astronomy and geography, one of the primary planets; being this terraqueous globe which we inhabit.

The cosmogony, or knowledge of the original formation of the earth, the materials of which it was composed, and by what means they were disposed in the order in which we see them at present, is a subject which, though perhaps above the reach of human capacity, has exercised the wit of philosophers in all ages. To recount the opinions of all the eminent philosophers of antiquity upon this subject would be very tedious: it may therefore suffice to observe, that, ever since the subject began to be canvassed, the opinions of those who have treated it may be divided into two classes. 1. Those who believed the earth and whole visible system of nature to be the Deity himself, or connected with him in the same manner that a human body is with its soul. 2. Those who believed the materials of it to have been eternal, but distinct from the Deity, and put into the present order by some power either inherent in themselves or belonging to the Deity. Of the former opinion were Zenophanes the founder of the eleatic sect, Strato of Lampacus, the Peripatetics, &c.

The second opinion, namely, that the substance of the earth or universe (for it is impossible to speak of the one without the other) was eternal, though not the form, was most generally held among the ancients. From that established axiom, that "nothing can be produced from nothing," they concluded that creation was an impossibility; but at the same time they thought they had good reason to believe the world had not been always in its present form. They who held this opinion may again be divided into two classes: first, those who endeavoured to account for the generation of the world, or its reduction into the present form, by principles merely mechanical, without having recourse to any assistance from divine power; and, secondly, those who introduced an intelligent mind as the author and disposer of all things. To the first of these classes belonged the cosmogony of the Babylonians, Phoenicians, and Egyptians; the particulars of which are too absurd to deserve notice. Of the same opinion also were most of the poets; the philosophers Thales, Anaximander, Anaximenes, Anaxagoras, &c. The latter attempted to reform the philosophy of his master Anaximenes by introducing an intelligent principle into the world distinct from matter; thus making his intelligent principle, or God, the soul of the world. Diogenes of Apollonia supposed air, which he made the first principle of all things, to be ended with reason: His manner of philosophising differed very little from that of Descartes. "All things (says he) being in motion, some became condensed and others rarefied. In those places where condensation prevailed, a whirling motion or vortex was formed; which by its revolution drew in the rest, and the lighter parts flying upwards formed the sun."

The most remarkable of the atheistic systems, however, was the atomic one, supposed to have been invented by Democritus; though Laertius attributes it to Leucippus, and some make it much older. According to this system, the first principles of all things were an infinite multitude of atoms, or indivisible particles of different sizes and figures; which, moving fortuitously, or without design, from all eternity, in infinite space, and encountering with one another, became variously entangled during their conflict. This first produced a confused chaos of all kinds of particles; which afterwards, by continual agitation, striking and repelling each other, disposed themselves into a vortex or vortices, where, after innumerable revolutions and motions in all possible directions, they at last settled into their present order.

The hypothesis of Democritus agrees in the main with that of Epicurus as represented by Lucretius; excepting that no mention is made of those vortices, which yet were an essential part of the former. To the two properties of magnitude and figure which Democritus attributed to his atoms, Epicurus added a third, namely, weight; and, without this, he did not imagine they could move at all. The system of Democritus necessarily introduced absolute fatal necessity; which Epicurus not choosing to agree to, he invented a third motion of the atoms, unknown to those who had gone before him. His predecessors allowed them to have a perpendicular and reflexive motion: but, Epicurus, though he allowed these motions to be absolutely necessary and unavoidable, asserted that the atoms could also of themselves decline from the right line: and from this declination of the atom he explained the free will of man.—The most material difference between the two systems, however, was, that Epicurus admitted no principle but the atoms themselves; whereas Democritus believed them to be animated.

Of those who held two distinct and coeternal principles, viz. God and Matter, we shall only take notice of the opinions of Pythagoras, Plato, and Aristotle, as to, and being the most remarkable.

Pythagoras is said to have asserted two substantial self-existent principles: a monad, or unity; and a dyad, or duality. The meaning of these terms is now somewhat uncertain. Some think, that by the monad he meant the Deity, and by the dyad matter. Others think, that the Pythagorean monads were atoms. The dyad is sometimes thought to signify a demon or evil principle; but Porphyry's interpretation, which seems the most probable, is as follows. The cause, says he, of that sympathy, harmony, and agreement which is in things, and of the conservation of the whole, which is always the same and like itself, was by Pythagoras called unity; that unity which is in the things themselves being but a participation of the first cause: but the reason of difference, inequality, and constant irregularity in things, was by him called a dyad. This philosopher held numbers to be the principles... principles of all things; and from them he accounted for the production of the world in the following manner. He supposed that the monad and dyad were the two sources of numbers, from whence proceeded points; from points, lines; from lines, plane figures; from planes, solids; from solids, sensible bodies. The elements of sensible bodies are four; but, besides these, there was a fifth (never yet discovered). The four elements which manifest themselves to our senses are, fire, air, earth, and water. These are in a perpetual change, and from them the world was formed; which is animated, intelligent, and spherical; containing, in the midst of it, the earth, a globe or inhabited body. The world, he said, began from fire and the fifth element; and that as there were five figures of solid bodies, called mathematical or regular, the earth was made of the cube, fire of the pyramid or tetrahedron, the air of the octahedron, water of the icosahedron, and the sphere of the universe of the dodecahedron.

This method of philosophizing, which has no manner of foundation in nature, was adopted by Plato and Aristotle; and hence proceeded all the absurdities concerning ideas, forms, qualities, &c., with which the Aristotelian philosophy was loaded.

For a long time, however, the philosophy of Aristotle prevailed, and the world was thought to be upheld by forms, qualities, and other unintelligible and imaginary beings. At last the French philosopher Descartes superseded the Aristotelian, by introducing the atomic or Democritic, and Epicurean philosophy*. The Cartesian system was quickly superseded by the Newtonian; which still continues, though considerably different from what it was left by that great man.—His opinions, indeed, concerning the cosmogony seem to have been in a fluctuating state; and hence he delivers himself in such a manner, that he hath often incurred the charge of contradicting himself.—He maintained, for instance, that matter was infinitely divisible; and the mathematical demonstrations of this proposition are well known. Notwithstanding this, however, when he comes particularly to speak of the original construction of the world, he seems to retract this opinion, and adopt the atomic philosophy. He tells us, that it seems probable, that in the beginning God formed matter in solid, malleable, impenetrable particles, &c.; and that of these particles, endowed with various powers of attraction and repulsion, the present system of nature is formed. His primary laws of nature are only three in number, and very simple. The first is, that all matter has a tendency to continue in that state in which it is once placed, whether of rest or motion. If it is at rest, for example, it will continue at rest for ever, without beginning motion of itself; but if it is once set in motion by any cause whatever, it will for ever continue to move in a right line, until something either stops it altogether, or forces it to move in another direction. 2. That the change of motion is always equivalent to the moving force employed to produce it, and in the direction of the right line in which it is impressed; that is, if a certain force produces a certain motion, double that force will produce double that motion, &c. 3. Reaction is always contrary and equal to action; or the actions of two bodies upon one another are always equal and contrary to one another.

Vol. VI. Part I.

From these three laws, together with the two contrary forces of attraction and repulsion, Sir Isaac Newton and his followers have attempted to explain all the phenomena of nature. When they come to explain the nature of the attractive and repulsive forces, however, they are exceedingly embarrassed. Sir Isaac hath expressed himself in two different ways concerning them. In his Principia, he pretty positively determines them to be owing to a cause that is not material; and in his Queries, he supposes they may be effects of some subtile matter which he calls ether. This disagreement with himself hath produced no small disagreement among his followers. One party, laying hold of his mongish assertions in the Principia, determine the world to be upheld by immaterial powers; while the other, neglecting the Principia, and taking notice only of the Queries at the end of the Optics, strenuously maintain, that attraction and repulsion are owing to the action of some exceedingly fine and subtile ether.—The first of these suppositions, it is argued, necessarily involves us in one of the following dilemmas. 1. If the attractive and repulsive forces are not material, they must either be occasioned by spiritual beings, or they must be qualities of matter. If they are occasioned by the action of immaterial beings, these beings must either be created or uncreated. If they are produced by the action of created beings, we run into the supposition of some of the ancient heathens, that the world is governed by demons or subordinate intelligences; and thus may make an easy transition to polytheism. If attraction and repulsion are the immediate action of the Deity himself, we run into the doctrine of making God the soul of the world.—This last hypothesis hath been most strenuously adopted by Mr Baxter in his treatise of the Immateriality of the human Soul. Mr Bofcowich, Mr Mitchell, and Dr Priestley, have likewise adopted the hypothesis of immaterial powers to such a degree, coven, and that, according to them, the whole world consists of nothing else but attractions and repulsions surrounding physical points†. 2. If we suppose the attractive and repulsive powers to be only properties, qualities, or laws, then, as impressed on matter by the Deity, we might as well have been contented with the occult qualities of Aristotle.—If attraction and repulsion are occasioned by the action of mere matter, and all the powers in nature are only material, the charge is incurred of making nature direct itself in such a manner, that there is no occasion for the interposition, or even the existence, of a Deity at all.

Thus we see, the Newtonian cosmogony must incline either to the Platonic and Aristotelian, or to the Atomic or Epicurean; according to the hypothesis we lay down concerning the nature of attraction. Descartes's system was plainly a revival of that of Democritus and Epicurus, with some corrections and improvements. It was farther improved and corrected by Mr Hutchinson, who added to it the authority of Revelation. The created agents he chose in his cosmogony were fire, light, and air. These, we see, have indeed a very considerable share in the operations of nature; but unless we explain the manner in which they operate, our knowledge is not at all increased, and we might as well have been contented with the Newtonian attraction and repulsion, or even the occult qualities of Aristotle. Attempts have indeed been made to solve the phenomena. phenomena of nature, from the action of these three agents, both by Hutchinson himself and many of his followers.—These attempts, however, have always proved unsuccessful. Some phenomena indeed may be explained pretty plausibly from the known action of these three; but when we come to speak of what may be called the nicer operations of nature, such as the growth of plants and animals, we are utterly at a loss.

The manifest deficiency of active principles in all the theories of the earth that have yet been invented, hath occasioned a constant search after others which should be able, by their superior activity, to fill up the blank which necessarily remained in the system.—Pythagoras, Plato, and Aristotle, being unable to account for the formation of the earth from their four elements, called in the affluence of a fifth, which was never yet discovered. Epicurus, finding the motions attributed to his atoms by Democritus to be insufficient, had recourse to an imaginary, and on his own principles impossible, declination of the atoms. Des Cartes, finding the atoms themselves insufficient, asserted that they were not atoms, but might be broken into smaller parts, and thus constitute matter of various degrees of subtlety. The Newtonian philosophers have found Des Cartes's system insufficient; but being greatly distressed in their attempts to solve all the phenomena of nature by mere attraction and repulsion, have been obliged to call in the action of mind to their assistance. The Hutchinsonians were hardly put to it in accounting for everything by the action of fire, light, and air; when luckily the discoveries in electricity came to their assistance. It must be owned, that this fluid does indeed come in like a kind of fifth element, which in many cases appears to be the animating principle of nature. For some time past, almost all the remarkable phenomena in nature have been explained by electricity, or the action of the electric fluid. But unless this action is explained, we are got no farther than we were before. To say that any thing is done by electricity, is not more intelligible than to say that it was done by attraction. If we explain an effect by a material cause, it ought to be done upon mechanical principles. We ought to be sensible how one part of matter acts upon another part in such a manner as to produce the effect we desire to explain. The electrical philosophers, however, have not yet been able to investigate the manner in which this subtle fluid operates; and hence the many discoveries in electricity have not contributed to throw that light on the theory of the earth, which perhaps they may do hereafter. With some philosophers, however, the electric fluid itself, and indeed all the powers of nature, were in danger of being superseded by a principle, lately very little known, called the phlogiston.—Thus, Mr. Henly tells us*, that Mr. Clarke, an ingenious gentleman in Ireland, hath discovered all the different kinds of air produced from metals, &c. by Dr. Priestley, to be only phlogistic vapours arising from these substances. Dr. Priestley himself supposes, that the electric light is a modification of phlogiston; and consequently thinks it probable, that all light is a modification of the same. Fire or flame is thought to be a chemical combination of air with the phlogiston; and phlogiston is thought to give the elasticity to air, and every other elastic fluid, &c. Another party, seemingly jealous of the powers of this new principle, have denied its existence altogether, and in its stead introduced another equally insufficient, called the oxygenous principle. Others have reduced all nature to the two principles called principium foribile and principium proprium. All these, however, are shown, in other parts of this work, to be mere inactive substances; the phlogiston, common charcoal; the oxygenous principle, water deprived of the quantity of phlogiston it usually contains; the principium foribile, the same; and the principium proprium, a name for the particular modification of the atoms, or what we please to call the invisible essence of matter which distinguishes one body from another, and which must be for ever unknown to all human creatures.—Be this as it will, the late discoveries in electricity have tended very much to change the form of the Newtonian philosophy, and to introduce that materialism into our theories of the natural phenomena which is by some people so much complained of.

From this general history of the different agents Little pro-which philosophers have chosen to account for the original formation of the earth, and for its preservation in the present form, it appears, that scarce any advance in true knowledge hath yet been made. All the agents have been prodigiously defective; electricity itself, as far as yet known, not excepted. But before we enter into a particular consideration of those theories which appear most worthy of notice, it will be necessary to cur in point out the principal difficulties which stand in the forming a way of one who attempts to give a complete theory of the earth.

1. The earth, although pretty much of a spherical figure, is not completely so; but protuberances considerably about the equatorial parts, and is proportionably flattened at the poles, as is undeniably proved by the observations of modern mathematicians†. The question here is, Why the natural cause which gave the shape of so much of a spherical figure, did not make it a complete and exact sphere?

2. The terraqueous globe consists of a vast quantity of water as well as dry land. In many places, such as the Isthmus of Darien, a narrow neck of land is interposed between two vast oceans. These beat upon it on either side with vast force; yet the Isthmus is never broken down nor diminished. The case is the same with the Isthmus of Suez which joins Asia and Africa, and with that which joins the Morea or ancient Peloponnesus to the continent. The difficulty is, By what natural power or law are these narrow necks of land preserved amidst the waters which threaten them on both sides with destruction?

3. The surface of the earth is by no means smooth and equal; but in some places raised into enormous ridges of mountains, and in others sunk down in such a manner as to form deep valleys. These mountains, though they have been exposed to all the injuries of the weather for many thousand years, exhibit no signs of decay. They still continue of the same size as before, though vast quantities of earth are frequently washed down from them by the rains, which, together with the force of gravity, tending to level and bring them on an equality with the plains on which they stand, we might reasonably think, ought by this time to have rendered them smaller than before. It must therefore therefore be inquired into. By what natural cause the mountains were originally formed, and how they come to preserve their size without any remarkable diminution?

4. The internal parts of the earth are still more wonderful than the external. The utmost industry of man, indeed, can penetrate but a little way into it. As far as we can reach, however, it is found to be composed of dissimilar strata lying one upon another, not commonly in a horizontal direction, but inclined to the horizon at different angles. These strata seem not to be disposed either according to the laws of gravity or according to their density, but as it were by chance. Besides, in the internal parts of the earth are vast chasms and vacuities. By what means were these strata originally deposited, the fissures and chasms made, &c.?

5. In many places of the earth, both on the surface and at great depths under it, vast quantities of marine productions, such as shells, &c. are to be met with. Sometimes these shells are found in the midst of solid rocks of marble and limestone. In the very heart of the hardest stones, also, small vegetable substances, as leaves, &c. are sometimes to be found. The question is, By what means were they brought thither?

There are some of the most striking difficulties which present themselves to one who undertakes to write a natural history or theory of the earth. The most remarkable attempts to produce a theory of this kind are the following.

I. According to Dr Burnet, the earth was originally a fluid mass, or chaos, composed of various substances differing both in density and figure. Those which were most heavy, sunk to the centre, and formed there a hard solid body; those which were specifically lighter remained next above; and the waters, which were lightest of all, covered the earth all round. The air, and other ethereal fluids, which are still lighter than water, floated above it, and surrounded the globe also. Between the waters, however, and the circumambient air, was formed a coat of oily and unctuous matter lighter than water. The air at first was very impure, and must necessarily have carried up with it many of those earthly particles with which it was once blended: however, it soon began to purify itself, and deposit those particles upon the oily crust above mentioned; which, soon uniting together, the earth and oil became the crust of vegetable earth, with which the whole globe is now covered. His account of the destruction of the primeval world by the flood, by the falling down of the shell of earth into the waters of the abyss, is given under the article Deluge. It only remains then to give his account of the manner in which he relieves the earth from this universal destruction; and this he does as follows. These great masses of earth, says he, falling into the abyss, drew down with them vast quantities also of air; and by dashing 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 its broken surface, now become the tops of mountains, 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 seas are still a part of the ancient abyss, that have had no place to which they might return. Islands and rocks are fragments of the earth's former crust; 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 effects of the confusion into which both earth and water were at that time thrown.

II. Dr Woodward begins with asserting, that all terrestrial substances are disposed in beds of various natures, ward's 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 experience, he proceeds to observe, that these shells and extraneous fossils are not productions of the earth, but are all actual remains of those animals which they are known to resemble; that all the strata or beds of the earth lie under each other in the order of their specific gravity, and that they are disposed as if they had been left there by subsiding waters. All this he very confidently affirms, tho' daily experience contradicts him in some of them; particularly, we often find layers of stone over the lightest foils, and the softest earth under the hardest bodies. However, having taken it for granted, that all the layers of the earth are found in the order of their specific gravity, the lightest at top, and the heaviest next the centre, he consequently affirms, that all the substances of which the earth is composed were originally in a state of dissolution. This dissolution he supposes to have taken place at the flood: but being aware of an objection, that the shells, &c. supposed to have been deposited at the flood are not dissolved, he exempts them from the solvent power of the waters, and endeavours to show that they have a stronger cohesion than minerals; and that, while even the hardest rocks are dissolved, bones and shells may remain entire.

