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tains, were the first that appeared; the plains soon after came forward, and at length the whole globe was delivered from the waters, except the places in the lowest situations; so that the ocean and the seas are still a part of the ancient abyss, that have not had a place to return. Islands and rocks are fragments of the earth's former crust, kingdoms and continents are larger masses of its broken substance; and all the inequalities that are to be found on the surface of the present earth, are owing to the accidental confusion into which both earth and waters were then thrown."

the middle of our globe a hard solid body; those | its broken surface, now become the tops of mounof a lighter nature remained next; and the waters, which were lighter still, swam upon its surface, and covered the earth on every side. The air, and all those fluids which were lighter than water, floated upon this also; and in the same manner encompassed the globe; so that between the surrounding body of waters, and the circumambient air, there was formed a coat of oil, and other unctuous substances, lighter than water. However, as the air was still extremely impure, and must have carried up with it many of those earthy particles with which it once was intimately blended, it soon began to defecate, and to depose these particles upon the oily surface already mentioned, which soon uniting, the earth and oil formed that crust, which soon became a habitable surface, giving life to vegetation, and dwelling to animals.

It

The next theorist was Woodward, who, in his Essay towards a Natural History of the Earth, which was only designed to precede a greater work, has endeavoured to give a more rational account of its appearances; and was, in fact, much better furnished for such an undertaking than any of his predecessors, being one of the most assiduous naturalists of his time. His little

relative to natural history, although his system may be weak and groundless.

He begins by asserting that all terrene substances are disposed in beds of various natures, lying horizontally one over the other, somewhat like the coats of an onion; that they are replete with shells, and other productions of the sea; these shells being found in the deepest cavities, and on the tops of the highest mountains. From these observations, which are warranted by ex

"This imaginary antediluvian abode was very different from what we see it at present. The earth was light and rich, and formed of a sub-book, therefore, contains many important facts, stance entirely adapted to the feeble state of incipient vegetation; it was a uniform plain, everywhere covered with verdure; without mountains, without seas, or the smallest inequalities. had no difference of seasons, for its equator was in the plane of the ecliptic, or, in other words, it turned directly opposite to the sun, so that it enjoyed one perpetual and luxuriant spring. However, this delightful face of nature did not long continue in the same state; for, after a time, it began to crack and open in fissures; a circum-perience, he proceeds to observe, that these stance which always succeeds when the sun ex- shells and extraneous fossils are not productions hales the moisture from rich or marshy situa- of the earth, but are all actual remains of those tions. The crimes of mankind had been for some animals which they are known to resemble; that time preparing to draw down the wrath of Hea- all the beds of the earth lie under each other, in 7en; and they, at length, induced the Deity to the order of their specific gravity; and that they defer repairing these breaches in nature. Thus are disposed as if they had been left there by subthe chasms of the earth every day became wider, siding waters. All these assertions he affirms and, at length, they penetrated to the great with much earnestness, although daily experiabyss of waters; and the whole earth, in a man- ence contradicts him in some of them; parner, fell in Then ensued a total disorder in the ticularly we find layers of stone often over the uniform beauty of the first creation, the terrene lightest soils, and the softest earth under the surface of the globe being broken down as it hardest bodies. However, having taken it for sunk the waters gushed out in its place; the granted, that all the layers of the earth are deluge became universal; all mankind, except found in the order of their specific gravity, the eight persons, were destroyed, and their poster-lightest at the top, and the heaviest next the ity condemned to toil upon the ruins of deso- centre, he consequently asserts, and it will not imlated nature."

probably follow, that all the substances of which the earth is composed, were once in an actual state of dissolution. This universal dissolution he takes to have happened at the time of the flood. He supposes, that at that time a body of water which was then in the centre of the earth,

