropical jungles found their congenial home here: the Elephant, the Rhinoceros, and the Tiger roamed over England; nay, dwelt in countless hosts on the northern sh.o.r.es of Siberia: then the climate gradually cooled to a temperate condition: then it became cold, and glaciers and icebergs were its characteristic features: finally it became temperate again.

13. The icebergs and the glaciers were the ships and railways of past epochs; they were freighted with their heavy but worthless cargoes of rock-boulders and gravel, and set out on their long voyages and travels, over sea and land, sometimes writing their log-books in ineffaceable scratches on the rocky tables over which they pa.s.sed, and at length discharging their freights in harbours and bays, on inland plains, on mountain sides and summits, where they remain unclaimed, free for any trader in such commodities, without the ceremony of producing the original bill of lading.

Let the remainder be told in the words of one of our most eloquent and able geologists, Professor Sedgwick.

"The fossils demonstrate the time to have been _long_, though we cannot say _how_ long. Thus we have generation after generation of sh.e.l.l-fish, that have lived and died on the spots where we find them; very often _demonstrating_ the lapse of _many years_ for a few perpendicular inches of deposit. In some beds we have large, cold-blooded reptiles, creatures of long life. In others, we have traces of ancient forests, and enormous fossil trees, with concentric rings of structure, marking the years of growth. Phenomena of this kind are repeated again and again; so that we have three or four distinct systems of deposit, each formed at a distinct period of time, and each, characterised by its peculiar fossils. Coeval with the Tertiary ma.s.ses, we have enormous lacustrine deposits; sometimes made up of very fine thin laminae, marking slow tranquil deposits. Among these laminae, we can find sometimes the leaf-sheddings and the insects of successive seasons. Among them also we find almost mountain-ma.s.ses of the _Indusioe tubulatoe_ [the cases of _Phryganeoe_], and other sheddings of insects, year after year.

Again, streams of ancient lava alternate with some of these lacustrine tertiary deposits.

"In central France, a great stream of lava caps the lacustrine limestone. At a _subsequent period_ the waters have excavated deep valleys, cutting down into the lacustrine rock-marble many hundred feet; and, at a newer epoch, anterior to the authentic history of Europe, new craters have opened, and fresh streams of lava have run down the existing valleys. Even in the Tertiary period we have thus a series of demonstrative proofs of a long succession of physical events, each of which required a long lapse of ages for its elaboration.

"Again, as we pa.s.s downwards from the bottom Tertiary beds to the Chalk, we instantly find new types of organic life. The old species, which exist in millions of individuals in the upper beds, disappear, and new species are found in the chalk immediately below. This fact indicates a long lapse of time. Had the chalk and upper beds been formed simultaneously at the same period [as the supporters of the diluvial theory represent], their organic remains must have been more or less mixed; but _they are not_. Again, at the base of the Tertiary deposits resting on the Chalk, we often find great ma.s.ses of conglomerate or shingle, made up of chalk-flints rolled by water. These separate the Chalk from the overlying beds, and many of the rolled flints contain certain petrified _chalk_-fossils. Now, every such fossil proves the following points:--

"1. There was a time when the organic body was alive at the bottom of the sea.

"2. It was afterwards imbedded in the cretaceous deposit.

"3. It became petrified; a very slow process.

"4. The Chalk was, by some change of marine currents, washed away, or degraded, [_i. e._ worn away under the atmosphere by the weather and casualties, a process slow almost beyond description,] and the solid flints and fossils [thus detached from their imbeddings], were rolled into shingles.

"5. Afterwards, these shingles were covered up, and buried under Tertiary deposits.

"In this way of interpretation, a section of _a few perpendicular feet_ indicates a LONG lapse of time, and the co-ordinate fact of the entire change of organic types, between the beds above and those below, falls in with the preceding inference, and shows the lapse of time to have been VERY LONG."[50]

IV.

THE CROSS-EXAMINATION.

"When the fact itself cannot be proved, that which comes nearest to the proof of the fact is the proof of the circ.u.mstances that necessarily and usually attend such facts; and _these are called presumptions, and not proofs_, for they stand instead of the proofs of the fact, till the contrary be proved."--GILBERT; LAW OF EVIDENCE.

Such, then, is the evidence for the macro-chronology. I hope I have summed it up fairly; of course, many details I have been forbidden to adduce by want of s.p.a.ce, but they would have been of the same kind as those brought forward. I am not conscious of having in any degree cushioned, or concealed, or understated a single proof which would have helped the conclusion.

A mighty array of evidence it certainly is, and such as appears at first sight to compel our a.s.sent to the sequent claimed for it. I must confess that I have no sympathy with the _reasonings_ of those, however I honour their design, who can find a sufficient cause for these phenomena in the natural operations of the Antediluvian centuries, or in the convulsion that closed them.

But is there no other alternative? Am I compelled to accept the conclusions drawn from the phenomena thus witnessed unto, as undeniable facts, since they refuse to be normally circ.u.mscribed within the limits of the historic period? I verily believe there is another, and a perfectly legitimate solution.

My first business is to examine, and, if I can, to disprove this testimony. If I can show the witness to be liable to error; if I can adduce a principle which invalidates all his proofs; if I can make it undeniably manifest that, in a case precisely parallel, similar conclusions, deduced from exactly a.n.a.logous phenomena, would be notoriously false; if I can do this, I think I have a right to demand that the witness be bowed out of court, as perfectly nugatory and worthless _in this cause_.

In the first place, there is nothing here but _circ.u.mstantial_ evidence; there is no _direct_ testimony to the facts sought to be established.