III. Mr Whitton supposes the earth to have been originally a comet; and considers the Mosaic account of the creation as commencing at the time when the Creator placed this comet in a more regular manner, and made it a planet in the 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; which, according to the present system of philosophy, must be alternately exposed to the extremes of heat and cold. These alternations of heat and cold, continually melting and freezing the surface of the earth, he supposes to have produced, to a certain depth, a chaos 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 2000 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 supposes the earth to have been just at the eve of the Mosaic 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. fell into a certain situation according 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 about 6000 years. Next to this fell the heavier parts of the chaotic atmosphere, which serve to sustain the lighter: but as in defending they could not entirely be separated from many watery parts, with which they were intimately mixed, they drew down the fire along with them; and these could not mount again after the surface of the earth was consolidated: they therefore surrounded the heavy first-defending parts in the same manner as these surrounded the central globe. Thus the entire body of the earth is composed next the centre of a great burning globe: next this is placed an heavy terrene substance that encompasses it; round which is circumfused a body of water. Upon this body of water is placed the crust of earth on which we inhabit: so that, according to Mr Whitton, the globe is composed of a number of coats or shells, one within the other, all of different densities. The body of the earth being thus formed, the air, which is the lightest substance of all, surrounded its surface; and the beams of the sun darting through, produced the light, which, we are told by Moses, first obeyed the divine command.

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 by him considered as formed by their pressing upon the internal fluid which sustains the external shell of earth, with greater or less weight: those parts of the earth which are heaviest sink the lowest into the subjacent fluid, and thus become valleys: those that are lightest rise higher upon the earth's surface, and are called mountains.

Such was the face of nature before the deluge: the earth was then more fertile and populous than it is at present; the life of men and animals was extended to ten times its present duration; and all these advantages arose from the superior heat of the central globe, which has ever since been cooling. As its heat was then in its 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 as these advantages were productive only of moral evil, it was found necessary to destroy all living creatures by a flood; and in what manner this punishment was accomplished, according to Mr Whitton, is particularly taken notice of under the article Deluge.

IV. M. Buffon's theory differs very widely from the foregoing. He begins with attempting to prove, that this world which we inhabit is no more than the ruins of a world. "The surface of this immense globe (says he) exhibits to our observation, heights, depths, plains, seas, marshes, rivers, caverns, gulfs, volcanoes; and on a cursory view, we can discover in the disposition of these objects neither order nor regularity. If we penetrate into the bowels of the earth, we find metals, minerals, stones, bitumens, sands, earths, waters, and matter of every kind, placed as it were by mere accident, and without any apparent design. Upon a nearer and more attentive inspection, we discover sunk mountains, caverns filled up, shattered rocks, whole countries swallowed up, new islands emerged from the ocean, heavy substances placed above light ones, hard bodies inclosed within soft bodies: in a word, we find matter in every form, dry and humid, warm and cold, solid and brittle, blended in a chaos of confusion, which can be compared to nothing but a heap of rubbish, or the ruins of a world."

When taking a particular survey of the external surface of the globe, he begins with the ocean, and the motion communicated to it by the influence of the sun and moon which produces the tides.—"In examining the bottom of the sea (says he), we perceive it to be equally irregular as the surface of the dry land. We discover hills and valleys, plains and hollows, rocks and earths of every kind; we discover likewise, that islands are nothing but the summits of vast mountains, whose foundations are buried in the ocean. We find other mountains whose tops are nearly on a level with the surface of the water; and rapid currents which run contrary to the general movement. These currents sometimes run in the same direction; at other times their motion is retrograde; but they never exceed their natural limits, which seem to be as immutable as those which bound the efforts of land-rivers. On one hand we meet with tempestuous regions, where the winds blow with irresistible fury; where the heavens and the ocean, equally convulsed, are mixed and confounded in the general shock; violent intestine motions, tumultuous swellings, water-spouts, and strange agitations produced by volcanoes, whose mouths, tho' many fathoms below the surface, vomit forth torrents of fire; and push, even to the clouds, a thick vapour, composed of water, sulphur, and bitumen; and dreadful gulps or whirlpools, which seem to attract vessels for no other purpose than to swallow them up. On the other hand we discover vast regions of an opposite nature, always smooth and calm, but equally dangerous to the mariner. To conclude, directing our eyes toward the southern or northern extremities of the globe, we discover huge masses of ice, which, detaching themselves from the polar regions, advance, like floating mountains, to the temperate climates, where they dissolve and vanish from our view. The bottom of the ocean and the shelving sides of rocks produce plentiful crops of plants of many different species: its soil is composed of sand, gravel, rocks, and shells; in some places it is a fine clay, in others a compact earth; and in general, the bottom of the sea has an exact resemblance to the dry land which we inhabit.

"Let us next take a view of the dry land. Upon an attentive observation of this, we will find, that the great chains of mountains lie nearer the equator than the poles; that in the old continent their direction is more from east to west than from south to north; and that, on the contrary, in the new continent they extend more from north to south than from east to west. But what is still more remarkable, the figure and direction of these mountains, which have a most irregular appearance, correspond so wonderfully, that the prominent angles of one mountain are constantly opposite to the concave angles of the neighbouring mountain, and of equal dimensions, whether they be separated by an extensive plain or a small valley. I have further further remarked, that opposite hills are always nearly of the same height; and that mountains generally occupy the middle of continents, islands, and promontories, dividing them by their greatest lengths. I have likewise traced the courses of the principal rivers, and find that their direction is nearly perpendicular to the sea-coasts into which they empty themselves; and that during the greatest part of their courses they follow the direction of the mountains from which they derive their origin. The sea-coasts are generally bordered with rocks of marble and other hard stones; or rather with earth and sand accumulated by the waters of the sea, or brought down and deposited by rivers. In opposite coasts, separated only by small arms of the sea, the different strata or beds of earth are of the same materials. I find that volcanoes never exist but in very high mountains; that a great number of them are entirely extinguished; that some are connected to others by subterranean passages, and their eruptions not unfrequently happen at the same time. There are similar communications between certain lakes and seas. Some rivers suddenly disappear, and seem to precipitate themselves into the bowels of the earth. We likewise find certain Mediterranean or inland seas, that constantly receive from many and great rivers prodigious quantities of water, without any augmentation of their bounds; probably discharging by subterraneous passages all those extraneous supplies. It is likewise easy to distinguish lands which have been long inhabited, from those new countries where the earth appears in a rude state, where the rivers are full of cataracts, where the land is nearly overflowed with water or burnt up with drought, and where every place capable of producing trees is totally covered with wood.

"Proceeding in our examination, we discover that the upper stratum of the earth is universally the same substance: that this substance, from which all animals and vegetables derive their growth and nourishment, is nothing but a composition of the decayed parts of animal and vegetable bodies, reduced into such small particles that their former organic state is not distinguishable. Penetrating a little deeper, we find the real earth, beds of sand, limestone, clay, shells, marble, gravel, chalk, &c. These beds are always parallel to each other, and of the same thickness throughout their whole extent. In neighbouring hills, beds or strata of the same materials are uniformly found at the same levels, though the hills be separated by large and deep valleys. Strata of every kind, even of the most solid rocks, are uniformly divided by perpendicular fissures. Shells, skeletons of fishes, marine plants, &c. are often found in the bowels of the earth, and on the tops of mountains, even at the greatest distances from the sea. These shells, fishes, and plants, are exactly similar to those which exist in the ocean. Petrified shells are to be met with almost everywhere in prodigious quantities: they are not only inclosed in rocks of marble and limestone, as well as in earths and clays, but are actually incorporated and filled with the very substances in which they are inclosed. In fine, I am convinced, from repeated observation, that marbles, limestones, chalks, marbles, clays, sand, and almost all terrestrial substances, wherever situated, are full of shells and other spoils of the ocean."

From these positions, which he lays down as facts, Mr Buffon draws the following conclusions:

1. The changes which the earth has undergone within these last 2000 or 3000 years must be considerable, when compared with the great revolutions that took place in those ages immediately succeeding the creation. The reason he gives for this assertion is, that terrestrial substances could not acquire solidity but by the continued action of gravity: hence the earth must have been originally much softer than it is now, and therefore more apt to be changed by causes which cannot now affect it.

2. It seems an incontrovertible fact, that the dry land which we now inhabit, and even the summits of the highest mountains, were formerly covered with the waters of the sea; for shells and other marine bodies are still found upon the very tops of mountains.

3. The waters of the sea have remained for a long track of time upon the surface; because in many places, such immense banks of shells have been discovered, that it is impossible so great a multitude of animals could exist at the same time.

4. From this circumstance it likewise appears, that although the materials on the surface of the earth were then soft, easily disunited, moved, and transported by the waters, yet these transportation could not be suddenly effected: they must have been gradual and successive, as sea-bodies are sometimes found more than 1000 feet below the surface; and such a thickness of earth or stone could not be accumulated in a short time.

5. It is impossible these effects could be owing to the universal deluge. For though we should suppose that all the shells in the bottom of the ocean should be deposited upon the dry land; yet, besides the difficulty of establishing this supposition, it is plain, that as shells are found incorporated in marble, and in the rocks of the highest mountains, we must suppose these rocks and marbles to have been formed all at the very instant when the deluge took place; and that before this grand revolution, there were neither mountains, nor marbles, nor rocks, nor clays, nor matter of any kind similar to what we are now acquainted with; as they all, with few exceptions, contain shells and other productions of the ocean. Besides, at the time of the universal deluge, the earth must have acquired a considerable degree of solidity, by the action of gravity for more than 16 centuries. During the short time the deluge lasted, therefore, it is impossible that the waters should have overturned and dissolved the whole surface of the earth to the greatest depths.

6. It is certain (for what reason he does not mention), that the waters of the sea have, at some period or other, remained for a succession of ages upon what we now know to be dry land; and consequently that the vast continents of Asia, Europe, Africa, and America, were then the bottom of an immense ocean, complete with everything which the present ocean produces.

7. It is likewise certain, that the different strata of the earth are horizontal and parallel to each other. This parallel situation must therefore be owing to the operation of the waters, which have gradually accumulated the different materials, and given them the same position which the water itself invariably assumes.

8. It is certain that these strata must have been gradually dually formed, and are not the effect of any sudden revolution; because nothing is more frequent than strata composed of heavy materials placed above light ones; which never could have happened if, according to some authors, the whole had been blended and dissolved by the deluge, and afterwards precipitated.

9. No other cause than the motion and sediments of water could possibly produce the regular position of the various strata of which the superficial part of this earth consists. The highest mountains are composed of parallel strata, as well as the lowest valleys. Of course, the formation of mountains cannot be attributed to the shock of earthquakes, or to the eruptions of volcanoes. Such small eminences as have been raised by volcanoes or convulsions of the earth, instead of being composed of parallel strata, are mere masses of weighty materials, blended together in the utmost confusion.

Having now, as he thinks, proved, that the dry and habitable part of the earth has remained for a long time under the waters of the sea, and consequently must have undergone the same changes that now take place at the bottom of the sea, he proceeds to inquire what these changes are.

10. The ocean, since the creation of the world, has been constantly agitated by the tides, occasioned by the action of the sun and moon; and this agitation is greater in the equatorial than in the other parts of the globe, because the action of the sun and moon is there strongest.

11. The earth performs a rapid motion on its axis; and consequently its parts have a centrifugal force, which is also greatest at the equator.

12. From the combined action of the two last mentioned causes, the tides and the motion of the earth, it may be fairly concluded, that although this globe had been originally a perfect sphere, its diurnal motion, and the ebbing and flowing of the tides, must necessarily, in a succession of time, have elevated the equatorial parts, by gradually carrying mud, earth, sand, shells, &c. from other climates, and depositing them at the equator.

13. On this supposition, the greatest inequalities on the surface of the earth ought to be found, and in fact are found, in the neighbourhood of the equator.

14. As the alternate motion of the tides has been constant and regular since the existence of the world, it is natural to think, that, at each tide, the water carries from one place to another a small quantity of matter, which falls to the bottom as a sediment, and forms those horizontal and parallel strata that every where appear. Here it may indeed be objected, that as the flux is equal to, and regularly succeeded by, the reflux, the two contrary motions will balance each other; and whatever is brought in by the flux will be carried back by the reflux. The motion of the ocean, therefore, could never be the cause of the formation even of parallel strata; much less of mountains, and all the inequalities to be observed in this globe. To this Mr Buffon replies, that the alternate motion of the waters is by no means equal; for the sea has a continual motion from east to west; the agitations occasioned by the winds likewise produce great inequalities in the tides. It must also be acknowledged, that, by every motion of the sea, particles of earth and other matter must be carried from one place and deposited in another; and that these collections of matter must assume the form of parallel and horizontal strata. Lastly, this objection is obviated by a well-known fact. On all coasts where the ebbing and flowing of the sea is discernible, numbers of materials are brought in by the flux, which are not carried back by the reflux. The sea gradually increases on some places and recedes from others; narrowing its limits by depositing earth, sand, shells, &c. which naturally take a horizontal position. These materials when accumulated, and elevated to a certain degree, gradually float out the water, and remain for ever in the form of dry land.

15. The possibility of a mountain's being formed at the bottom of the sea by the motion and sediments of the water, will appear from the following considerations. On a coast which the sea washes with violence during the flow of tide, some part of the earth must be carried off at every stroke of the waves. Even where the sea is bounded by a rock, it is a known fact, that the rock itself is greatly wasted by the water; and consequently that small particles are carried off by the retreat of every wave. Those particles of earth or stone are necessarily transported to some distance. Whenever the agitation of the water ceases, the particles are precipitated in the form of a sediment, and lay the foundation of a first stratum, which is either horizontal or inclined, according to the situation of the surface on which they fall. This stratum is soon succeeded by another, produced by the same cause; and thus a considerable quantity of matter will be amassed, and deposited in parallel beds. In process of time this gradually accumulating mass will become a mountain in the bottom of the sea, exactly resembling, both in external and internal structure, those mountains which we see on the dry land. If there happened to be shells in that part of the bottom of the sea where we have supposed the sediments to be deposited, they will be covered, filled, and incorporated with the deposited matter, and form a part of the general mass. These shells will be lodged in different parts of the mountain, corresponding to the times in which they were deposited; those which lay at the bottom before the first stratum was formed, will occupy the lowest station; the others will be found in places more elevated.

16. It has been imagined that the agitation of the sea produced by the winds and tides is only superficial, and does not affect the bottom, especially where it lies very deep. But it ought to be remembered, that whatever be the depth, the whole mass is put in motion by the tides at the same time; and that, in a fluid globe, this motion would be communicated even to the centre. The attractive power, which occasions the flux and reflux, is penetrating. It acts equally upon every particle of the mass; so that the quantity of its force at different depths may be determined by calculation. We cannot therefore hesitate in pronouncing, that the tides, the winds, and all other causes of motion in the sea, must produce heights and inequalities in its bottom; and that these heights must uniformly be composed of regular strata either horizontal or inclined. The heights thus produced will gradually augment; like the waves which formed them, they will mutually respect each other; and if the extent of the base base be great, in a course of years they will form a vast chain of mountains.

17. Whenever eminences are formed, they interrupt the uniform motion of the waters, and produce currents. Between two neighbouring heights in the bottom of the ocean there must be a current which will follow their common direction, and, like a river, cut a channel, the angles of which will be alternately opposite through the whole extent of its course. These heights must continually increase; for, during the flow, the water will deposit its ordinary sediment upon their ridges; and the waters which are impelled by the current will force along, from great distances, quantities of matter, which will subside between the hills, and, at the same time, scoop out a valley with corresponding angles at their foundation. Now, by means of these different motions and sediments, the bottom of the ocean, though formerly smooth, must soon be furrowed and interspersed with hills and chains of mountains, as we actually find it at present. The soft materials of which the eminences were originally composed, would gradually harden by their own gravity. Such of them as consisted of sandy and crystalline particles would produce those enormous masses of rock and flint, in which we find crystals and other precious stones. Others, composed of stony particles mixed with shells, give rise to beds of limestone and marble in which vast quantities of sea-shells are still found incorporated.

18. These causes, as before observed, act with greater force under the equator than in other climates; for there the tides are higher, and the winds more uniform. The mountains of Africa and Peru are the highest in the world; often extending through whole continents, and stretching to great distances under the waters of the ocean. The mountains of Europe and Asia, which extend from Spain to China, are not so high as those of Africa and South America. According to the relations of voyagers, the mountains of the north are but small hills, when compared with the mountains of the equatorial regions. Those prodigious chains of mountains which run from east to west in the old continent, and from north to south in the new, must have been formed by the general motion of the tides. But the origin of the less considerable hills must be ascribed to particular motions occasioned by winds, currents, and other irregular agitations of the sea.

Having thus discussed some very important points respecting the theory of the earth, our author now proceeds to answer other questions which seem still more difficult of solution.

19. But how has it happened that this earth, which we and our ancestors have inhabited for ages, which, from time immemorial, has been an immense continent, dry, compact, and removed from the reach of water, should, if formerly the bottom of an ocean, be now exalted to such a height above the waters, and so completely separated from them? Since the waters remained so long upon the earth, why have they now deserted it? What accident, what cause, could introduce a change so great? A little reflection, says he, will furnish us with at least plausible solutions to these seemingly so difficult questions. We daily observe the sea gaining ground on certain coasts, and losing it on others. We know that the ocean has a general and uniform motion from east to west; that it makes violent efforts against the rocks and low grounds which encircle it; that there are whole provinces which human industry can hardly defend against the fury of the waves; and that there are instances of islands which have but lately emerged from the waters, and of regular inundations. History informs us of inundations and deluges of a more extensive nature. Ought not all this to convince us, that the surface of the earth has experienced very great revolutions, and that the sea may have actually given up possession of the greatest part of the ground which it formerly occupied? For example, let us suppose, that the old and new worlds were formerly but one continent; and that, by a violent earthquake, the ancient Atlantis of Plato was sunk. The consequence of this mighty revolution must necessarily be, that the sea would rush in from all quarters, and form what is now called the Atlantic Ocean; and vast continents, perhaps those we now inhabit, would of course be left dry. This great revolution might be effected by the sudden failure of some immense cavern in the interior parts of the globe, and an universal deluge would infallibly succeed.