It only remains to mention the manner in which he relieves the earth from this universal wreck, which would seem to be as difficult as even its first formation. "These great masses of earth falling into the abyss, drew down with them vast quantities also of air; and, by dash-uniting with that which was found on the suring against each other, and breaking into small parts by the repeated violence of the shock, they at length left between them large cavities, filled with nothing but air. These cavities naturally offered a bed to receive the influent waters; and in proportion as they filled, the face of the earth became once more visible. The higher parts of

face, so far separated the terrene parts as to mix all together in one fluid mass; the contents of which afterwards sinking according to their respective gravities, produced the present ap pearances of the earth. Being aware, however, of an objection, that fossil substances are not found dissolved, he exempts them from this

universal dissolution, and, for that purpose, the heavy first-descending parts in the same endeavours to show that the parts of animals manner as these surround the central globe. have a stronger cohesion than those of minerals; and that, while even the hardest rocks may be dissolved, bones and shells may still continue entire.

The whole economy of the creation being thus adjusted, it only remained to account for the risings and depressions on the surface of the earth, with the other seeming irregularities of its present appearance. The hills and valleys are considered by him as formed by their pressing upon the internal fluid, which sustains the outward | shell of earth, with greater or less weight: those parts of the earth which are heaviest sink into the subjacent fluid more deeply, and become valleys: those that are lightest rise higher upon the earth's surface, and are called mountains.

Thus the entire body of the earth is composed internally of a great burning globe: next which is placed a heavy terrene substance, that encompasses it; round which is also circumfused a So much for Woodward; but of all the sys- body of water. Upon this body of water, the tems which were published respecting the earth's crust of earth, which we inhabit, is placed: so formation, that of Whiston was most applauded, that, according to him, the globe is composed of and most opposed. Nor need we wonder: for a number of coats, or shells, one within the other, being supported with all the parade of deep cal- all of different densities. The body of the earth culation, it awed the ignorant, and produced the being thus formed, the air, which is the lightest approbation of such as would be thought other substance of all, surrounded its surface; and the wise; as it implied a knowledge of abstruse beams of the sun, darting through, produced that learning, to be even thought capable of compre-light which, we are told, first obeyed the Creahending what the writer aimed at. In fact, it is tor's command. not easy to divest this theory of its mathematical garb; but those who have had leisure, have found the result of our philosopher's reasoning to be thus: He supposes the earth to have been originally a comet; and he considers the history of the creation, as given us in Scripture, to have its commencement just when it was, by the hand of the Creator, more regularly placed as a planet in our solar system. Before that time he supposes it to have been a globe without beauty or proportion; a world in disorder; subject to all the vicissitudes which comets endure; some of which have been found, at different times, a Such was the face of nature before the deluge: thousand times hotter than melted iron; at the earth was then more fertile and populous others, a thousand times colder than ice. These than it is at present; the life of man and anialternations of heat and cold, continually melt-mals was extended to ten times its present duing and freezing the surface of the earth, he sup-ration; and all these advantages arose from the poses to have produced, to a certain depth, a chaos entirely resembling that described by the poets, surrounding the solid contents of the earth, which still continued unchanged in the midst, making a great burning globe of more than two thousand leagues in diameter. This surrounding chaos, however, was far from being solid: he resembles it to a dense, though fluid atmosphere, composed of substances mingled, agitated, and shocked against each other; and in this disorder he describes the earth to have been just at the eve of creation.

But upon its orbit being then changed, when it was more regularly wheeled round the sun, every thing took its proper place; every part of the surrounding fluid then fell into a situation, in proportion as it was light or heavy. The middle, or central part, which always remained unchanged, still continued so, retaining a part of that heat which it received in its primeval approaches towards the sun; which heat, he calculates, may continue for about six thousand years. Next to this fell the heavier parts of the chaotic atmosphere, which serve to sustain the lighter but as in descending they could not entirely be separated from many watery parts, with which they were intimately mixed, they drew down a part of these also with them; and these could not mount again after the surface of the earth was consolidated: they, therefore, surrounded

:

superior heat of the central globe, which ever since has been cooling. As its heat was then in full power, the genial principle was also much greater than at present; vegetation and animal increase were carried on with more vigour; and all nature seemed teeming with the seeds of life. But these physical advantages were only productive of moral evil: the warmth which invigorated the body increased the passions and appetites of the mind; and, as man became more powerful, he grew less innocent. It was found necessary to punish this depravity; and all living creatures were overwhelmed by the deluge in universal destruction.