Let it not seem unfair to make this distinction; it is one of great importance. No witness has deposed to actual observation of the processes above enumerated; no one has appeared in court who declares he actually saw the living _Pterodactyle_ flying about, or heard the winds sighing in the tops of the _Lepidodendra_. You will say, "It is the same thing; we have seen the skeleton of the one, and the crushed trunk of the other, and therefore we are as sure of their past existence as if we had been there at the time." No, it is not the same thing; it is not _quite_ the same thing; NOT QUITE. Strong as is the evidence, it is not _quite_ so strong as if you had actually seen the living things, and had been conscious of the pa.s.sing of time while you saw them live.

It is only by a process of reasoning that you infer they lived at all.[51]

The process is something like this. Here is an object in a ma.s.s of stone, which has a definite form,--the form of the bone of a beast. The more minutely you examine it, the more points of resemblance you find; you say, If this is a bone, it ought to have so and so--condyles, scars for the attachment of muscles in particular spots, a cavity for the reception of marrow, a mark for the insertion of the ligament; you look for each of these, and find all in the very conditions you have prescribed; it is not only a bone, but a particular bone, the thigh-bone, for instance. Here in the same block of stone is another object: you work it out; it is another bone; its joint accurately fits the preceding; it answers precisely to the tibia of a mammal. Other bones at length appear, and you have got a perfect skeleton, no part redundant, none wanting; the most minute, the most elaborate, the most delicate portions of the osseous frame of a mammal are present, and every one exactly correspondent to the rest in size, in maturity, _in fit._ Each bone, out of the scores, displays exactly those characters, and no other, which an anatomist would have said beforehand it ought to have. Allowing for the difference of species, the skeleton, when worked out of its matrix, and set up, is precisely like that of the little beast at whose death you were actually present, whose bones you cleaned with your own hands, and mounted for your own museum. It would be as reasonable to deny that the one is the skeleton of a real animal as the other.

Thus far there is matter of fact--observed, witnessed fact; you have found in a stone a real skeleton.

You immediately infer that this skeleton once belonged to a living animal, that breathed, and fed, and walked about, exactly as animals do now. This conclusion seems so obvious and unavoidable, that we naturally conclude it to rest on the same foundation as the fact that the object _is_ a skeleton, or that _it was_ in the stone. But really it rests on a totally different foundation; it is a conclusion deduced by a process of reasoning from certain a.s.sumed premises.

Myriads, perhaps millions of skeletons of animals like this one have come at different times under human observation, which have been obviously referrible to creatures that, within the same sphere of observation, had been alive. No similar skeleton has ever come within the range of recorded observation that could be referred to any other source than that of a quondam living animal. On these premises you build the conclusion that a skeleton must, at some time or other, have belonged to a living animal. And it may seem an impregnable position; but yet its validity altogether depends on the exhaustive power of human observation. If I could show, to your satisfaction, that a skeleton might have existed; still more, if I could show you that a skeleton _must_ have existed; still more, if I could prove that myriads of skeletons, precisely like this, must have existed, without ever having formed parts of antecedent living bodies; you would yourself acknowledge that your conclusions were untenable. The utmost you could affirm, would be, that possibly, perhaps probably, the skeleton you had found in the stone had at some time belonged to a living animal, but that, so far as any recognised premises exist, there was no certainty about it.

But the premises have not been fairly stated. There is more than the relation of precedence and sequence in what we know of the connexion between skeletons and living animals; there is the relation of cause and effect. It is not only that universal experience has declared the _fact_ that every skeleton was once part of a living body; it has shown that the very structure and nature of the skeleton _implied_ living body. The skeleton, in every part, displays a regard for the advantages of the living animal; it is built expressly for it; by itself it is nothing--a machine without any object; its joints, its cavities, its apophyses, its processes, all have special reference to tissues and organs which are not here now, but which belong to the living body.

And then experience has shown that the skeleton is made in a particular manner. The bone is deposited, atom by atom, in living organic cells, which are formed by living blood, which implies a living animal. The microscopic texture of your stone-girt skeleton does not differ from that of the skeleton which you cleaned from the muscles with your own hands; and therefore you infer that it was constructed in the same way, namely, by the blood of a living body.

Well, I come back, notwithstanding, to my position,--that your right to _affirm_ this must altogether depend on the exhaustive power of that experience on which you build. And it will be overthrown, if I can show that skeletons have been made in some other way than by the agency of living blood.

Can I do this? I think I can. At least I think I can show enough greatly to diminish, if not altogether to destroy, the confidence with which you inferred the existence of vast periods of past time from geological phenomena. I can adduce a principle, having the universality (within its proper sphere) of LAW, hitherto unrecognised, whose tendency is to invalidate the testimony of your witness.

V.

POSTULATES.

"A little philosophy inclineth a man's mind to atheism; but depth in philosophy bringeth men's minds about to religion; for while the mind of man looketh upon second causes scattered, it may sometimes rest in them, and go no farther; but when it beholdeth the chain of them confederate and linked together, it must needs fly to Providence and Deity."--BACON.

"'What was the opinion of Pythagoras concerning wildfowl?'

'That the soul of our grand-dam might haply inhabit a bird.'

'What thinkest thou of his opinion?'

'I think n.o.bly of the soul, and in nowise receive his opinion.'"

SHAKSPEARE.

As without some common ground it is impossible to reason, I shall take for granted the two following principles:--

I. THE CREATION OF MATTER.

II. THE PERSISTENCE OF SPECIES.

I. If any geologist take the position of the necessary eternity of matter, dispensing with a Creator, on the old ground, _ex nihilo nihil fit_,--I do not argue with him. I a.s.sume that at some period or other in past eternity there existed nothing but the Eternal G.o.d, and that He called the universe into being out of nothing.