20. But, however conjectures of this kind may stand, it is certain that such a revolution hath happened; and we may even believe that it hath happened naturally; for if a judgment of the future is to be formed from the past, we have only to attend carefully to what passes before our eyes. It is a fact established by the repeated observation of voyagers, that the ocean has a constant motion from east to west. This motion, like the trade-winds, is not only perceived between the tropics, but through the whole temperate climates, and as near the poles as navigators have approached. As a necessary consequence of this motion, the Pacific Ocean must make continual efforts against the coasts of Tartary, China, and India; the Indian Ocean must act against the east coast of Africa; and the Atlantic must in a similar manner act against all the eastern coasts of America. Hence the sea must have gained, and will always continue to gain, on the east, and to lose on the west. This of itself would be sufficient to prove the possibility of the change of the sea into land, and land into sea. If such is the natural effect of the sea's motion from east to west, may it not reasonably be supposed, that Asia, and all the eastern continent, is the most ancient country in the world? and that Europe, and part of Africa, especially the west parts of these continents, as Britain, France, Spain, &c. are countries of a more recent date?

21. The cause of the perpendicular fissures with which the earth abounds, is easily investigated. As various materials constituting the different strata were transported by the waters, and deposited in the form of sediments, they would at first be in a very dilute state, and would gradually harden and part with the superfluous quantity of moisture they contained. In process of time, drying, they would naturally contract and split at irregular distances. These fissures necessarily assumed a perpendicular direction; because in this direction the action of gravity of one particle upon another is equal to nothing; but it acts directly opposite to this description, in a horizontal situation: the di- minution in bulk could have no sensible effect but in a vertical line. The contraction of the parts in drying, therefore, and not the contained water forcing an issue, as has been alleged by some, is the cause of perpendicular fissures; for it may be often remarked, that the sides of those fissures, through their whole extent, correspond as exactly as the two sides of a split piece of wood.

22. Perpendicular fissures vary greatly as to the extent of their openings. Some are about half an inch or an inch; others a foot or two feet; some extend several fathoms, and give rise to those vast precipices which so frequently occur between opposite parts of the same rocks, in the Alps and other high mountains. It is plain, that the fissures, the openings of which are small, have been occasioned solely by drying. But those which extend several feet are partly owing to another cause; namely, the sinking of the foundation upon one side, while that of the other remains firm. If the base sinks but a line or two, when the height is considerable, an opening of several feet, or even fathoms, will be the consequence. When rocks are founded on clay or sand, they sometimes slip a little to one side; and the fissures are of course augmented by this motion.

23. The large openings, however, and prodigious cuts, which are to be met with in rocks and mountains, are to be ascribed to another cause. They could be produced no other way than by the sinking of immense subterranean caverns, that were unable any longer to sustain their incumbent load. But these cuts or intervals in mountains are not of the same nature with the perpendicular fissures: they appear to have been ports opened by the hand of nature for the communication of nations. This seems to be the intention of all large openings in chains of mountains, and of those straits by which different parts of the ocean are connected; as the straits of Thermopylae, of Gibraltar, &c., the gaps or ports in mount Caucasus, the Cordeliers, &c.

24. But the greatest changes upon the surface of the earth are occasioned by rains, rivers, and torrents from the mountains. These derive their origin from vapors raised by the sun from the surface of the ocean, and which are transported by the winds through every climate. The progress of these vapors, which are supported by the air, and transported at the pleasure of the winds, is interrupted by the tops of the mountains, where they accumulate into clouds, and fall down in the form of rain, dew, or snow. At first, these waters descend into the plains without any fixed course; but they gradually hollowed out proper channels for themselves. By the power of gravity they ran to the bottom of the mountains; and penetrating or dissolving the lower grounds, they carried along with them sand and gravel, cut deep furrows in the plains, and thus opened passages to the sea, which always receives as much water by rivers as it loses by evaporation. The windings in the channels of rivers have uniformly corresponding angles on their opposite banks; and as mountains and hills, which may be regarded as the banks of the valleys by which they are separated, have likewise sinuosities with corresponding angles, this circumstance seems to demonstrate, that the valleys have been gradually formed by currents of the ocean, in the same manner as the channels of rivers have been produced. Rivers produce considerable changes on the surface of the earth; they carry off the soil, wear away the most solid rocks, and remove every thing that opposes their passage. The waters of the clouds also, which descend upon the mountains, by continually washing away some part of the earth, tend to level them with the plains; and would undoubtedly do so, if time enough were allowed for that purpose.

25. From what has been advanced, we may conclude, that the flux and reflux of the ocean have produced all the mountains, valleys, and other inequalities on the surface of the earth: that currents of the sea have scooped out the valleys, elevated the hills, and bestowed on them the corresponding directions: that the same waters of the ocean, by transporting and depositing earth, &c., have given rise to the parallel strata: that the waters from the heavens gradually destroy the effects of the sea, by continually diminishing the height of the mountain, filling up the valleys, and choking up the mouths of rivers; and by reducing everything to its proper level, they will in time restore the earth to the sea, which by its natural operations will again create new continents interspersed with mountains and valleys, and every way similar to those which we now inhabit.

Thus far our author preserves some degree of plausibility in his reasoning; but in his account of the original formation of the earth, he certainly goes to the utmost verge of probability, or rather of possibility, in planets. According to him, all the planets in our system were originally parts of the sun himself. They were detached from his body all at once by a mighty stroke of a comet. The possibility of driving off such a quantity of matter from the sun by a single stroke, he labours hard to prove; but this is far from being the greatest difficulty in his system.—"To this theory (says he) it may be objected, that if the plants had been driven off from the sun by a comet, in place of describing circles round him, they must, according to the law of projectiles, have returned to the same place from whence they had been forced; and, therefore, that the projectile force of the planets cannot be attributed to the impulse of a comet.

"I reply, that the planets issued not from the sun in the form of globes, but in the form of torments; the motion of whose anterior particles behoved to be accelerated by those behind, and the attraction of the anterior particles would also accelerate the motion of the posterior; and that this acceleration, produced by one or both of these causes, might be such as would necessarily change the original motion arising from the impulse of the comet; and that, from the cause, might result a motion similar to what takes place in the planets; especially when it is considered, that the shock of the comets removes the sun out of its former station. This reasoning may be illustrated by an example. Suppose a musket ball discharged from the top of a mountain, and that the force of the powder was sufficient to send it beyond a semidiameter of the earth: it is certain that this ball would revolve round the earth, and return at every revolution to the place from whence it had been discharged. But, instead of a musket-ball, if a rocket were employed, the continued action of the fire would greatly accelerate the original original impulsive motion. This rocket would by no means return to the same point like the ball; but, *ceteris paribus*, would describe an orbit, the perigee of which would be more or less distant from the earth in proportion to the greatness of the change produced in its direction by the accelerating force of the fire. In the same manner, if the original projectile force impressed by the comet on the torrent of solar matter was accelerated, it is probable that the planets formed by this torrent acquired their circular or elliptical movements around the sun."

In like manner he accounts for the formation and circulation of the secondary planets. The revolutions of the primaries on their axes, he accounts for from the obliquity of the original stroke impressed by the comet. The oblate spheroidal figure of the earth is easily deduced from its diurnal motion, and the fluidity of the whole at its first formation. The flattening at the poles he estimates at about one 236th part of the whole. As this computation differs considerably from the account given by the mathematicians who were sent to different parts of the world on purpose to determine the figure of the earth, and who made the flatness at the poles equal to one 175th part of the whole, he supposes this difference to have arisen from changes that have since taken place on the surface of the earth, occasioned by the causes already mentioned. He then proceeds to account for the formation of all things, in the following manner.—"It is therefore evident, that the earth assumed its figure when in a melted state; and, to pursue our theory, it is natural to think, that the earth, when it issued from the sun, had no other form but that of a torrent of melted and inflamed matter; that this torrent, by the mutual attraction of its parts, took on a globular figure, which its diurnal motion changed into a spheroid: that when the earth cooled, the vapors, which were expanded like the tail of a comet, gradually condensed, and fell down in the form of water upon the surface, depositing at the same time a slimy substance mixed with sulphur and salts; part of which was carried by the motion of the waters into the perpendicular fissures of the strata, and produced metals; and the rest remained on the surface, and gave rise to the vegetable mould which abounds in different places, with more or less of animal or vegetable particles, the organization of which is not obvious to the senses.

Thus the interior parts of the globe were originally composed of vitrified matter; and, I believe, they are so at present. Above this vitrified matter were placed those bodies which the fire had reduced to the smallest particles, as sands, which are only portions of glass; and above these pumice-stones and the scoriae of melted matter, which produced the different clays. The whole was covered with water to the depth of 500 or 600 feet, which originated from the condensation of the vapors when the earth began to cool. This water deposited a stratum of mud, mixed with all those matters which are capable of being sublimed or exhaled by fire; and the air was formed of the most volatile vapors, which, from their levity, rose above the water.

Such was the condition of the earth when the tides, the winds, and the heat of the sun, began to introduce changes on its surface. The diurnal motion of the earth, and that of the tides, elevated the waters in the equatorial regions, and necessarily transported thither great quantities of lime, clay, and sand; and by thus elevating those parts of the earth, they perhaps sunk those under the poles about two leagues, or a 236th part of the whole, as was formerly remarked: for the waters would easily reduce into powder-pumice-stones, and other spongy parts of the vitrified matter upon the surface; and by this means excavate some places and elevate others, which, in time, would produce islands and continents, and all those inequalities on the surface, which are more considerable towards the equator than towards the poles. The highest mountains lie between the tropics and the middle of the temperate zones, and the lowest from the polar circles towards the poles. Indeed, both the land and sea have most inequalities between the tropics, as is evident from the incredible number of islands peculiar to those regions."

V. In the first volume of the Edinburgh Philosophical Transactions a new theory of the earth has been laid down at considerable length by Dr Hutton; of which the following is an abstract.

The general view of the terrestrial system conveys to our minds an idea of a "fabric, erected in wisdom, to obtain a purpose worthy of the power that is apparent in the production of it."

The end for which it was formed, as far as we can comprehend our author's meaning, is, that it might be an habitation for living creatures; and we are enabled to understand the constitution of this earth as a thing formed by design, "not only by seeing those general operations which depend on its construction as a machine, but also by perceiving how far the particulars in the construction of that machine depend on the operations of the globe."

In taking a comprehensive view of the mechanism of the globe, we observe three principal parts of which it is composed; and which, by being properly adapted to one another, form it into an habitable world. These parts are the solid body of the earth, the waters of the ocean, and the atmosphere surrounding the whole. On these our author observes,

1. The parts of the terrestrial globe move immediately exposed to our view are supported by a central body commonly supposed, but without any good reason, to be solid and inert.

2. The aqueous part, reduced to a spherical form by gravitation, has become oblate by the earth's centrifugal force. Its use is to receive the rivers, be a fountain of vapors, and to afford life to innumerable animals, as well as to be the source of growth and circulation to the organized bodies on earth.

3. The irregular body of land, raised above the level of the sea (though the smallest of these large divisions), is by far the most interesting, as immediately necessary to the support of animal life.

4. The atmosphere surrounding the whole is evidently necessary for innumerable purposes of life and vegetation, neither of which could subsist a moment without it.

Having thus considered the mechanism of the globe, Dr Hutton proceeds to investigate the powers by which it is upheld.—These are the gravitating and upheld, projectile forces by which the planets are guided, the influence... influence of light and heat, cold and condensation; to which may be added electricity and magnetism.

In the further pursuit of our general or preparatory ideas, the Doctor observes, that "a solid body of land could not have answered the purpose of a habitable world, for a soil is necessary for the growth of plants; but a soil is only the materials collected from the destruction of the solid land. Therefore the surface of this land, inhabited by man, is made by nature to decay, in dissolving from the hard and compact state in which it is found below the soil; and this soil is necessarily washed away by the continual circulation of the water running from the summits of the mountains." Thus he supposes that the land must at last be entirely destroyed; a misfortune unavoidable from the very constitution of the globe as an habitable world. It remains, therefore, to be considered, whether there be, "in the constitution of this world, a reproductive operation by which a ruined constitution may be again repaired, and a duration and stability procured to the machine considered as capable of sustaining plants and animals?" The solution of this question, he says, is perhaps within the reach of human sagacity, and, as he justly observes, might add some lustre to science and the human intellect.

With regard to the beginning of the world, though our author does not pretend to lay aside the Mosaic accounts concerning the origin of man, yet says he, "though there has not been found in natural history any document by which a high antiquity might be attributed to the human race, this is not the case with regard to the inferior animals, particularly those which inhabit the ocean and its shores. We find in natural history monuments which prove that these animals had long existed; and we thus procure a measure for the computation of a period of time extremely remote, though far from being exactly ascertained.—Thus, in finding the relics of sea animals of every kind in the solid body of the earth, a natural history of those animals is formed, which includes a certain portion of time; and for the ascertaining this portion of time, we must again have recourse to the operations of this world.

From a view of the present construction and operations of nature, therefore, our author supposes, that we may understand what has formerly passed in the original formation of the globe; and then proceeds to reason in the following manner:

The solid parts of the globe are, in general, composed of sand, gravel, argillaceous and calcareous strata, or of these mixed with some other substances. Sand is separated and fixed by streams and currents; gravel is formed by the mutual attrition of stones agitated in water; and marly or argillaceous strata have been collected by subiding in water in which those earthy substances had floated. Thus, so far as the earth is formed of these materials, it would appear to have been the production of water, winds, and tides.

The next inquiry of our author is into the origin of our land, which he seems willing to derive entirely from the exuviae of marine animals. The only argument he makes use of for determining this most important point is drawn from the quantity of them to be met with in the different parts of it. "We find (says he) the marks of marine animals in the most solid parts of the earth; consequently those solid parts have been formed after the ocean was inhabited by those animals which are proper to that fluid medium."

That all the masses of marble or limestone are composed of the calcareous matter of marine bodies, he concludes, 1. From there being few in which some or totally to those objects may not be found which indicate the marine origin of the mass; and a single cockle-shell or piece of coral found in a marble or limestone quarry, will certainly prove it to have been originally at the bottom of the sea as much as if it had been all composed of such bodies. 2. In the calcareous strata, which are evidently of marine origin, there are many parts of a sparry structure; which shows that in these places the original texture of those beds has been dissolved and a new structure assumed. This change is produced by crystallization, in consequence of a previous state of fluidity; which has so disposed the concreting parts, as to allow them to assume a regular shape and structure proper to that substance. 3. There are, in all the regions of the earth, huge masses of calcareous matter in that crystalline or sparry state, in which perhaps no vestige can be found of any organized body, nor any indication that such calcareous matter had belonged to animals; but as, in other masses, this sparry or crystalline state is evidently assumed by the calcareous matter of the marine productions, we have no reason to derive these from any other source; and hence, says our author, we are led to conclude, that all the strata of the earth, not only those consisting of such calcareous masses, but others superincumbent upon these, have had their origin at the bottom of the sea, by the collection of sand and gravel, of shells, of coralline and crustaceous bodies, and of earths and clays variously mixed, or separated and accumulated.

"The general amount of our reasoning (says he) is this: Almost the nine-tenths perhaps, or 99 hundredths, of this earth, whole body so far as we see, have been formed by natural operations of earth of the globe, in collecting loose materials and depositing them at the bottom of the sea, consolidating the bottom of those collections in various degrees, and either elevating those consolidated masses above the level on which they were formed, or lowering the level of that sea."

With regard to the raising of the land, thus formed at the bottom of the sea, to some height above its raised surface, our author differs from Buffon, and contends, from thence that "no motion of the sea occasioned by the earth revolving in this solar system could bring about that end; for let us suppose the axis of the earth to be changed from the present poles and placed in the equinoctial line, the consequence of this might indeed be the formation of a continent of land about each new pole, from whence the sea would run towards the new equator; but all the rest of the globe would remain an ocean. Some new points might be discovered, and others which appeared before above the surface of the sea would be sunk by the rising of the water; but, on the whole, land could only be gained substantially at the poles. Nor could the continents, even supposing they had been originally produced in this manner, have continued stationary for many thousand years, and presented to us, everywhere below their surface, masses of consolidated marble and other mineral substances, in a state as different as possible from what they were originally. Besides an operation, therefore, by which the earth at the bottom of the sea should be converted into an elevated land, or placed high above the level of the ocean, there is required a consolidating power, by which the loose materials that had subsided from water should be formed into masses of the most perfect solidity, having neither water nor vacuity between their constituent parts, nor in the pores of these constituent parts themselves.

This consolidating power, he is of opinion, must lie out of the reach of common observation, because the consolidated masses on the surface of the earth are now in a state of decay; and therefore we must look into these masses themselves, in order to discover the cause by which they assumed their present form.

In entering upon the investigation of this consolidating power, our author observes, that there are only two ways in which the requisite changes can happen, viz. simple congelation from a fluid state, or a continual accretion of solid particles. Fire and water, therefore, may be considered as the general agents in this operation; and we are to consider whether they have acted in the way of aqueous solution and crystallization, or in that of fusion. If the former of these ways is supposed to be that in which the strata in general have been consolidated, we may look for a considerable degree of uniformity in its effects. "The action of water (he says) upon all different substances is what we are well acquainted with; and there is no reason to conclude anything mysterious in its operation, unless we suppose an immense compounding power to have some effect in altering it. Compression, however (he says), only alters the relation of evaporation to heat, or changes the degree of heat which water can contain. We are therefore to look for no occult quality in water acting at the bottom of the sea more than on the surface of the earth. Time, indeed, may do a great deal where the course of the operation is slow; but where it is contrary to the nature of the things to produce the change in question, it is plain that no length of time can have any effect."

Again, if the masses have been consolidated by crystallization, the bodies must first have been dissolved in water as a menstruum; and therefore another power is to be sought for by which the water might again be extricated from those endless labyrinths in which the solid matter of the strata is deposited, without leaving a fluid particle in its composition. There is likewise another difficulty in finding a source from whence the vast quantity of matter deposited in these strata should be derived. Besides, the water contained in the cavities and interstices of these bodies composing strata must be in a stagnating state; and consequently it can only act on the surface of these cavities which are to be filled up. "But with what are they to be filled? Not with water; they are full of this already: Not with the substance of those bodies which contain the water; this would be only to make one cavity in order to fill up another. If, therefore, the cavities of the strata are to be filled with solid matter by means of water, there must be made to pass through these porous masses water impregnated with some other substances in a dissolved state, and the aqueous menstruum must be separated from the dissolved substance, and to deposit the same in cavities through which the solution moves." This supposition is, however, according to our author, inadmissible; for, in the case of materials accumulated in the bottom of the ocean, there is no proper means for separating the dissolved matter from the water included in these enormous masses; nor are there any means by which a circulation in these masses may be formed.