This deluge, which simple believers are willing to ascribe to a miracle, philosophers have long been desirous to account for by natural causes; they have proved that the earth could never supply from any reservoir towards its centre, nor the atmosphere by any discharge from above, such a quantity of water as would cover the surface of the globe to a certain depth over the tops of our highest mountains. Where, therefore, was all this water to be found? Whiston. has . found enough, and more than a sufficiency, in the tail of a comet; for he seems to allot comets a very active part in the great operations of nature.

He calculates, with great seeming precision, the year, the month, and the day of the week, on which this comet (which has paid the earth

some visits since, though at a kinder distance) | would continue to recede from it for ever, were involved our globe in its tail. The tail he supposed to be a vaporous fluid substance, exhaled from the body of the comet by the extreme heat of the sun, and increasing in proportion as it approached that great luminary. It was in this that our globe was involved at the time of the deluge; and, as the earth still acted by its natural attraction, it drew to itself all the watery vapours which were in the comet's tail; and the internal waters being also at the same time let loose, in a very short space the tops of the highest mountains were laid under the deep.

The punishment of the deluge being thus completed, and all the guilty destroyed, the earth, which had been broken by the eruption of the internal waters, was also enlarged by it; so that, upon the comet's recess, there was found room sufficient in the internal abyss for the recess of the superfluous waters; whither they all retired, and left the earth uncovered, but in some respects changed, particularly in its figure, which, from being round, was now become oblate. In this universal wreck of nature, Noah survived, by a variety of happy causes, to repeople the earth, and to give birth to a race of men slow in believing ill-imagined theories of the earth.

After so many theories of the earth which had been published, applauded, answered, and forgotten, Mr. Buffon ventured to add one more to the number. This philosopher was, in every respect, better qualified than any of his predecessors for such an attempt, being furnished with more materials, having a brighter imagination to find new proofs, and a better style to clothe them in. However, if one so ill-qualified as I am may judge, this seems the weakest part of his admirable work; and I could wish that he had been content with giving us facts instead of systems; that, instead of being a reasoner, he had contented himself with being merely an historian.

He begins his system by making a distinction between the first part of it and the last; the one being founded only on conjecture, the other depending entirely upon actual observation. The latter part of his theory may, therefore, be true, though the former should be found erroneous.

"The planets,” says he, “and the earth among the number, might have been formerly (he only offers this as conjecture) a part of the body of the sun, and adherent to its substance. In this situation, a comet falling in upon that great body might have given it such a shock, and so shaken its whole frame, that some of its particles might have been driven off like streaming sparkles from red-hot iron; and each of these streams of fire, small as they were in comparison of the sun, might have been large enough to have made an earth as great, nay, many times greater, than ours. So that in this manner the planets, together with the globe which we inhabit, might have been driven off from the body of the sun by an impulsive force: in this manner also they

they not drawn back by its superior power of attraction; and thus, by the combination of the two motions, they are wheeled round in circles. "Being in this manner detached at a distance from the body of the sun, the planets, from having been at first globes of liquid fire, gradually became cool. The earth also, having been impelled obliquely forward, received a rotatory motion upon its axis at the very instant of its formation; and this motion being greatest at the equator, the parts there acting against the force of gravity, they must have swollen out, and given the earth an oblate or flattened figure.

"As to its internal substance, our globe, having once belonged to the sun, it continues to be an uniform mass of melted matter, very probably vitrified in its primeval fusion. But its surface is very differently composed. Having been in the beginning heated to a degree equal to, if not greater, than what comets are found to sustain; like them it had an atmosphere of vapours floating round it, and which, cooling by degrees, condensed and subsided upon its surface. These vapours formed, according to their different densities, the earth, the water, and the air; the heavier parts falling first, and the lighter remaining still suspended."