In the further prosecution of his subject, our author informs us, that "if water had been the menstruum by which the consolidating matter was introduced into the cavities of the strata, masses of those bodies that are soluble in water could only be found consolidated; and these only in such a state as the simple separation of the dissolving water might produce. But this is far from being the case. We have strata consolidated by calcareous spar; a thing perfectly distinguishable from the flaky concretion of the calcareous earth in consequence of aqueous solution. We have strata made insoluble in solid by the formation of fluor; a substance, so far as we know, not soluble in water. We have strata consolidated with sulphureous and bituminous substances, which do not correspond to the solution in water. We have strata consolidated with siliceous matter in a state totally different from that in which it is deposited by water; we have them also consolidated by almost all the various metallic substances, with their almost endless mixtures and sulphureous compositions; that is to say, we find perhaps every different substance introduced into the interstices of strata which had been formed by submersion at the bottom of the sea."

For these reasons, our author thinks it more probable that the strata have been consolidated by heat and fusion; and this hypothesis, he imagines, will solve every difficulty. And as the question is of the greatest importance to natural history, he proposes to investigate it at great length; at the same time that the subject is generalized as much as possible.

He considers, that among the various strata which compose the earth, we find some strata formed of siliceous and some of sulphureous materials; and with one or other, or both of these substances, the strata are so intimately mixed, that what has changed the siliceous or sulphureous materials from a fluid to a solid state, must likewise have materially affected the strata which contain them. The former he looks upon to be absolutely insoluble in water; and there are many other bodies supposed absolutely insoluble in water; whose solubility is so small, that it could not be discovered but by means of the siliceous matter. Of this instance is adduced in the feldspar, a compound of siliceous, argillaceous, and calcareous earth, intimately united together; which being for ages exposed to the weather, the calcareous part is dissolved, and the siliceous left in form of a white soft earth; though it is uncertain whether this dissolution be performed by means of pure water, or whether an acid be also concerned. Siliceous matter is undoubtedly contained in the water of the boiling fountain of Geyser in Ireland; but he thinks that here it must be dissolved by an alkali, one of the natural solvents of this fountain of Geyser. "It may therefore be asserted (says he), that no siliceous body having the hardness of flint, nor any crystallization of that substance, has ever been formed except by fusion. If by any art this substance shall be dissolved in simple water, or made to crystallize from any solution, in that case the assertion which has been here made may be denied." But besides this proof he adduces another, supposed to be more direct; and that is, the penetration of many bodies with a flinty substance, which, according to every collateral circumstance, must have been performed by the flinty matter in a state of simple fusion, and not in a state of suspension by any solvent. Flinty bodies are found perfectly insulated in strata of chalk and sand; and here our author determines that it is not possible that flint matter could be conveyed into the middle of these strata by a menstruum in which it was dissolved, and thus deposited in that place, without the smallest trace of deposition in the neighbouring parts. The form of these bodies also demonstrates, in his opinion, "1. That they have been introduced among those strata in a fluid state, by injection from some other place; 2. That they have been dispersed in a variety of ways among those strata then deeply immersed at the bottom of the sea; and, 3. That they have been there congealed from the state of fusion, and have remained in that situation, while those strata have been removed from the bottom of the ocean to the surface of the present land."

There are also specimens brought from many different places, which contain in themselves the most evident marks of this injection of the flinty substance in a fluid state; and these are pieces of fossil wood brought from England, Germany, and Loch Neagh in Ireland. Sometimes those specimens appear to have been previously penetrated by an iron or calcareous matter, and sometimes not: "The injected flint, however (says he), appears to have penetrated the body of this wood immersed at the bottom of the sea, under an immense compression of water. This appears from the wood being penetrated partially, some parts not being penetrated at all. Now, in the limits betwixt these two parts, we have the most convincing proofs that it had been flint in a simple fluid state which had penetrated the wood, and not in a state of solution.

"Firstly, Because, however little of the wood is left unpenetrated, the division is always distinct between the injected part and that which is not penetrated by the fluid flint. In this case the flinty matter has proceeded a certain length, which is marked, and no farther; and beyond this boundary there is no partial impregnation, nor a gradation of the flintifying operation, as there must have been if siliceous matter had been deposited from a solution 2dly. The termination of the flinty impregnation has assumed such a form precisely as would have happened naturally from a fluid flint penetrating that body.

"In other specimens of this mineralizing operation, fossil wood, penetrated more or less with ferruginous or calcareous substance, has been afterwards penetrated with a flinty substance. In this case, with whatever different substances the woody body shall be supposed to have been penetrated in a state of solution by water, the regular structure of the plant would still have remained, with its vacuities variously filled with the petrifying substances, separated from the aqueous menstruum, and deposited in the vascular structure of the wood.

"There cannot be a doubt with regard to the truth of this proposition; for, as it is, we frequently find parts of the consolidated wood with the vascular structure remaining perfectly in its natural shape and situation; but if it had been by aqueous solution that the wood had been penetrated and consolidated, all the parts of that body would be found in the same natural shape and situation.

"This, however, is far from being the case; for while in some parts the vascular structure is preserved entire, it is also evident, that in general the woody structure is variously broken and dissolved by the fusion and crystallization of the flint."

With regard to the second kind of substances to be Of the substances considered, and which are called by our author sulphurous, he tells us, "that they are not soluble in water so far as we know, but fusible by heat, and inflammable by means of heat and vital air. They are either more simple or more compound. The former consist of phlogiston united either with acid or metallic substances, the one forming sulphur, properly so called, the other metals. The more compound kind are composed of oily matter produced by vegetables, and forming bituminous substances.

"Sulphur is found naturally combined with metals, which are said to be mineralized by it; and it is well known that this mineralization is performed by means of heat and fusion; nor will any person skilled in chemistry pretend to say that this is done in the way of aqueous solution. The combination of iron and sulphur, for instance, may be easily performed by fusion; but this compound is resolved into a vitriolic salt by aqueous solution."

Our author further remarks, that unless all the substances of this kind were soluble in water, we ought not to say that any one of them is formed by aqueous solution; for there is such a continued chain of connection between them, that all must have been formed either by aqueous solution or by means of heat and fusion. In one mass, for instance, we find, 1. Pyrites containing sulphur, iron, and copper; 2. Blend, consisting of iron, sulphur, and calamine; 3. Galena containing lead and sulphur; 4. Marmor metallicum, consisting of terra ponderosa saturated with the vitriolic acid, a substance insoluble in water; 5. A saturation of calcareous earth with the acid of fluor, forming a substance likewise insoluble in water; 6. Calcareous spar of different kinds, being calcareous earth saturated with fixed air, and something also which makes a variety; And, lastly, Siliceous substance, or quartz crystals. Unless, therefore, every one of these different substances were soluble in water, and crystalizable from it, we will look in vain for any explanation of these appearances by means of aqueous solution; while heat being capable of rendering all these substances fluid, they may be with the greatest simplicity transported from one place to another; and they may be made to concrete altogether at the same time, and distinctly separate in any place.

But what puts the matter beyond all doubt with our supposed author, is a specimen of ore taken from an Hungarian mine, and which contains petro-filex, pyrites, and cinabar, so mixed together and crystallized upon one another, that it is impossible to conceive any one of these bodies to have had its fluidity and concretion from a cause which had not affected the other two.

"Now (says our author), let those who would deny the fusion of this siliceous body explain how water could dissolve these three different bodies, and deposit them in their present shape. If, on the contrary, they have have not the least shadow of reason for such a gratuitous supposition, the present argument must be admitted in its full force."

The next argument in favour of our author's doctrine is drawn from the existence of metallic bodies in their malleable state in the bowels of the earth. In this situation they are also commonly attended with such evident marks of fusion, that it is impossible to deny their having been really melted; and for the truth of this he appeals, among a thousand instances, to the great native mass of iron found by Dr Pallas in Siberia.

Oily or bituminous bodies are found variously intermixed with mineral substances, as well as forming distinct strata of themselves. Vegetables afford oily and resinous matters; which being collected at the bottom of the ocean are there formed into strata, afterwards changed by various degrees of heat, and the evaporation of their more fluid parts. "In order to understand this (says our author), it must be considered, that while immersed in water, and under insuperable compression, the vegetable, oily, and resinous substances would appear to be unalterable by heat; and it is only in proportion as certain chemical separations take place, that those inflammable bodies are changed in their substance by the application of heat. Now, the most general change of this kind is by evaporation, or the distillation of their more volatile parts; by which oily substances become bituminous, and bituminous substances become coaly. There is here a gradation, which is best understood by comparing the two extremes. On the one hand, we know by experiment, that oily and bituminous substances can be melted, and partly changed into vapour by heat; and that they become harder and denser in proportion as the more volatile parts have evaporated from them. On the other hand, coaly substances are destitute of fusibility and volatility, in proportion as they have been exposed to greater degrees of heat, and to other circumstances favourable to the distillation of their more volatile and fluid parts. If, therefore, in mineral bodies we find the two extreme states of this combustible substance, and also the intermediate states, we must either conclude that this particular operation of heat has been thus actually employed in nature, or we must explain those appearances by some other means in as satisfactory a manner, and so shall be consistent with other appearances. In this case it will avail nothing to have recourse to the false analogy of water dissolving and crystallizing salts, which has been so much employed for the explanation of other mineral appearances. The operation here in question is of a different nature, and necessarily requires both the powers of heat and proper conditions for evaporation. Therefore, in order to decide the point with regard to what is the power in nature, by which mineral bodies have become solid, we have only to find a bituminous substance in the most complete state of coal, intimately connected with some other substance which is more generally found consolidating the strata, and assailing in the concretion of mineral substances. A most undoubted proof of this kind our author has in his possession, viz. a mass in which are blended together coal of the most fixed kind, quartz, and marmor metallicum. The specimen also is contained in a rock, which every naturalist, he says, will allow to have been produced by fire and fusion.

The strata of fossil coal are found in almost every intermediate state, as well as in those of bitumen and the different kinds of charcoal. Of the former kind is that fossil coal which melts and becomes fluid by heat; of the latter, is that species found both in Wales and Scotland, which is perfectly infusible in the fire, and burns like coals without flame or smoke. The former abounds in oily matter; the latter has been distilled by heat until it has become a caput mortuum, or perfect coal. The more volatile parts of these bodies are sometimes found in their separate state. Thus at Raith in Fifehire, there is a stratum of limestone, which, though but slightly tinged containing with a black colour, contains bituminous matter like liquid bituminous pitch, in many cavities which are lined with calcareous spar crystallized. Now, it is to be observed, that had the cavity in the solid limestone or marble, which is lined with calcareous crystals containing pyrites, been thus incrustated by means of filtration with water, this water must have dissolved calcareous spar, pyrites, and bitumen. But these natural appearances would not even be solved by this hypothesis of dissolution and filtration of these substances. There is also required, first, a cause for the separation of these different substances from the aqueous menstruum. 2. An explanation of the way in which a bitumen should be formed into hard round bodies (our author has a specimen of this kind) of the most solid structure; and, lastly, some probable means for this complicated operation being performed below the bottom of the ocean, in the close cavity of a marble stratum.

Having thus run through his course of argument for the probability of the strata of earth being formed by heat and fusion rather than by aqueous solution, our author proceeds to the examination of a phenomenon in the mineral kingdom, which may be thought inconsistent with what he has advanced; viz. the existence of great masses of salt in the bowels of the earth. On the present subject he observes, that the formation of masses of salt at the bottom of the sea, without the assistance of subterranean fire, is not a thing unfavourable as at first sight might appear. "Let us but suppose a rock placed across the gut of Gibraltar (a case not unnatural), and the bottom of the Mediterranean would be certainly filled with salt; because the evaporation from the surface of that sea exceeds the measure of its supply. But strata of salt formed in this manner at the bottom of the sea are as far from being consolidated by means of aqueous solution as a bed of sand in the same situation; and we cannot suppose the consolidation of such a stratum of salt by means of water, without supposing subterranean heat employed to evaporate the brine which would successively occupy the interstices of the saline crystals. But this, it may be observed, is equally departing from the natural operation of water as the means for consolidating the sediment of the ocean, as if we were to suppose the same thing done by heat and fusion. For the question is not, if subterranean heat be of sufficient intensity for the purpose of consolidating strata by the fusion of their substances? but, whether it be by means of this agent, subterraneous heat, or by water alone, without the operation of melting, melting heat, that those materials have been variously consolidated."

The Doctor now attempts to prove, from the appearance of the saline strata, that they have been formed by subterranean heat and fusion as well as the others.

"The salt-rock in Cheshire lies in strata of red marl. It is horizontal in its direction, and is dug 30 or 40 feet deep. The body of this rock is perfectly solid, and the salt in many places pure, colourless, and transparent, breaking with a sparry, cubical texture; but the greatest part is tinged by the admixture of the marl, and that in various degrees, from the slightest tinge of red to the most perfect opacity. Thus the rock appears as if it had been a mass of fluid salt, in which had been floating a quantity of marly substance not uniformly mixed, but everywhere separating and subsiding into the saline substance. There is also to be observed a certain regularity in the separation of the tingeing from the colourless substance; which, at a proper distance, gives to the perpendicular section of the rock a distinguishing figure in its structure. When looking at this appearance near the bottom of the rock, it first presented the figure of regular stratification; but upon examining the whole mass of rock, this stratification was found only to take place near the bottom. At the top of the rock, the most beautiful figure, though the most distant from stratification, was observed. It was all composed of concentric circles, and these appeared to be the section of a mass made up entirely of concentric spheres, like those beautiful figures of configuration which agates so frequently present us with in miniature. In about eight or ten feet from the top, the circles growing large, were blended together, and gradually lost their regular appearance, until at a greater depth they again assumed that of a regular stratification. This regular arrangement of the floating marly substance in the body of the salt, which is that of the structure of a coated pebble, or that of concentric spheres, is altogether inexplicable upon any other supposition than the perfect fluidity or fusion of the salt, and the attractions and repulsions of the contained substances. It is in vain to look in the operations of solution and evaporation for that which nothing but perfect fluidity and fusion can explain.

"This example of a mineral salt congealed from a melted state, may be confirmed by another argument suggested by Dr Black, viz., an alkaline salt found in a mineral state, and described in the Philosoph. Transact. for 1771. The fossil alkali crystallizes from a dissolved state, in combining itself with a large quantity of water, in the manner of alum: and in this case the water is essential to the constitution of that solid crystalline body; for, upon the evaporation of the water, the transparent salt loses its solidity, and becomes a white powder. If, instead of being gently dried, the crystalline salt is suddenly exposed to a sufficient degree of heat (that is, somewhat more than the heat of boiling water), it enters into the state of aqueous fusion, and boils, emitting the water by means of which it had been crystallized in the cold, and rendered fluid in that heated state. It cannot be crystallized from a dissolved state without the combination of that quantity of water; nor can that water be separated without destroying its crystalline state. But in this mineral specimen we have a solid crystalline salt, with a structure which, upon examination, appears to be sparry and radiated like the zeolite. It contains no water in its crystallization, but melts in a sufficient heat without any aqueous fusion. Therefore this salt must have been in a fluid state of fusion immediately before its congelation and crystallization.

"Another example may be drawn from the ironstone, which is commonly found among the argillaceous strata attendant upon fossil coal, both in Scotland and England. This stone is generally found among the bituminous schistus or black argillaceous strata, either in separate masses of various shapes and sizes, or forming of itself strata which are more or less continuous in their direction among the schistus or argillaceous beds. This mineral contains in general from 40 to 50 per cent. of iron, and it loses near one-third of its weight in calcination. Before calcination it is of a grey colour, is not penetrable by water, and takes a polish. In this state therefore it is perfectly solid; but being calcined, it becomes porous, red, and tender. The fact to be proved with regard to these ironstones is, that they have acquired their solid state from fusion, and not in concreting from any aqueous solution. A species of this kind of stone is found at Aberlady in East Lothian, resembling an oblate or much compressed sphere, and the size from two or three inches diameter to more than a foot. In the circular or horizontal section they present the most elegant septarium: and from the examination of this particular structure, the following conclusions may be drawn.

"1. That the septa have been formed by the uniform contraction of the internal parts of the stone, to have received its volume of the central parts diminishing more than that of the circumference; by which means the separations of the stone diminish in a progression from the centre towards the circumference.

"2. There are only two ways in which the septa must have received the spar with which they are filled more or less; either, firstly, by infiltration into the cavity of the septa after they were formed; or, secondly, by separation from the substance of the stone at the same time that the septa were forming.

"Were the former of these suppositions true, appearances would be observable, showing that the spar of this stone substance had been admitted either through the porous structure of the stone, or through proper apertures filled by a communicating from without. Now, if either of these aqueous fluids had been the case, and the stone had been conglobulated from no other cause than concretion from a dissolved state, that particular structure of the stone by means of which the spar had been admitted must appear at present upon an accurate examination. This, however, is not the case; and we might rest the argument here: The septa reach not the circumference; the surface of the stone is solid and uniform in every part; and there is not any appearance of the spar in the argillaceous earth around the stone. It therefore necessarily follows, that the contraction of the iron-stone, in order to form the septa, and the filling the cavities with spar, had proceeded pari passu; and that this operation must have been brought about by means of fusion or by congelation from a state of simple fluidity and expansion.

"There is one fact more, which is well worth our attention; viz., the crystallizations which are found in close..." closet cavities of the most solid bodies. These concretions are well known to naturalists, and form part of the beautiful specimens which are to be found in the cabinets of collectors, and which the German mineralists have named drusen." Our author, however, considers only one of these species, which is of the agate kind. It belongs to the kind of stones frequent in this country, which are commonly called pebbles. Many of them are filled with a siliceous crystallization, which evidently proceeds from the circumference towards the centre. Many of them again are hollow. They are uniformly lined with crystallized substances; and it is proper to attend to this circumstance, that the cavity is perfectly inclosed with many solid coats impervious to air or water; but particularly with the external cortical part, which is extremely hard, takes the highest polish, and is of the most perfect solidity, admitting nothing but the passage of light and heat.