Thus far our philosopher is, at least, as much a system-maker as Whiston or Burnet; and, indeed, he fights his way with great perseverance and ingenuity, through a thousand objections that naturally arise. Having, at last, got upon the earth, he supposes himself on firmer ground, and goes forward with greater security. Turning his attention to the present appearance of things upon this globe, he pronounces from the view, that the whole earth was at first under water. This water he supposes to have been the lighter parts of its former evaporation, which, while the earthy particles sunk downwards by their natural gravity, floated on the surface, and covered it for a considerable space of time. "must

"The surface of the earth," says he,3 have been in the beginning much less solid than it is at present; and, consequently, the same causes which at this day produce but very slight changes, must then, upon so complying a substance, have had very considerable effects. We have no reason to doubt but that it was then covered with the waters of the sea; and that those waters were above the tops of our highest mountains; since, even in such elevated situations, we find shells and other marine productions in very great abundance. It appears also that the sea continued for a considerable time upon the face of the earth: for as these layers of shells are found so very frequent at such great depths, and in such prodigious quantities, it seems impossible for such numbers to have been supported all alive at one time; so that

3 Theorie de la Terre, vol. i. p. 111.

they must have been brought there by successive | Hutton supposes this globe to be regulated by a depositions. These shells also are found in the system of decay and renovation, and that these are bodies of the hardest rocks, where they could relation to each other. effected by certain processes which bear a uniform | The solid matter of the not have been deposited, all at, once, at the time earth, especially the rocks and high lands, he sup of the deluge, or at any such instant revolution; poses to be perpetually separating, by the reiterated since that would be to suppose, that all the rocks action of air and water, and when thus detached, in which they are found, were, at that instant, in the beds of the ocean. carried down by the streams and rivers and deposited From these deposites, in a state of dissolution, which would be absurd the various strata of our earth are supposed to be to assert. The sea, therefore, deposited them formed, obtaining their consolidation from the action wheresoever they are now to be found, and that of submarine fires; which being placed at immense by slow and successive degrees. depths, must operate on these stratified depositions under the circumstance of vast pressure, by which volatilization must be prevented, and such changes produced as would not otherwise be effected by the power of heat. The expansive power of subterraneous fire is also called into explain, by the elevation of strata, their various positions. Thus, whilst the ocean is in one part removed by the accumulation and the elevation of strata, fresh receptacles are forming for it in other spots, where new strata will be deposited, consolidated, and elevated. According which is made up of the fragments of those which to this system, therefore, in the present world— preceded it—the materials are arranging for the formation of a new surface; new worlds are rising at the bottom of the present oceans; and imagination pictures successive lands overwhelmed by successive oceans, and these in turn producing new kingdoms, to be peopled by new nations; the system manifesting, as its author avowed, neither vestige of a beginning, nor prospect of an end.

"It will appear also, that the sea covered the whole earth, from the appearance of its layers, which lying regularly one above the other, seem all to resemble the sediment formed at different times by the ocean. Hence, by the irregular force of its waves, and its currents driving the bottom into sand-banks, mountains must have been gradually formed within this universal covering of waters; and these successively raising their heads above its surface, must, in time, have formed the highest ridges of mountains upon land, together with continents, islands, and low grounds, all in their turns. This opinion will receive additional weight by considering, that in those parts of the earth where the power of the ocean is greatest, the inequalities on the surface of the earth are highest. The ocean's power is greatest at the equator, where its winds and tides are most constant; and, in fact, the mountains at the equator are found to be higher than in any other part of the world. The sea, therefore, has produced the principal changes in our earth; rivers, volcanoes, earthquakes, storms, and rain, having made but slight alterations, and only such as have affected the globe to very inconsiderable depths."