"Within these cavities we find, first, the coats of crystals with which this cavity is always lined; and this is general to all substances concreting in similar circumstances from a state of fusion; for when thus at liberty they naturally crystallize. 2. We have frequently a subsequent crystallization set upon the first, and more or less immersed in it. 3. There is also sometimes a third crystallization superincumbent on the second, in like manner as the second was upon the first. Our author has one specimen in which the primary crystals are siliceous; the second thin foliaceous crystals of deep red but transparent ore, forming elegant figures that have the form of roses; the tertiary crystallization is a coating of small siliceous crystals upon the edges of the foliaceous crystals. In other specimens there is first a lining of colourless siliceous crystals, then another lining of amethystine crystals, and sometimes within that fuliginous crystals. Upon these fuliginous and amethystine crystals are many spherules or hemispheres of red compact iron-ore like hematites. In others again, the primary crystals are foliaceous, and the secondary calcareous. Of this kind there is one in the Doctor's possession, which has upon the calcareous crystals beautiful transparent siliceous crystals, and iron spherules upon these. He has also an agate formed of various red and white coats, and beautifully figured. The cavity within the coated part of the pebble is filled up without vacancy; first with colourless siliceous crystals; secondly, with fuliginous crystals; and, thirdly, with white or colourless calcareous spar. But between the spar and crystals there are many spherules, seeming of iron, half sunk into each of these two different substances."

From the foregoing facts our author now draws the following conclusions.

1. That concretion had proceeded from the surface of the agate inwards. This necessarily follows from the nature of those figured bodies, the figures of the external coats always determining the shape of those within, and never contrariwise, those within affecting those without.

2. That when the agate was formed, the cavity then contained every thing which is now found in it, and nothing more.

3. That the contained substances must have been in a fluid state, in order to their crystallizing.

4. That as this fluid state had not been the effect of solution in a menstruum, it must have been fluidity from heat and fusion."

This is the substance of all the evidence brought by Dr Hutton in support of his doctrine, that most of the mineral substances with which the strata are conjoined must have been produced by subterraneous heat, and not from any aqueous solution. Thus far he thinks it is perfectly conclusive, though not altogether so strong as to make it apply also to these, he next proposes to give examples of strata consolidated with the introduction of foreign matter, merely by the softening or fusion of their own materials.

For this purpose he considers the calcareous and siliceous strata, which are the two most prevalent on the surface of the globe, that all others, according to him, may be considered as nothing: "for (says he) unless it be the bituminous or coal strata, there is hardly any other which does not contain more or less of one or other of these two substances. If therefore it can be shown, that both of these two general strata have been consolidated by the simple fusion of their substance, no delusion or doubt will remain with regard to the nature of that operation which has been transected at great depths of the earth, places to which all access is denied to mortal eyes.

"We are now to prove, 1. That those strata have been consolidated by simple fusion; and, 2. That this operation is universal in relation to the strata of the earth, as having produced the various degrees of hardness or solidity in these bodies.

"I shall first remark, that a fortuitous collection of consolidated hard bodies, such as gravel and sand, can only touch in points, and cannot while in that hard state be made to correspond precisely to each other's shape as to consolidate the mass. But if these hard bodies should be softened in their substance, or brought into a certain degree of fusion, they might be adapted mutually to each other; and thus consolidate the open structure of the mass. Therefore, to prove the present point, we have but to exhibit specimens of siliceous and calcareous strata which have been evidently consolidated in this manner. Of the first kind great varieties occur in this country. They are the consolidated strata of gravel and sand, often containing abundance of feldspar, and thus graduating into granite; a body, in this respect, perfectly similar to the more regular strata which we now examine. The second kind again are less common, unless we consider the shells and coralline bodies of our limestones as exhibiting the same example, which indeed they do. But I have a specimen of marble from Spain which will afford the most satisfactory evidence of the fact in question. This Spanish marble may be considered as a species of pudding-stone; a species of marble which, from Mr Bowles's Natural History, appears to be very common in Spain. The gravel of which this marble is composed consists of fragments of other marbles of different kinds. Among these are different species of zeolites, marble, some shell marbles, and some composed of a chalky substance, or of undistinguishable parts. But it appears that all these different marbles had been consolidated or made hard, then broken into fragments, rolled and worn by attrition; and thus collected together, along with some sand or small siliceous bodies, into into one mass. Lastly, this compound body is consolidated in such a manner as to give the most distinct evidence that this had been executed by the heat of simple fusion.

"The proof is, that, besides the general conformation of those hard bodies, so as to be perfectly adapted to each other's shape, there is in some places a mutual indentation, which resembles perfectly the junction of the different bones of the cranium; and which must necessarily have required a mixture of those bodies while in a soft or fluid state.

"This appearance of indentation is by no means singular or limited to one particular specimen. I have several specimens of different marbles, in which fine examples of this species of mixture may be perceived. But in this particular case of the Spanish pudding-stone, where the mutual indentation is made between two pieces of hard stone worn round by attrition, the softening or fusion of these two bodies is not simply rendered probable, but demonstrated.

"Having thus proved, that those strata had been consolidated by simple fusion, as proposed, we now proceed to show, that this mineral operation had been not only general but universal, in consolidating our earth in all the various degrees, from loose and incoherent shells and sand to the most solid bodies of the siliceous and calcareous substances.

"To exemplify this in the various collections and mixtures of sands, gravels, shells, and corals, were endless and superfluous. We shall only take for an example one simple homogeneous body, in order to exhibit it in the various degrees of consolidation, from the state of simple incoherent earth to that of the most solid marble. The substance meant is chalk, naturally a soft calcareous earth, but which may be found consolidated in every different degree.

"Through the middle of the isle of Wight there runs a ridge of hills of indurated chalk. This ridge runs from the isle of Wight directly west into Dorsetshire, and goes by Corfe Castle towards Dorchester, perhaps beyond that place. The sea has broke through this ridge at the west end of the isle of Wight, where columns of the indurated chalk remain, called the Needles; the same being found on the opposite shore in Dorsetshire. In this field of chalk we find every gradation of this soft earthy substance to the most consolidated body of this indurated ridge, which is not solid marble, but which has lost its chalky property, and acquired a kind of stony hardness.

"We have this cretaceous substance in its most indurated and consolidated state in the kingdom of Ireland, not far from the Giant's Causeway; and it affords the most perfect evidence of this body having been once a mass of chalk, which is now a body of solid marble. Thus, if it is by means of fusion that the strata of the earth have in many places been consolidated, we must conclude that all the degrees of consolidation, which are indefinite, have been brought about by the same means.

"It may, however, still be alleged, that there is a great part of the solid mass of this earth not properly comprehended among those bodies which have been thus proved to be consolidated by means of fusion. This is granite; a mass which is not generally stratified, and which being a body perfectly solid, and forming some parts in the structure of this earth, deserves to be considered. The nature of the granite is too intricate a subject to be here considered; we shall therefore only now take notice of one species; and if this appears to have been once in a state of fusion, we must conclude that all the rest have been so too.

The species in question comes from Portfoy, on the road to Huntley; and is partly a porphyry and partly of a species of granite. The singularity of it, however, consists not in the nature or proportions of its constituent parts, but in the uniformity of the sparly ground, and the regular shape of the quartz mixture. This filaceous substance, viewed in one direction, or longitudinally, may be considered as columnar, prismatical, or continued in lines running nearly parallel. These columnar bodies of quartz are beautifully impressed with a figure on the sides, where they are in contact with the spar. This figure is that of furrows or channels, which are perfectly parallel, and run across the longitudinal direction of the quartz. This striated figure is only seen when, by fracture, the quartz is separated from the contiguous spar. But what is more particularly to be noticed is, that the transverse section of those longitudinal bodies not only have separately the forms of certain typographical characters, but collectively give the regular linear appearance of types set in writing.

"It is evident from the inspection of this fossil, that the sparly and filaceous substances had been mixed together in a fluid state; and that the crystallization of the sparly substance, which had been rhombic, had determined the regular structure of the quartz, at least in some directions. Thus the filaceous substance is to be considered as included in the spar, and as figured according to the laws of crystallization proper to the sparly ground; but the spar is also to be found included in the quartz. Now it is not possible to conceive any other way in which these two substances, quartz and feldspar, could be thus concreted, except by congelation from a fluid state, in which they had been mixed."

Our author having at length finished his arguments on the formation of the strata, draws the following general conclusion. "If it be by means of heat and fusion that veins of strata have been consolidated, then, in proportion to the degree of consolidation they have undergone from their original state, they should, ceteris paribus, abound with more separations in their mass. But this conclusion is not confirmed consistent with appearances. A stratum of sand-foliation does not abound so much with cutters or veins as a similar stratum of marble, or even a similar stratum of sand-stone that is more consolidated. In proportion therefore as strata have been consolidated, they are in general intersected with veins and cutters; and in proportion as strata are deep in their perpendicular section, the veins are wide, and placed at greater distances. In like manner, when strata are thin, the veins are many, but proportionally narrow.

"It is thus upon chemical principles to be demonstrated, that all the solid strata of the globe have been formed by means of heat and hardened from a state of fusion. But this proposition is equally to be maintained from propositions that are mechanical. The strata of the globe, besides being formed of earths, are composed of gravel, sand, and fragments of hard bodies; dies; all of which may be considered as in their nature simple: but these strata are also found composed of bodies which are not simple, but are fragments of former strata which had been consolidated, and afterwards were broken and worn by attrition so as to make gravel. Strata composed in this manner have been again consolidated; and now the question is, By what means?

"If strata composed of such various bodies had been consolidated, by any manner of concretion, from the fluidity of a dissolution, the hard and solid bodies must be found in their entire state, while the interstices between those constituent parts of the stratum are filled up. No partial fracture can be conceived as introduced into the middle of a solid mass of hard matter without having been communicated from the surrounding parts. But such partial separations are found in the middle of those hard and solid masses; therefore this compound body must have been consolidated by other means than that of concretion from a state of solution.

"The Spanish marble already described, as well as many consolidated strata of siliceous gravel, afford the clearest evidence of this fact. These hard bodies are perfectly united together in forming the most solid mass; the contiguous parts of some of the rounded fragments are interlaced together, as has already been observed; and there are partial shrinkings of the mass forming veins traversing several fragments, but perfectly filled with the sparly substance of the mass, and sometimes with parts of the stone distinctly floating on the transparent body of the spar. Now there is not in nature any known power, besides heat and fusion, by which these effects might be produced. But such effects are general to all consolidated masses, although not always so well illustrated in a cabinet specimen."

Thus the formation of the strata is supposed to be fully discussed; after which our author goes on to consider the means by which they have been elevated from the bottom of the ocean; for he looks upon it as an undoubted fact, that the highest points of our land have been for ages at the bottom of the ocean. "It is a truth unquestionable (says he), that what had been originally at the bottom of the sea, is at present the highest of our land. In explaining this appearance, therefore, no other alternative is left, but either to suppose strata elevated by the power of heat above the level of the present sea, or the surface of the ocean reduced many miles below the height at which it had subsided during the collection and induration of the land which we inhabit. Now if, on the one hand, we are to suppose no general power of subterraneous fire or heat, we leave to our theory no means for the retreat of the sea or the lowering of its surface. If, on the other, we are to allow the general power of subterraneous heat, we cannot have much difficulty in supposing either the surface of the sea to have subsided, or the bottom of the ocean in certain parts to have been raised by a subterranean power above the level of its surface, according as appearances shall be found to require the one or the other of these conclusions.

"The strata formed at the bottom of the ocean are necessarily horizontal in their position, or nearly so; and continuous in their horizontal direction and extent. They may change, and gradually assume the nature of each other so far as concerns the materials of which they are formed; but there cannot be any sudden change, fracture, or displacement naturally in the body of a stratum. But if these strata are cemented by the heat of fusion, and erected with an expansive force acting below, we may expect to find every species of fracture, dillocation, and contortion in those bodies, and every degree of departure from a horizontal towards a vertical position. The strata of the globe are actually found in every possible position: for found broken from horizontal, they are frequently found vertical; from continuous, they are broken and separated in every possible direction; and from a plane, they are bent and doubled. It is impossible they could have been formed by the known laws of nature in their present state and position. And here the apparent irregularity and disorder of the mineral regions are as instructive, with regard to what had been transacted in a former period of time, as the order and regularity of these same regions are conclusive in relation to the place in which a former state of things had produced that which, in its changed state, we now perceive.

"We are now to conclude, that the land on which we dwell had been elevated from a lower situation by the same agent which had been employed in consolidating the strata, in giving them stability, and preparing them for the purpose of the living world. This agent is matter actuated by extreme heat, and expanded with amazing force. If this has been the case, it will be reasonable to expect that some of the expanded matter might be found condensed in the bodies which have been heated by that igneous vapour, and that matter foreign to the strata may have been thus introduced into the fractures and separations of those indurated masses. We have but to open our eyes to be convinced of this truth. Look into the sources of our mineral treasures; ask the miner from whence has come the metal into his vein? Not from the earth or air above; not from the strata which the vein traverses. There is but one place from whence these minerals may have come; and that is, the bowels of the earth; the place of power and expansion; the place from whence must have proceeded that intense heat by which loose materials have been consolidated into rocks, as well as that enormous force by which the regular strata have been broken and displaced."

Our author is of opinion, that this action of heat is a great likewise evident from an inspection of the materials mechanical with which the veins are filled, as well as their various power re-fractures and irregularities; and informs us, that some of the great mechanical power must have been employed in filling these veins, as well as that necessarily employed the matter in making the first fracture and division. The successive irruptions of fluid substances into the veins, he says, is demonstrable from the mere inspection of the successive veins and their contents, it being very common to see irruptions three successive series of these operations; "all which of fluid matter may be perceived in a small fragment of a stone, which a man of science may examine in his closet, often better than by defending to the mine where all the examples are found on a large scale."

These fiery operations, he contends, are not to be accounted any way accidental, but as entirely natural to the globe, and remain at this day with undiminished force: and of this he brings a proof from the eruptions. tions of mount Ætna, informing us, that he has in his possession a table of Sicilian jasper, which evidently shows that this calcareous stone had flowed and been in such a state of fusion as lava is.

This subterraneous heat manifested in the burning mountains is the renovating power which the earth possesses within itself, and which prevents it from coming to an end by reason of the perpetual waste taken notice of in 22. "Volcanoes (says he) are natural to the globe as general operations; but we are not to consider nature as having a burning mountain for an end in her intention, or as a principal purpose in the general system of this world. The end of nature in placing an internal fire or power of heat, and a force of irresistible expansion in the body of this earth, is to consolidate the sediment collected at the bottom of the sea, and to form thereof a mass of permanent land above the level of the ocean, for the purpose of maintaining plants and animals. The power appointed for this purpose is, as on all other occasions where the operation is important, and where there is any danger of a shortcoming, wisely provided in abundance; and there are contrived means for disposing of the redundancy. These, in the present case, are our volcanoes.

"A volcano is not made on purpose to frighten superstitious people into fits of piety and devotion, nor to overwhelm devoted cities with destruction: A volcano should be considered as a spiral to the subterraneous furnace, in order to prevent the unnecessary elevation of land and fatal effects of earthquakes; and we may rest assured, that they in general wisely answer the end of their intention, without being in themselves an end for which nature had exerted such amazing power and contrivance."

The Doctor then goes on to show, that volcanoes are not proper for elevating land, unless placed at the bottom of the sea, where the contact of the water tends to close the orifice, and to accumulate matter upon the weakest part. An instance of this was given in the year 1707, when the burning island arose in the Mediterranean; and he confirms his theory by the great number of melted matters which are everywhere to be found in the strata, even of countries where no volcanoes exist at present. Examples are brought from the dykes of whinstone, as they are called in this country, and which he supposes to have been once in a state of fusion.

In order to avoid an objection which might here arise from the difference betwixt the appearance of our whinstone and the lavas of volcanoes, our author makes a distinction between such as have been erupted at the moment of explosion, and those which had been melted under a vast compresion of weighty materials, and at last exposed to the air after the lapse of a number of ages. "In the erupted lavas, those substances which are subject to calcine and vitrify in our fires, suffer similar changes when delivered from a compresion which had rendered them fixed, though in an extremely heated state. Thus a lava in which there is much calcareous spar, when it comes to be exposed to the atmosphere, or delivered from the compressing force of its confinement, effervesces by the explosion of its fixed air; the calcareous earth at the same time vitrifying with the other substances. Hence such violent ebullition in volcanoes, and hence the emission of so much pumice stone and ashes which are of the same nature. In the body of our whinstone, on the contrary, there is no mark of calcination or vitrification. We frequently find in it much calcareous composition, or the terra calcaria aerata, which had been in a whinstone melted state by heat, and had been crystallized by congealing into a sparry form. This is the cause of the differences between the erupted lavas and our whinstone, toadstone, and the Swedish trap; which may be called subterranean lavas."

All this time our author seems to have excluded from his system every idea of accounting for the origin of metals; though this would seem to be no less necessary than to account for that of whinstone. At Strange acclaff, however, we are informed that there are peculiar count of the productions in the mineral kingdom which are rare, origin of as being found only in few places; and of these he enterrates the diamond of the east, the platina of the west, and the tin of Cornwall, Germany, and Sumatra. "But all these substances (gold itself not excepted)," says he, "are to be considered as the vapours of the mineral regions condensed occasionally in the crevices of the land."

The last part of our author's dissertation contains System of the system of decay and renovation observed in the decay and earth. In this having again observed what had been already repeated over and over, that the land in the sea at present had been formed at the bottom of the sea, he proceeds to inform us, that, "at a gross computation, there may perhaps be a fourth part of our part of the solid land which is composed from the matter that had belonged to these animals. Now what a multitude of proceed living creatures, what a quantity of animal economy, from must have been required, for producing a body of calcareous matter which is interpenetrated throughout all the mists, land of the globe, and which certainly forms a very considerable part of the mass! Therefore, in knowing how these animals had lived, or with what they had been fed, we shall have learned a most interesting part of the history of the earth; a part which it is necessary to have ascertained, in order to see the former operations of the globe, while preparing the materials of the present land."

Before entering upon this subject, however, he still Gravel, thinks it necessary to consider some other of the sand, and component parts of the strata of our present earth, clay consisting. These are gravel, sand, and clay. Gravel, he tells us, is no other than stones worn round by their attrition in water; and finding them in the composition of our land, we must conclude, that in the former earth there had been operations of wind and water similar to those which we behold at present; and by which new gravel is continually prepared, as well as old gravel consumed or diminished by attrition upon our shores. Sand is no other than small particles of hard and solid bodies worn round by attrition. Clay is a mixture of different earths or hard substances in an impalpable state; and these substances are chiefly the siliceous and aluminoous earths. Others are occasionally mixed in clays; or perhaps always to be found in some small portion. But the great quantity of siliceous, argillaceous, and other compound substances, in form of earth or other impalpable sediment, corresponds perfectly with that quantity of these same substances which must have been prepared in the formation of so much gravel. gravel and sand, by the attrition of these bodies in the moving waters.

From these considerations our author tells us, that we have reason to conclude there had been in the former earth such operation as we see at present; and likewise that it had been composed of similar materials. The animals which had formerly existed, also appear by their remains to have been similar to what they are now; and it is also probable that their food had been derived from the same origin, viz. vegetables. There must therefore have existed in the former earth a world of vegetables, as well as a world of animals and an ocean. The existence of these he determines from the many specimens of fossil wood and petrified plants to be met with; and its profusion he thinks is evidenced from the quantities of mineral coal: of which he says, that "nothing can be more certain than that all the coaly or bituminous strata have had their origin from the substance of vegetable bodies that grew upon the land."

Lastly, when he comes to speak of the actual diminution of the earth we at present inhabit, he proceeds in the following manner: "Our land has two extremities; the tops of the mountains on one hand, and the sea-shore on the other. It is the intermediate space between these two that form the habitation of plants and animals. While there is a sea, shore, and a high ground, there is that which is required in the system of the world; take these away, and there would remain an aqueous globe, in which the world would perish. But, in the natural operations of the world, the land is perishing continually; and this is what we now want to understand.

"Upon the one extremity of our land there is no increase, nor any occasion of mineral substance. That place is the mountain top, on which nothing is observed but continual decay. The fragments of the mountain are removed in a gradual succession from the highest station to the lowest. Being arrived at the shore, and having entered the dominion of the waves in which they find perpetual agitation, these hard fragments, which had eluded the revolving powers natural to the surface of the earth, are incapable of resisting the powers here employed for the destruction of the land. By the attrition of one hard body upon another, the moving stones and rocky shores are mutually impaired; and that solid mass, which of itself had potential stability against the violence of the waves, affords the instruments of its own destruction, and thus gives occasion to its actual instability."

Having thus described very particularly the means by which the destruction of the present earth is going on, it is natural to inquire what progress has been made in the work. But in this neither ancient nor modern history give any assistance. The strait between Italy and Sicily he confesses to be no wider; the isthmus of Corinth to be no narrower; nor the rock on which the famous tower of Pharos was erected, either larger or smaller than before. The Palus Maeotis in the time of Polybius appeared to be very near filling up, as that historian informs us; and so it continues to appear at this day, without any apparent progress having been made in it. In short, the whole of our author's researches can produce nothing more than the loss of a small island in the mouth of the harbour of New Carthage, which Polybius says, existed in his time; and for which there is now only a rock under water. Our author therefore is obliged at last to own, that the quantity of decay in the rocks he speaks of, has either been too small for human observation, or, which is more probable, that no accurate measurement of the subject by which this quantity of decrease might be ascertained had been taken and recorded. "To sum up the argument, therefore (says he), we are certain, that all the coasts of the present continents are wasted by the sea, and constantly wearing away upon the whole; but this operation is so extremely slow, that we cannot find a measure of the quantity in order to form an estimate. Therefore the present immediate continents of the earth, which we consider as in a state of perfection, would, in the natural operations of the globe, require a space indefinite for their destruction. But in order to produce the present continents, the destruction of a former vegetable world was necessary; consequently the production of our present continents must have required a time which is indefinite. In like manner, if the former continents were of the same nature with the present, it must have required another space of time, which is also indefinite, before they had come to their perfection as a vegetable world.

"It is necessary, however, that the present land should be worn away and wasted exactly in proportion manner of new land shall appear; or conversely, that an equal proportion of new land should always be produced as the old is made to disappear. It is only required, that at all times there should be a just proportion of land and water upon the surface of the globe, for the purpose of a habitable world. Neither is it required, in the actual system of this earth, that every part of the land should be dissolved in its structure, and worn away by attrition, so as to be floated in the sea. Parts of the land may often sink in a body below the level of the sea, and parts again may be restored, without waiting for the general circulation of land and water; which proceeds with all the certainty of nature, but which advances with an imperceptible progression. Many such apparent irregularities may appear without the least infringement on the general system. That system is comprehended in the preparation of future land at the bottom of the ocean, from those materials which the dissolution and attrition of the present land may have provided, and from those which the natural operations of the sea afford.

"We have been now supposing, that the beginning of our present earth had been laid in the bottom of the ocean at the completion of the former land; but this was only for the sake of distinctions. The just view is this, that when the former land of this globe had been complete, so as to begin to waste and be impaired by the encroachment of the sea, the present land began to appear above the surface of the ocean. In this manner we suppose a due proportion of land and water to be always preserved upon the surface of the globe for the purpose of a habitable world, such as we possess. We thus also allow time and opportunity for the translation of animals and plants to occupy the earth. But if the earth on which we live began to appear on the ocean at the time when the last began to be resolved, it could not be from the materials..." Ear

Materials of the continent immediately preceding this which we examine, that the present earth had been constructed; for the bottom of the ocean must have been filled with materials before land could be made to appear above its surface.—Let us suppose, that the continent which is to succeed our land is at present beginning to appear above the water in the middle of the Pacific Ocean; it must be evident, that the materials of this great body, which is formed, and ready to be brought forth, must have been collected from the destruction of an earth which does not now appear. Consequently in this true statement of the case, there is necessarily required the destruction of an animal and vegetable earth prior to the former land; and the materials of that earth which is first in our account, must have been collected at the bottom of the ocean, and begun to be concocted for the production of the present earth, when the land immediately preceding the present had arrived at its full perfection. This, however, alters nothing with regard to the nature of those operations of the globe; the system is still the same. It only protracts the indefinite space of time in its existence, while it gives us a view of another distinct period of the living world; that is to say, the world which we inhabit is composed of the materials, not of that which was the immediate predecessor of the present, but of the earth which, in ascending from the present, we consider as the third, and which had preceded the land that was above the surface of the sea while our present land was yet beneath the water of the ocean. Here are three distinct successive periods of existence; and each of them is, in our measurement of time, a thing of indefinite duration. We have now got to the end of our reasoning; we have no data further to conclude immediately from that which actually is; but we have got enough. If the succession of worlds is established in the system of nature, it is in vain to look for anything higher in the origin of the earth. The result therefore of our present inquiry is, that we find no vestige of a beginning, no prospect of an end.”

VI. Though the theory of which we have now given such a large abstract is the most laboured and complete that hath yet appeared, it is still necessary to take notice of some other attempts, though perhaps less calculated to draw the attention of the public than that of Dr Hutton. One of these is by Mr Whitehurst; of which the following is the most material part of an abstract given by himself at the end of his work.

1. The globe we now inhabit was originally in a state of fluidity; and that not owing to any diffusive principle or subsequent solution, but to the first afflatus of its component parts. Whence it is presumed, that the earth had a beginning, and has not existed from eternity, as some have imagined; though the precise number of ages it has existed have not yet been actually determined.

The proof given by our author of this original fluidity of the earth rests entirely upon its oblate spheroidal form; which a fluid globe may easily be supposed to assume, though we cannot conceive how a solid one should do so.

2. “The fluidity of the earth, and the infinite divisibility of matter, evidently show, that the component parts of air, earth, water, &c. were uniformly blended together, none being heavier or lighter than another; whereby they composed an uniform mass or pulp, of equal consistence in every part, from its surface to its centre; consequently the new formed globe was unit for animal or vegetable life; and therefore it would seem extremely absurd to suppose that either the one or the other were created during the chaotic state of the earth, or prior to its being formed into an habitable world: therefore the presumption is great, that mankind were not created till the earth was become suitable to the nature of their existence.”

The proof of this position is laid down in the following manner. “It is a truth universally known, that from the component parts of the most dense bodies become solution of suspended in whatever menstrua they are dissolved; as metals in aqua-regia, silver in aquafortis, fats in water, and water in air. Nay, we may likewise add, that the component parts of mercury, in the act of distillation, become suspended in air, notwithstanding the specific gravity of the former is to that of the latter as 11,000 to 1 nearly. Such, therefore, are the consequences arising from the infinite divisibility of matter, none being heavier or lighter than another when thus reduced to their original elementary principles.”

3. “The component parts of the chaos were heterogeneous, or endowed with peculiar laws of elective attraction; whereby similar bodies are disposed to unite and form select bodies of various denominations, as air, water, earth, &c.: by means of these principles the chaos was progressively formed into an habitable world.

But the first operation which presents itself to our consideration is the oblate spheroidal figure of the earth, acquired from its diurnal rotation, and the laws of gravity, fluidity, and centrifugal force; which was no sooner completed, than the component parts began to act more freely, according to their affinities; hence the particles of air united to those of air, those of water to water, and those of earth to earth; and with their union commenced their specific gravities, and destroyed that uniform suspension which had hitherto prevailed throughout the chaotic mass. Thus commenced the separation of the component parts; for those of separation the greatest density began their approach toward the centre of gravity; and those of the greatest levity ascended towards the surface; therefore, as air is nearly 800 times lighter than water, the presumption is great, that the former was sooner freed from the general mass than the latter, and formed a kind of muddy impure atmosphere, surrounding the newly formed globe. Water, being next in levity, succeeded the air, and universally encompassed the earth in one vast ocean. In process of time these elements became perfectly pure and fit for animal life.

4. “The component parts of the chaos being thus divided progressively separated and formed into select bodies, formed by the following consequences necessarily ensued; namely, as the sun and moon were coeval with the chaos, the sun and solids could not uniformly subside from every part of the surface, and become equally covered by water; for as the separation of the solids and fluids increased, so, in like manner, the tides increased, and removed the former place to place without any order or regularity. Hence the sea became unequally deep; and these inequalities daily increasing, in process of time dry land appeared, and divided the waters which had hitherto hitherto prevailed universally over the earth. The primitive islands being thus formed, in process of time became firm and dry, and fit for the reception of the animal and vegetable kingdoms.

5. "Such appears to have been the natural order and progression of these things; consequently, as the sun was coeval with the earth, several days and nights must have preceded the sun's first appearance in the heavens, or its becoming visible on the fourth day, according to the scripture account.

6. "The atmosphere, sea, and land, being thus formed for the reception of the animal and vegetable kingdoms in successive periods of time, we have now to consider the order in which they were severally created. First, since it appears that the ocean became perfectly pure and fit for animal life before the primitive islands were formed, therefore we have endeavoured to prove from a series of undeniable facts (a), that marine animals were first formed; and being extremely prolific, they increased and multiplied to exceedingly as to replenish the sea from pole to pole. The ocean being thus stocked with inhabitants prior to the formation of the primitive islands, many of them became enveloped and buried in the mud by the continual action of the tides; particularly all the species of shell-fish, which are least able to defend themselves from such interments. Therefore, since the remains of marine animals are imbedded at various depths in the earth, from one to that of several thousand feet, and this in all parts of the world hitherto explored, they bear sufficient testimony, that these marine bodies were thus entombed at successive periods of time; and likewise that they were created prior to the primitive islands, and consequently prior to any terrestrial animals. It may be needlessly further to observe, that these beds of marine shells plainly evince, that they were generated, lived, and died in the very beds wherein they are found, and were not brought from distant regions by a flood or floods of water, as some people have supposed; consequently such beds were originally the bottom of the ocean.

7. With regard to the mountains, and indeed the continents also, Mr Whitehurst is of opinion, that they are the effects of subterraneous fire. His sentiments on this subject, however, are something singular; for he tells us, that "mountains and continents were not primary productions of nature, but of a very distant period of time from the creation of the world, when the strata had acquired their greatest degree of firmness and cohesion, and the siliceous matter had assumed a stony hardness."

Thus we have given a very particular account of all the theories of any note concerning the formation of the earth which have yet made their appearance. The deficiency of those of Burnet, Woodward, Whiston, and Buffon, must be exceedingly obvious even to the most superficial reader. They all assume only the powers of attraction and repulsion as agents; without considering that these two powers, or indeed any other two with which we are acquainted, could only have composed matters nearly similar to each other. If the original particles of matter are homogeneous, and endowed with similar powers, all the matter we see ought to be homogeneous also. But this is far from being the case. Some parts of it we see are exceedingly hard, others proportionally soft. The parts of some bodies attract each other violently; those of others have hardly any attraction for each other, but are separable by the smallest force. And though it should be granted that the powers of attraction and repulsion were originally different in different parts of matter, we have still to explain by what means the similar parts of matter found out each other in such a chaos as the earth originally was. This seems an insuperable difficulty in the systems of Drs Burnet and Woodward; and is equally, though less conspicuously so, in those of Whiston and Buffon.

Mr Whiston's system has another and very remarkable defect. He supposes the earth to have been originally a comet, and at a certain time to have become a planet; but he forgets to tell us by what means this comet was originally formed, or what kind of bodies the comets are. Yet certainly this theory of the comet was as necessary to his system as the theory of the earth itself; for all the substances now existing on the earth must originally have existed in the comet; and if the natural powers were known which made a distinction between one substance and another in the comet, we would also know those which distinguished terrestrial substances from one another. But though even this great deficiency should be overlooked, the supposition of a chaos or original confusion of any kind involves us in the greatest difficulties. If the whole surface of the earth consisted of a chaos of melted matter, we cannot reasonably think it would have appeared otherwise when cool than the lavas of burning mountains do just now; and this is a consequence of his system which Mr Whiston seems to have entirely overlooked.

Mr Buffon's theory is liable to the same difficulties of Mr Bute with the rest. He places his chaos in the sun; and therefore ought to have given a theory of the sun before he gave one of the earth. It ought also to have been shown for what purpose the sun was created when he had nothing to shine upon, or what probability there is that comets existed when there were no planets. His account of the formation of the planets by the stroke of a comet, is just within the verge of possibility; but his account of the formation of mountains by the motion of the winds and tides, is certainly inconsistent with the common principles of mechanics. Though it should be granted, that water can dissolve every terrestrial substance when vitrified by a heat 10,000 times greater than our hottest furnaces, as the sun must necessarily be; and though the water should let fall this matter as a sediment in what quantities and forms we think proper to imagine; it is impossible any of it could be thrown two or three miles above the surface of the water, in order to form those high mountains which are to be met with in different parts of the world. It is indeed very plain, that though by the motion of the waters their sediment might be collected in great heaps, it could never reach higher than their surface. The mountain,

(a) These proofs are afterwards considered, as here our author seems to be of the same opinion with Dr Hutton. mountain, once formed, must then be forever covered with water; for the sediment would take up precisely the same bulk when a mountain that it did when in a state of dissolution, and the water could never retire from it as he supposes. If the waters retired into vast subterraneous caverns, according to another of Mr Buffon's suppositions, they must have remained for ever in these caverns, from whence they could not have returned to effect those wonderful changes he attributes to them. But what in the strongest manner shows the fallacy of Mr Buffon's hypothesis, is the analogy he draws between mountains on dry land and islands in the sea. The islands, he says, are only the tops of great mountains in the ocean. If, therefore, the ocean had for a series of many ages covered the present habitable part of the world, as our author supposes, we should undoubtedly find many mountains upon the dry land, the tops of which had formerly been islands. But no such thing is to be found. There is not on earth a mountain with a top broad and flat like the island of Great Britain or Ireland, or even like islands of much less consideration.

These, and many other objections that will naturally occur to an attentive reader, show the extreme difficulties under which the hypothesis of Mr Buffon labours, as well as others. These difficulties arise, in the first place, from their assuming too few natural powers. Though it is certain that the powers of attraction and repulsion exist in nature, it is no less certain that there are many others. One very remarkable power entirely different from those of attraction and repulsion, may be called the power of assimilation or transmutation. By this, each animal, and each plant, changes the nutritious particles thrown into its stomach, or which it meets with in the earth, into a substance of its own peculiar kind. Thus, a stalk of wheat, by means of its roots, always affinates the nutritious particles of the ground into that particular grain we call wheat, and no other. This power naturalists have not been able to explain on the principles of attraction and repulsion, or any others with which we are acquainted; and therefore it may justly be called one of the primary laws of this earth at least, whether we understand the manner in which it operates or not.

Another power which seems to be diffused throughout this terraqueous globe, and common to all substances, water alone excepted, is that of multiplying themselves, or producing others of the same species. With regard to plants and animals, this is exceedingly evident; but may be disputed in the case of minerals. It is certain, however, that mines which have been exhausted, will in time be again replenished with ore; that spars and crystals, if broken or cut while their connection with the earth remains, will protrude a substance similar to the shell, as certainly as the wounded body of an animal will protrude flesh of a kind similar to what was taken away. The earth itself is capable of this multiplication. We see how it hath a tendency to ascend, and cover stones, &c., which lie a long time on its surface; and thus does this element, seemingly the most sluggish of all others, swallow up every thing that lies for some time undisturbed upon it. Hence we now meet with many monuments of antiquity below ground, which formerly were undoubtedly above it. Yet we have no sight from thence to conclude, that the height of the dry land above the water was greater at that time than what it is now. This multiplication of earth is chiefly owing to vegetation; which continually produces a new crust on the top, and thus tends to bury all such matters as fell upon the surface. This crust, however, does not produce a continual increase in the height of the dry land; for whatever quantity the vegetables add to the surface, they take from the under parts by the suction of their roots. Thus the ground becomes more porous, and the weight of ancient buildings, stones, &c., gradually forcing them downwards, they are at last buried underground to a considerable depth.

Hence it is easy to account for the sinking of the marine bodies that are to be found at different depths in the earth, even supposing them to have been left on shells at its surface by the deluge. M. Buffon's objection, drawn from the great quantities of them, seems but very weak: for it is certain, that marine animals, both of the crustaceous and other kinds, are found in the sea at this day in amazing quantities; and there is no bed of shells so large, that we can reasonably think it impossible for all the animals to have existed in it at once.