This is but a very slight sketch of Mr. Buffon's theory of the earth; a theory which he has much more powerfully supported than happily invented; and it would be needless to take up the reader's time from the pursuit of truth in the discussion of plausibilities. In fact, a thousand questions might be asked this most ingenious philosopher, which he would not find it easy to answer; but such is the lot of humanity, that a single Goth can in one day destroy the fabric which Caesars were employed an age in erecting. We might ask, how mountains, which are composed of the most compact and ponderous substances, should be the first whose parts the sea began to remove? We might ask, how fossilwood is found deeper even than shells? which argues, that trees grew upon the places he supposes once to have been covered with the ocean. But we hope this excellent man is better employed than to think of gratifying the petulance of incredulity, by answering endless objections.

"NOTE.-Geological Theories.

Since Goldsmith wrote, various other theories of the earth have been advanced, the most important of which are the Huttonian and Wernerian. Dr.

existed originally in a state of aqueous fluidity, which
According to Werner the earth is supposed to have
is inferred from its spheroidical form, and from the |
highest mountains being composed of rocks, possess-
ing a structure exactly resembling that of those
fossils, which have, as it were, been formed under
follows, that the ocean must have formerly stood
the eye by water. From this circumstance it also
very high over these mountains; and as these appear
to have been formed during the same period of time,
it follows, that the ocean must have formerly covered
the whole earth at the same time. Contemplating
the formation of the mountains themselves, Werner
discovered the strongest proof of the diminution of
the original waters of the globe. He ascertained, 1st,
That the outgoings-that is, the upper extremities
as they appear at the surface of the earth of the
newer strata are generally lower than the outgoings
of the older, from granite downwards to the alluvial
deposite-and that not in particular spots, but around
the whole globe. 2d, That the primitive part of the
earth is entirely composed of chemical precipitations,
and that the mechanical depositions only appear in
those of a later period, that is, in the transition class;
and continue increasing through all the succeeding
classes of rocks. This evidence of the vast diminu-
tion of water which stood so high over the whole
though we can form no correct idea of what has
earth, is assumed to be perfectly satisfactory, al-
become of it. By the earliest separations from the
chaotic mass which are discoverable in the crust of
the globe, was formed a class of rocks, which are
which mark the high antiquity of these rocks are,
therefore termed primitive rocks. The circumstances
that they form the fundamental rock of the other
classes. Having been formed in the uninhabitable
state of the globe, they contain no petrifactions, and,
excepting the small portion which sometimes accom-
pany those which will be next mentioned, they con-
tain no mechanical deposites, but are, throughout,
pure chemical productions. Small portions of car-
bonaceous matter occur only in the newer members
of the class. Before the summits of the mountains
appeared above the level of the ocean, and before
the creation of vegetables and animals, a rising of