With regard to the strata, it seems undeniable that they may be produced from natural causes. Clay will sometimes be consolidated into stone; flint, marble, and limestone, are all found to grow naturally in the earth; so that we cannot draw any conclusion from the order in which we now find them. Though we find a bed of shells, then, in the heart of a solid rock, this makes no difficulty in the theory of the earth; since we know that the rock hath by some natural cause been consolidated around them. In fact, this is not so wonderful, as what is related by Mr Price in his Treatise of Minerals, Mines, &c., viz. That at the town of Redruth in Cornwall, "some labourers being put to clear and level the street for a pavement, they found a piece of hard stone in the ground, with abundance of common small pins of brass interperforated in and throughout the stone, in such manner and form, that all those who saw it afterwards were convinced it was not done artificially, but that the stone was formed and produced by petrifaction, subsequent to the time the pins were dropped into the ground. Doctor Plot, in his Natural History of Staffordshire, says, that near Newcastle-under-Lyne, there was found a stone with a man's skull, teeth and all, inclosed in it."—From these and other facts in some measure similar, this author concludes, that every earth or clay, in some places, may be converted into stone in process of time, at such a depth where it is undisturbed by being never lacerated nor molested, and also where it abounds with an uncommon quantity of juices of a lapidaceous quality; but this property being extenuated or destroyed, the earthy stones may not improbably again return to their primitive clay. Thus we see some forts of stone, when dug out of the ground and exposed to the air for a considerable time, do moulder again into earth, at least in appearance; while others, of an earth-like quality, are indurated, and become more compact and durable by lying above ground."

The theory laid down by Dr Hutton is of a different nature from the rest; and as it has been supposed to be directly contrary to revelation, merits a very particular consideration. The expression, however, with which which he concludes his dissertation, that "we can find no vestige of a beginning—no prospect of an end," might be supposed to relate only to the deficiency of our understandings or mode of inquiry, had he throughout the whole course of his work given a single hint of any materials from which the world was originally formed. In this he differs most essentially from the other theorists whom we have mentioned; for all of them suppose a chaos to have been originally created, from whence all the variety of substances we see at present have been formed. But as the Doctor makes no mention of anything prior to a world nearly similar to what we see just now, we must necessarily conclude that its eternity is a part of his creed. Now, that the world has not been eternal, may be proved from what he himself allows. Wherever we perceive a succession, we know that there must of necessity have been a beginning; but, according to our author, there has been a succession of worlds, by a kind of uncoth generation, similar to what would happen to the human race if a man was to descend immediately from his grandmother. Proceeding in this way, therefore, we must at last arrive at one great-grandmother of earths, from whence all the rest were descended; and of this one a theory was no less necessary than of any of her successors. This theory would have been the more difficult, as his great element cockle-shells and oysters would then have been absent, and the materials from whence they were afterwards to be produced must have been sought for.

Another argument, which evidently shows not only that the world is not eternal, but that some other power besides its own interfered with it originally, may be taken from the existence of animals and vegetables; both of which our author allows to have had a place throughout all his worlds. We see at present, that animals proceed from animals, and vegetables from vegetables; but the time must have been, when an animal was produced without a parent, and a vegetable without a seed. At this time the world must have been influenced by a power different from any it possesses at present; for no such power is now to be found in any part of the globe.

Lastly, the quantity of shells, great as it is, can by no means be reconciled with an eternal succession of worlds, or even with three; for, according to him, we must have three in order to have two habitable ones; viz., one lying at the bottom of the sea, another wearing away, and another beginning to emerge. Now he informs us, that only a fourth part of our land is composed of calcareous matter derived from marine animals*. But if one of the worlds has continued for a time indefinite, and consequently another lain at the bottom of the sea for an equal length of time, it must, instead of having a fourth part of its soil composed of calcareous matter at the time of its emergence, have been entirely composed of it, at least if we can credit what is said concerning the prolific nature of these animals. Mr Whitehurst informs us, that "it is not uncommon to take away a bed of shell-fish several fathoms in thickness; and though the places where they are fished for appear to be entirely exhausted, yet in the ensuing year there shall be as many found in all these places as before." Such an amazing increase must, in a time indefinite, especially if repeated for an indefinite number of times, have reduced the whole terraqueous globe to an heap of cockle-shells or other substances of that kind.

Our author is equally unfortunate in the very first step of his argument, where he says that the foil is only "the materials collected from the destruction of the solid land." He owns that all his earths produced taken place vegetables; but these must have had a foil wherein to grow before the first world had time to be destroyed. We are therefore here in the same dilemma with regard to the foil that we were before with regard to the foil vegetables; and as we are obliged to own the interference of a Superior power to produce the first vegetable, so must we also have recourse to the same power for the production of the foil on which it grew. All these considerations ought to have led the Doctor to a conclusion very different from that which he has drawn, and to have showed him that the beginning of the world was occasioned by a power which cannot possibly be investigated, because it lies without the bounds of Nature itself, and far beyond the reach of our faculties.

This objection indeed militates invincibly against all theories of the earth which seek to derive its original form from natural causes. The powers of attraction and repulsion we have already shown to be insufficient; and for though we should add to them those of fire and water, with all the train of solvents and precipitants which chemistry can afford, the deficiency will still be as great. It is true, that by means of chemistry we can imitate many of the natural operations, provided we have the proper materials: But this is the capital defect in all our theories of the earth. Whence came vast quantities of argillaceous earth into one place, of siliceous earth into another, of the materials for iron, silver, gold, &c. into the places where they are now found? With Dr Hutton indeed the whole seems to be composed of two materials, viz., calcareous earth and flint. But before he could justify this afflention, he ought to have produced from these two materials, at least a great number of the different substances with Dr Hutton, which the earth is replenished. But instead of this, he has recourse to natural productions, formed, as he says, by means which, in the hands of the best chemists, will prove insufficient to produce any thing like them.

In his account of the origin of calcareous matter, he tells us, it is to be derived entirely from the shells matter produced of marine animals; but he forgets to inform us whence these animals got their shells. There must have been some source of calcareous matter from which the first marine animal (for we have already seen that they could not have existed from eternity) derived its shell, and that independent of any other marine animal. Now we see at this day an abundant source from whence the shells of all marine animals may be derived, viz., the waters of the ocean, which contain a great quantity of calcareous matter. If we inquire whence these waters have it, we may say they take it up from the earth, part with it again in the form of shells, corals, &c. redissolve it, and so on. But if we will still inquire farther whence the earth itself had it, we must once more have recourse to that unsearchable and supernatural power to which we ascribed the origin of animals, vegetables, and the foil wherein they grow.

It is the foundation of Dr Hutton's theory, and indeed... deed seems now to be a favourite doctrine of most theorists, that the earth we inhabit has once been at the bottom of the sea; and it is thought to be a sufficient proof of this, that such vast quantities of marine shells are to be met with on dry land. Mr Whitehurst, after giving a long account of these shells, infers, among other things, that the "beds of fossil shells, which consist of one species only, and are not natives of the climate where found, but of very distant regions of the earth, evidently show that they were generated, and have lived and died in the very beds where found; and could not have been removed from their native climates by a flood or floods of water, with so much order as to form beds consisting only of one select species; and therefore all such beds must have been originally the bottom of the ocean."

On this mode of reasoning, however, we must observe, that no hypothesis can have a worse foundation than when it is built confessedly on our own ignorance. We know not, for instance, how a bed of fossil shells came into a certain place; therefore the whole world has been at the bottom of the sea for many thousand years, the climates have changed, or it has been eternal! Thus to unhinge the settled laws of nature for such trivial purposes, is certainly the greatest contradiction to true reasoning that can be imagined. But it is not only from a negative argument of this kind that we may refute this hypothesis; there is a much stronger one drawn from the marine productions themselves. It is certain, that there are substances very different from shells of any kind, which grow up from the bottom of the ocean, and in time indefinite ascend all the way to the surface, and there form islands. These are the coral rocks so common and so dangerous along the South Sea, and of which many of the islands there are formed. Now, how comes it to pass, that among all the marine monuments to be found on land we find no coral rocks growing there? The answer to this is obvious. The coral rocks require a vast length of time for their production, and are strongly fixed to the place where they grow; they cannot therefore be removed over land by any sudden flood or inundation, not even by a general deluge. Though it appears therefore, from the shells and other marine moveables, that what is now dry land has once been at the bottom of the sea, yet it is equally evident from the deficiency of these rocks, that it has not remained so for any length of time; and therefore, though we should by no means be able to explain all the appearances of fossil shells, we are not to admit a supposition which, from the circumstance just mentioned, cannot possibly be true.

With regard to these shells, however, we must remark, that it is in vain to attempt the explanation of every appearance; nor can any such thing be reasonably desired, even though we should acknowledge the deluge to be the universal cause. We know not, nor can we have any conception of, what might be accomplished by the mere mechanical motion of the waters in this case. Every one who has had an opportunity of seeing the effects of a violent land-flood, will be ready to own that it has performed things which a priori he would not have thought it could have done. But how infinitely must these effects be exceeded by one vast deluge, in which not only the dry land was softened by an incessant rain of six weeks, but the sea rose Earth. on all sides, and poured in upon it with all the moveable contents which the waters carried along with them?

That great numbers of shells already formed would be brought along with the waters of the ocean, is an assertion which can scarcely be denied; and we shall be inclined to look upon this number as exceedingly great, brought as if we consider the way in which it is most probable that long with the deluge came on. This was by the issuing out of waters* from every pore of the earth and bottom of the ocean, as well as by their descent from the clouds. In consequence of the former action, all the light bodies at the bottom of the sea must have been turned topsy turvy, and carried up no one can tell how far; at the same time that by the progressive motion of the waters they were carried to an unknown length over the land, and there deposited when the motion ceased.

This circumstance of itself will account for the appearance of vast numbers of shells and other marine productions on land; but there is another which must their forms be taken along with it, and will undoubtedly add greatly to its force. The unfathomable depths of the ocean are not the proper habitations of fish; and they are only found on shoals, or near the sea-coasts. At the time of the deluge, therefore, great numbers of the marine animals must have exchanged their ancient habitations for those where the water was more shallow; and of consequence would have abounded on the tops of mountains and other elevated places. Whether those animals whose exuviae are most plentifully met with on land have any locomotive power when full-grown, is uncertain; but whether they have or not, they are certainly of such minute sizes when young, that they may be floated to any distance by water. Thus therefore any kind of shell-fish may have reached any place in the globe; and Mr Whitehurst himself owns, that they can arrive to their full maturity in less than a year, as the beds which have been exhausted one year are found to be replenished the next. Now the flood, according to the Scripture account, continued long enough to allow time for their increase from spawn to their full size. It arrived at its full height in 40 days; and continued stationary for five months. It then began to decrease; but so gradually, that it was not till the first day of the tenth month that the tops of the mountains began to appear above the surface of the water; and it was not till towards the end of the eleventh that the tops of trees began to emerge. Here then we have time for beds of shell-fish to grow, live, and afterwards be left by the water; which in their mature state they could not follow, and thus to die in the places where they were generated.

Thus far we may safely argue with regard to the existence of large beds of shells on the surface of the earth; and it has already been shown how the earth would naturally cover and swallow them up to a considerable depth. But to account for the great depths at which we find them sometimes buried, several other things must be taken into consideration. One is, that would be the earth, by the continual rains at the time of the deluge, as well as by the issuing of the waters every where through its substance, must have been exceedingly soft and easily penetrated. The helpless animals of the wa- therefore, brought along with the ocean at its first irruption over land, would have been deep buried in the mud; and when we take into our account the pressure of a column of water four miles deep, it is impossible to say what effects this cause might have produced. They might, besides, have been accumulated in clefts of rocks, in hollows, valleys, and caves; and have been there consolidated by petrification and the growth of calcareous matter over them. And that something similar to this actually happens, we are very certain: for Mr Whitehurst informs us, that "the springs of Matlock-bath in Derbyshire, though extremely pellucid and friendly to the human constitution, are nevertheless plentifully saturated with calcareous matter, which readily adheres to vegetables and other substances immersed in their streams; and thus, by a constant accretion, large masses of stone are gradually formed. The banks on which the bath-houses stand, and likewise the buildings themselves, are mostly composed of such materials."—Now, had these waters directed their course over a bed of shells, through a burying-place, or over a field of battle, it is evident that they would have inclosed a great number of shells, human and horse bones, heads of lances, swords, or even the more modern weapons of guns and pistols; which, to a curious naturalist, might have furnished an argument for the antiquity of these latter weapons. If therefore we see that bodies at this day may be so easily imbedded in stone, why should we pretend to set bounds to the petrifications which may have happened in the course of more than 4000 years, a period far beyond the reach of our most ancient histories.

It is not meant, by what we have just now said, to explain all the appearances of fossil shells or bones from the deluge as a general cause. This cannot be done unless we knew all the circumstances. The following facts, however, may be looked upon as authenticated:

1. That when the waters overwhelmed the land, great numbers of marine animals were carried along with it. 2. That during its continuance most of those which have any locomotive power would choose rather to dwell over land than in places which had formerly been their residence. 3. That while the waters remained on the earth, all kinds of marine animals would breed over land in their natural way; and such as could not follow the waters in their retreat, would be left to die on dry land, which must have been the case particularly with shell-fish. 4. These impotent animals, which have little or no power of locomotion, would by the pressure of a column of water four miles high be buried to depths unknown. 5. After the retreat of the waters, those which had been lodged in hollows or clefts, or perhaps diffused through the substance of many soft strata, might by some petrifying quality in the stratum be so consolidated along with it, as afterwards to form one entire rock. This is evident, not only from the example of the Matlock-springs, but more so from that of the pins found in the flint at Red-Ruth in Cornwall, from the petrified skull mentioned by Dr Plett, and many others; of which we shall mention the following from Mr Whitehurst:—

"The strata of limestone in Derbyshire, and in many other parts of England, abound with the exuviae of marine animals, or the impressions of them in the solid substance of the stone; and we have likewise several instances related by authors of the bones of terrestrial animals, and also of wood, having been found enveloped in strata of stone. A complete human skeleton, with British beads, chains, iron-rings, braids of bridles, were dug up in a stone-quarry near the Earl of Widrington's seat at Blankney in Lincolnshire.—Human bones and armour, with Roman coin, fibulae, &c., were found in a stone-pit in the park at Huttonton in Norfolk, supposed to have been buried after a battle.—In the mountains of Canne, half a league from Meaftrick, were found the remains of a crocodile well preserved in a stratum of sandstone.—The remains of a crocodile were also found in a stratum of stone at Blenheim.—The beds of argillaceous stone, &c., incumbent on coal, also contain a great variety of figured fossils representing different parts of the vegetable creation."

From all these examples it is plain, that the lapidescient power which the earth possesses is capable of incorporating bodies with stone to an unknown thickness, so that in whatever situation therefore we find those fossil bodies, we have no reason to say that the deluge is not ultimately the cause of their being there; because its substances power in overpowering the earth with them, in burying them in it, or forcing them into clefts and caverns, is altogether unknown; and before it is denied that the deluge could be the cause of such appearances, it is unnecessary to show all that it really could do, which is evidently impossible; so that here our speculations must ultimately rest.

We shall only add one other fact which must certainly have taken place at the deluge. At that time human bones are generally thought to have been very full of inhabitants. These, as well as all the inferior animals, would naturally fly from the approaching danger. This would assemble them in great numbers in such places as appeared to afford security; and here they would all perish together. This will account for the vast heaps of bones found in certain parts of the world, as in the rock of Gibraltar, Dalmatia, &c., and the natural petrificative power of the earth may account for their consolidation. The slaughters which mankind have made of one another may indeed account for many of these appearances. When we read in history of 40,000, 50,000, or 100,000 men being killed in a battle, we never think of the space their bones would occupy when thrown into a heap; nevertheless, we are assured that the bulk of these remains must be very great. Tamerlane, with an army of 800,000 men, filled up the harbour of Smyrna by causing each of his soldiers throw one stone into it; and when Marius defeated the Cimbri, the bones of the slain were so numerous, that they were used for a long time as fences for vineyards. Had these been collected into one heap, and afterwards consolidated by petrificative matter, they would undoubtedly have occupied a very considerable space. What then must have been the case, when every man, nay every other terrestrial creature, died at once? Taking all these things into consideration, it must surprise us that the collections of fossil bones are not more numerous than we find them.

Thus we see, there is on the one hand no reason for denying that the deluge has been the cause of all the fossil appearances we perceive; and on the other, that there there is the strongest reason for denying that the land we inhabit has been for a length of time at the bottom of the sea. Dismissing therefore this part of Dr Hutton and Mr Whitehurst's theories, we shall now proceed to consider that of the former, where he investigates the formation of the strata. These, he says, could not be formed by aqueous solution. That they could not be so originally, we readily grant; but that they have preserved themselves from decay, transformed themselves into one another, and repaired their waste by this means, is absolutely certain. The Doctor indeed gives up his own argument; for he tells us, that "if flint can be produced by crystallization from water or any aqueous solution, then may his assertions concerning the consolidation of the strata be denied." But Mr Bergman affirms us, that he actually did produce flint by allowing a quantity of fluor acid to stand for two years on some powdered quartz; and this is more than any chemist can pretend to do by the violent heat of fusion, to which Dr Hutton has recourse on all occasions. We do not pretend, however, to say, that the different strata of earth have been formed originally by aqueous solution. For this we must have recourse to the power already mentioned, and for want of which neither Dr Hutton's theory nor any other can support itself. But though the strata were originally formed by Divine power, they are certainly preserved, repaired, and changed by natural causes; of which aqueous solution is a principal, though not the only one.

The said experiment of Mr Bergman's entirely overthrows the Doctor's objection (no. 39.) relating to the penetration of wood by filaceous or flinty matter. It shows, that the matter in question may be dissolved, and in no very long time deposited in its proper form; so that had Mr Bergman enclosed a bit of wood in his bottle which produced the flint, there is no reason to doubt that it would have been so penetrated by the filaceous matter as to be completely flintified (to use Dr Hutton's word) by the end of the two years.