the waters is supposed to have taken place, during | fragments of ores, and different kinds of precious which, that class of rocks which are said to be of the second formation was deposited. The rocks of this formation are clay, porphyry, pearl stone porphyry, obsidian porphyry, sienite, and pitchstone; they exhibit very few mechanical depositions, are of complete chemical formation, and contain little or no carbonaceous matter, and never any petrifactions. On the appearance of land, or during the transition of the earth from its chaotic to its habitable state, rocks which from this circumstance are denominated transition rocks were formed. In these rocks, the first slight traces of petrifaction, and of mechanical depositions, are to be found. As the former class of rocks were purely of chemical formation, so the contents of these are chiefly chemical productions, mingled with a small proportion of mechanical depositions; to explain the cause of the mixture, we are referred to the period of their formation, that at which the summits of the primitive mountains just appeared above the waters, when, by the attraction excited by the motion of the waves, and which we are reminded extended to no great depth, particles of the original mountains were worn off and deposited. As the height of the level of the ocean diminished, so would the surface on which its waves acted increase, and of course the number of mechanical depositions. Hence, these are much more abundant in the rocks of the next formation, which are denominated floetz rocks, on account of their being generally disposed in horizontal or flat strata. In these, petrifactions are very abundantly found, having been formed whilst vegetables and animals existed in great numbers. These rocks are generally of very wide extent, and commonly placed at the foot of primitive mountains; they are seldom of a very great height, from whence it may be inferred, that the water had considerably subsided at the time of their formation, and did not then cover the whole face of the earth. Countries composed of these rocks are not so rugged in their appearance, nor so marked by sudden inequalities, as those in which the primitive and transition rocks prevail. Most of the rocks which have been just enumerated, are covered by a great formation, which is named the newest floetz trap. This formation also covers many of the highest primitive mountains; it has but little continuity, but is very widely distributed. It contains considerable quantities of mechanical deposites, such as clay, sand, and gravel. The remains both of vegetables and animals also occur very abundantly in these deposites. Heaps of trees, and parts of plants, and an abundance of shells and other marine productions, with the horns of stags, and great beds of bituminous fossils, point out the lateness of the period when this formation was deposited. In this formation several rocks occur which are also met with in other floetz formations; but the following are supposed to be peculiar to this class: basalt, wacke, greystone, porphyry, slate, and trap tuff. These rocks are said to have been formed during the settling of the water consequent upon a vast deluge, which is supposed to have taken place when the surface of the earth was covered with animals and vegetables, and when much dry land existed. From various appearances observed in these rocks, it is concluded, that the waters in which they were formed had risen with great rapidity, and had afterwards settled into a state of considerable calmness. The collections and deposites derived from the materials of pre-existing masses, worn down by the powerful agency of air and water, and afterwards deposited on the land, or on the sea-coast, are termed alluvial, and are, of course, of much later formation than any of the preceding classes. These deposites may be divided into: 1st, Those which are formed in mountainous countries, and are found in valleys, being composed of rolled masses, gravel, sand, and sometimes loam,

stones. 2d, Those which occur in low and flat countries, being peat, sand, loam, bog, iron ore, nagelflech, calc-tuff and calc-sinter; the three latter being better known by the names breccia, tufa, and stalactite.

Every part of the surface of this globe, M. Cuvier maintains, exhibits such phenomena, as unavoidably lead to the conclusion that the sea, at one period or another, has covered the whole, and remained for a long time in a state of tranquillity so as to form those regular and extensive horizontal deposites in which many of the marine exuviæ are contained. But there are also inclined or vertical strata of the same nature, situated under the horizontal strata, which having been necessarily formed in a horizontal position, have been subsequently lifted up and shifted into their inclined or vertical situation, and that too before the horizontal strata were deposited above them. Now 1 amid these changes it was hardly possible that the same species of animals should continue to live. There must have been a succession of changes in animal natures corresponding to that in the chemical properties of the fluid which they inhabited. It is also conceivable that the change of element might be so great as to cause the entire destruction of all existing genera. Accordingly, not only the species, but even the genera, change with the strata; and when the sea last receded from our continent, its inhabitants were not very different from those which it continues to support. The strata around us, therefore, may serve the double purpose of recording the great revolutions which have taken place both in the animal kingdom and upon the surface of the globe. Neither physical nor astronomical causes of revolution on the earth's surface are sufficient to explain these changes. The irruption of the sea and its retreat have neither been slow nor gradual; the catastrophes have been sudden, and the present surface of the world is by no means of very ancient formation. This theory approximates more nearly to the Mosaical record than many others which we have noticed. In fact, modern geologists are all eager to bear testimony to the actual occurrence of the deluge.

CHAP. V.

OF FOSSIL-SHELLS, AND OTHER EXTRANEOUS
FOSSILS.

We may affirm of Mr. Buffon, that which has
been said of the chemists of old; though he may
have failed in attaining his principal aim, of estab-
lishing a theory, yet he has brought together
such a multitude of facts relative to the history
of the earth, and the nature of its fossil produc-
tions, that curiosity finds ample compensation,
even while it feels the want of conviction.

Before, therefore, I enter upon the description of those parts of the earth which seem more naturally to fall within the subject, it will not be improper to give a short history of those animal productions that are found in such quantities, either upon its surface, or at different depths below it. They demand our curiosity; and, indeed, there is nothing in natural history that has afforded more scope for doubt, conWhatever depths of jecture, and speculation. the earth we examine, or at whatever distance

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