The imposibility which our author talks of, of flinty substances being found insulated in the midst of beds of chalk, is likewise thus removed. But if we view his own account of the petrification of wood by the action of melted flint, what mortal in his senses can give him credit? It exceeds the power of a glas-house furnace to melt flint by itself: how is it possible, then, that the combustible substance of wood should bear to be filled with this dreadful fluid without being burnt? The operation being performed under water, will not answer the purpose: for wood may be reduced to charcoal, by the heat of a burning-glass, under water; and a red hot iron, thrown into a wooden vessel full of water, will burn a hole in the bottom. Dr Black, who mentions this circumstance in his Lectures, very justly observes, that the steam which is produced keeps off the water until the iron has produced its effect. Must not the same effect take place at the bottom of the sea, even granting, what Dr Hutton never can prove, that flint, by any degree of heat whatever, can be reduced to such a state of tenacity as to be capable of penetrating wood like an anatomical injection? Here indeed he may tell us, as on another occasion, that

† See no. 46. the compression of the water is insuperable. But if this be the case, how comes it to pass, that not only this insuperable compression, but an additional one (no less than the vast loads of earth which compose the continents of Europe, Asia, Africa, and America), has actually been overcome, and these immense tracts thrown up from the bottom of the ocean, by the force of fire which could not consume a piece of wood?

To suppose that, by any compulsion whatever, the element of fire, when applied to a combustible body, should be prevented from destroying its texture, is certainly without the least foundation; and yet upon entirely this and similar suppositions proceeds the whole of the reasonable Doctor's theory. He differs from those who maintain the volcanic theory, in supposing that fire may work underground in such a manner as to perform none of its common effects, or indeed none but such as are agreeable to his own hypothesis. Thus fire, working at the bottom of the sea, or at an unknown depth under it, shall not burn wood; it shall not extricate the fixed air from calcareous matter, but melt it sometimes into one substance and sometimes into another; it shall not dilute the most volatile substance, nor in short perform any effect which we ever saw performed by fire: and all this, it seems, is demonstrable by the mere inspection of fragments of stones in a closet, without paying the least attention to the operations of nature abroad.

Though it must be very evident that a theory built on such extravagant principles cannot support itself, from mine, we must still take notice of the proofs he adduces from the mineral crystallizations, &c. On this subject it may be observed, that there are various ways by which substances can be crystallized or assume regular figures.

1. The most common is by solution in a large quantity of water, from which the bodies are deposited by cooling, and form distinct and regular crystals.

2. By fumes may solution in no greater quantity of boiling water than be crystallized into large masses, as is the case with alum.

3. By slow evaporation, as is the case with vitriolated tartar and some other salts.

4. By efflorescence, when a saline fluid is mixed with a quantity of earthy matter, and kept moist for some time. Of this we often have an example in moist cellars, or other damp places, where we shall see part of the walls covered with a fine, downy, saline matter. In salt-butter also we shall frequently see the same appearance; where the salt floats into small picles, though in the common way it crystallizes in cubes.

5. By sublimation, as in the case of flowers of benzoin, of corrosive mercury, cinnabar, sal ammoniac, orpiment, &c. &c.

6. By the meeting of two substances in an aerial form, as alkaline and fixed air. By the attraction of fixed air from the atmosphere or otherwise, as is the case with alkaline salts when long exposed to the common air, or for a shorter time to a stream of pure fixed air.

7. By precipitation, as in the arbor Diana and other metallic vegetations.

8. By means of acids. Thus the residuum of Glauber's spirit of nitre, if the distillation has been performed with an excess of acid, will shoot into beautiful ramifications like branches of trees.

9. By fusion, as in regulus of antimony and other metals, sulphur, &c.

Now of all these different ways by which crystallization may be effected, Dr Hutton has chosen only the last; and this he obstinately carries through the whole system. system of nature, whether reasonable or not. His argument against any other mode is chiefly built upon the insolubility of certain substances; but this argument has failed in one very remarkable instance, viz., that of flint, which has been produced by aqueous solution. Another instance he brings, no. 42, of "marmor metallicum, consisting of terra ponderosa faturated with vitriolic acid, a fulblance insoluble in water." Now though this substance, when once it is formed, may be termed absolutely insoluble; yet the fact is certain, that it may be formed by aqueous solution and crystallization; and we have done so by the following process: Let terra ponderosa be formed into an heap of sulphur by any of the common methods; dissolve the mass in water; filter the solution, and expose it to the air in a vessel kept in a gentle warmth; the phlogiston of the sulphur will gradually fly off; the acid attach itself to the earth; and in a day or two a great quantity of fine crystalline spicule will be formed, which are a true marmor metallicum.

Thus we learn how many bodies, naturally insoluble, may yet be formed by aqueous solution by reason of the solubility of their component parts. Sulphur is soluble by calcareous earth and by terra ponderosa, and makes these substances soluble in much greater quantity than they naturally are. By the decomposition of the solution of terra ponderosa, marmor metallicum is produced; and by decomposing the other, felspar or alabaster. This last substance Dr Hutton has not thought proper to mention, though huge masses of rock are composed of it; and it is incapable of fusion without being destroyed. Its regular figures, however, afford us a fine example of that species of crystallization which proceeds from precipitation or accretion. The felspar is a substance very little soluble in water; yet by the perpetual deposition of small quantities, we see that beautiful and regular crystals are formed; and hence we learn another important fact, viz., that in order to form these crystals, it is not always necessary that the whole of the substance should be dissolved in water at once, though this is the case with our artificial crystallizations. The largest and most transparent crystals, and even the most insoluble in water, may have been formed by the continual accretion of crystalline matter from an aqueous solution; and thus they may appear in any cavity whatever; for as there is no mineral substance impermeable to water, it evidently follows that no cavities can be impermeable to it.

Among his other insoluble substances Dr Hutton mentions fluor and calcareous spar. But as we know that one of the component parts of fluor is calcareous earth, naturally soluble in water, it is only necessary to suppose a calcareous water like that of Matlock to meet with fluor acid; and as great quantities of fluor would be produced as there are at present of calcareous stone.

The same thing may be said of calcareous spar.—We know that fixed air will precipitate calcareous earth from water, or redissolve it after it has been precipitated, according to its quantity. The formation of spars, therefore, from calcareous matter dissolved in water and fixed air, may easily be understood; and we know that there is no water which does not contain some quantity of calcareous earth. Of fixed air there is always great plenty in the bowels of the earth; and according to the quantity uniting itself with the dissolved calcareous earth, either chalky concretions or crystalline bodies will be produced. If fire were applied to this calcareous matter in order to fuse it, an emission of the fixed air would be the certain consequence; and without this we have not the least evidence that calcareous earth ever did or could undergo any fusion by heat.

With regard to the mineralization of metals by fusion of the phlogiston, as in the case of pyrites, we cannot pretend to explain them particularly; though it was certainly incumbent on the Doctor to have formed these bodies, solution, or to have produced something like them, by fusion, before he determined that they were formed originally in this way. It is easy, however, to see how the calx of a metal may meet with sulphur in the earth. We know that sulphur is soluble by alkali, by terra ponderosa, or by calcareous earth. By exposing this solution to fixed air, part of the sulphur is separated, and may unite with the metallic earth, or any other thing with which it has an affinity. The crystallizations of sulphur artificially united with metals have not indeed been examined; but before we affirm that a metal is mineralized by fusion with sulphur, we ought to perform something like it artificially, which never has been done.

As to the invincible argument no. 43, where our author triumphantly challenges his adversaries to show how petro-filix, pyrites, and cinnabar, can be dissolved in water; it may be replied, that Mr Bergman has decided the matter against him with regard to the first, by his remarkable experiment of making flint; the second is as yet undecided; for no chemist has been able to make pyrites either by solution or fusion. The third is likewise decided against our theorist; for Dr Lewis has shown that cinnabar may be prepared by solution of sulphur as well as in the dry way by sublimation. We have only to suppose therefore that a calcareous solution of sulphur pervaded this mineral, while a number of particles of quicksilver were dispersed through it; in which case the latter, attracting the sulphurous particles, would form the cinnabar in question.

Our author's argument (no. 44) from metals being found in their perfect state, is very inconclusive. The found native iron he speaks of, is by many thought to be fictitious; and as to the small bits of other metals sometimes found native, they rather make against him than otherwise: for had they been melted, all the rest of the matters around them must have been melted also; in which case the superior weight of the metals would have carried them to the bottom of the melted mass, there to unite as in a common furnace.

His arguments concerning bituminous bodies are equally unfortunate with the rest. That coal is derived from wood has been the opinion of very learned men, particularly Dr Black. The argument, however, is only this, that sometimes we see coals with woody fibres, plainly indicating their vegetable original. But this would hold equally with regard to stones; for we often see wood penetrated with stony matter, while its fibrous texture still remains. In this case therefore we might as well suppose that stones are derived from wood as that coals are so. A decisive proof that coals are not produced by fusion, is, that a living toad has been taken out of the heart of a solid piece of coal. This is similar to the entombment of the fishes called pholades in the heart of flints; and as, in the latter case, we believe that the stone has concreted round the fish, so we have the same reason to believe, in the former, that the coal had consolidated round the toad. All that we can say therefore is, that coal is formed by a natural, and not very tedious process, unknown to us; but that this process certainly is not fusion. His proof no. 47 is altogether inconclusive; for we have already seen that flinty substances and marmor metallicum may be produced by aqueous solution.

Thus we have seen, that, contrary to our author's hypothesis, the world has undoubtedly had a beginning; that our dry land has not, for ages, been the bottom of the sea; that we may reasonably suppose the deluge to have been the cause of all or most of the fossil appearances of shells, bones, &c., we meet with; that our author has erred in denying to aqueous solution the effects which experience has shown it capable of producing, and in ascribing to fusion effects which experience doth not warrant; and that his theory, far from having any foundation in chemistry, is directly contradicted by that science. It would be tedious and disagreeable to proceed farther in adverting on a theory so truly unphilosophical, however elaborate and ostentatious in a display of facts: we shall therefore content ourselves with taking notice of one other objection to his doctrine, of which he himself has been aware, with the answer he has given. The objection is, That there are sometimes found flinty and crystalline bodies containing water: it seems therefore a contradiction to say that such were produced by fusion. To this the Doctor replies, "It must not be here objected, that there are frequently found flinty crystals and amethysts containing water; and that it is impossible to confine water even in melted glass. It is true, that here, at the surface of the earth, melted glass cannot, in ordinary circumstances, be made to receive and inclose condensed water; but let us only suppose a sufficient degree of compression in the body of melted glass, and we can easily imagine it to receive and confine water as well as any other substance. But if, even in our operations, water, by means of compression, may be made to endure the heat of red-hot iron without being converted into vapour, what may not the power of nature be able to perform?"

On this reply we shall only observe, that the truth of this hypothesis, as well as of all other parts of it, may easily be put to the trial by those who have any of these crystals in their possession. Let one of them be broken, and the water it contains examined. If the crystal has been formed by fusion at the bottom of the sea, as Dr Hutton supposes, it will be salt; if otherwise, fresh. As to his doctrine concerning subterraneous heat and volcanoes, there will be occasion to consider it under the article Volcano.

We must now take into consideration those remarkable changes which are supposed to have taken place on the globe, in such a manner as entirely to have altered its appearance. These, however, do not appear to have any solid foundation. Changes, no doubt, have happened in particular parts; new islands have been thrown up from the bottom of the sea by the force of subterraneous fire, and others have been swallowed up. But these appear to be merely the effects of volcanoes, which are common in many parts of the world; and we are not warranted to conclude, because we see a small volcanic island arise, and another swallowed up, that this has been the case with the whole habitable world.—An imperfect theory hath indeed been suggested by Sir William Hamilton, Mr Brydone, and others, concerning the use of volcanoes and subterraneous fires; from whence it might seem probable, though they do not indeed say so in direct terms, that all the dry land was originally thrown up from the bottom of the sea by the force of these fires. Sir William Hamilton, in his letter to Dr Maty, broaches this theory in the following words. "I am myself convinced, that the whole circuit, so far as I have examined, within the boundaries marked in the map (extending at least 50 Italian miles in length, and 30 in breadth where broadest), is wholly and totally the production of subterraneous fires; and that most probably the sea formerly reached the mountains that lie behind Capua and Caetara, and are a continuation of the Apennines. If I may be allowed to compare small things with great, I imagine the subterraneous fires to have worked in this country under the bottom of the sea, as moles in a field, throwing up here and there a hillock; and that the matter thrown out of some of these hillocks formed into settled volcanoes, filling up the space between the one and the other, has composed this part of the continent, and many of the islands adjoining.

"From the observations I have made upon Mount Etna, Vesuvius, and the neighbourhood, I dare say that, after a careful examination, most mountains that are, or have been, volcanoes, would be found to owe their existence to subterraneous fire; the direct reverse of what I find the commonly received opinion. Nature, though varied, is certainly in general uniform in her operations; and I cannot conceive, that two such considerable volcanoes as Etna and Vesuvius, should have been formed otherwise than every other considerable volcano of the known world. I do not wonder that so little progress hath been made in the improvement of natural history, and particularly in that branch of it which regards the theory of the earth: Nature acts slowly; it is difficult to catch her in the fact.

"From repeated observations I have made in the neighbourhood of Vesuvius, I am sure that no virgin soil is to be found there; and that all is composed of different strata of erupted matter, even to a great depth below the level of the sea. In short, I have not any doubt in my own mind but that this volcano took its rise from the bottom of the sea; and as the whole plain between Vesuvius and the mountains behind Caetara, which is the best part of Campagna Felice, is (under its good soil) composed of burnt matter, I imagine the sea to have washed the feet of those mountains, until the subterraneous fires began to operate, at a period certainly of a most remote antiquity.

"The soil of the Campagna Felice is very fertile; I saw the earth opened in many places. The stratum of good soil was in general four or five feet thick; under which was a deep stratum of cinders, pumice, fragments of lava, and such burnt matter as abounds near Mount..." Mount Vesuvius and all volcanoes. The mountains at the back of Caetra are mostly of a sort of limestone, and very different from those formed by fire; though Signor Van Vitelli, the celebrated architect, has assured me, that in the cutting of the famous aqueduct of Caetra through these mountains, he met with some foils that had evidently been formed by subterranean fires. The high grounds which extend from Castel-a-Mare to the point of Minerva towards the island of Caprea, and from the promontory that divides the bay of Naples from that of Salerno, are of limestone. The Plain of Sorrento, that is bounded by these high grounds, beginning at the village of Vico, and ending at that of Malfa, is wholly composed of the same sort of tufa as that about Naples, except that the cinders or pumice-stones intermixed in it are larger than in the Naples tufa. I conceive, then, that there has been an explosion in this spot from the bottom of the sea. This plain, as I have remarked to be the case with all foils produced by subterranean fire, is extremely fertile; whilst the ground about it, being of another nature, is not so. The island of Caprea does not show any signs of having been formed by subterranean fire, but is of the same nature as the high grounds last mentioned; from whence it has been probably detached by earthquakes, or the violence of the waves. Rovigliano, an island, or rather a rock, in the bay of Castel-a-Mare, is likewise of limestone, and seems to have belonged to the original mountains in its neighbourhood: in some of these mountains also, there are petrified fish and fossil shells, which I never have found in the mountains which I suppose to have been formed by explosion. Bracini, however, in his account of the eruption of 1613, says, that he found many sorts of fish-shells on Vesuvius after that eruption; and P. Ignatius, in his account of the same eruption, says, that he and his companions picked up many shells likewise at that time upon the mountain: this circumstance would induce one to believe, that the water thrown out of Vesuvius during that formidable eruption came from the sea.

This may serve to show upon what grounds the volcanic theory stands: but though we should admit it in its utmost extent, the theory of the earth can receive but very little affluence from it. Sir W. Hamilton himself does not say that all the mountains have been volcanoes, or that all the soil throughout the different quarters of the world hath been thrown up from the bottom of the sea. If, therefore, there remains but one mountain in the whole world which never was a volcano, we shall be as much difficulty to account for the production of that one, as though there were ever so many; and at any rate our theory will be absolutely useless, because what will account for the origin of that mountain, will also account for the origin of others. If we go a step beyond our author, and say, that there are no mountains whatever that have not been originally volcanoes, but that all the dry land is the production of subterranean fire, our difficulties are so far from being removed, that they are greatly increased. The lavas and volcanic ashes, though in time they become covered with an exceedingly fertile soil, remain absolutely barren for a great number of years; infomuch that, by the adopters of the volcanic hypothesis, the period at which Moses fixes the creation is reckoned by far too late to have given time for covering the many lavas of Italy and Sicily with the depth of earth they just now have upon them. The whole world therefore must have remained for many ages in a state of absolute sterility; and by what means or in what corner of the world vegetation first began, remains to be inquired into.

Without entering further into the theories either of Sir W. Hamilton or any other person, it is easy to see, that all of them are insufficient to solve the difficulties mentioned n° 11. It is common to account for the spheroidal figure of the earth, from the greater centrifugal force of the equatorial parts than of the polar ones; but this explication can by no means be deemed sufficient. The globe we inhabit is composed of two very different kinds of matter, earth and water. The former has a very considerable power of cohesion, besides the gravitating power; the latter has very little cohesion, and its parts may be separated from each other by whatever will overcome its weight. It follows, therefore, that the solid parts of the earth, resisting, by their cohesion, the centrifugal force more than the water, ought not to dilate too much. The waters of the ocean therefore ought, about the equator, to swell up and overflow the land; and this they ought to do at this present moment as much as at the first creation. That this ought to be the case, is evident from the phenomena of the tides. It is not to be doubted but that the attraction of the moon affects the solid earth as well as the sea; but because of the greater cohesion of the former, it cannot yield as the ocean does, and therefore the waters are raised to some height above it. Mr. Whitehurst and others indeed solve this difficulty by supposing the earth to have been originally fluid. But this is arguing in a circle; for if we declare them to prove this original fluidity, they will do it by the spheroidal figure of the earth; and if the cause of the spheroidal figure is required, they refer us to the original fluidity. See Whitehurst's Inquiry.—The height to which the waters would have covered the equatorial parts by the centrifugal force, must have been equal to the depression at the poles; which, according to M. Buffon, is about 17 miles; according to other mathematicians, 25 or 26 miles.

The other difficulties are so totally inexplicable, that Buffon, who seems to exert himself as much as possible in order to remove them, is obliged at last to own, that the earth is in a perishing state; that the hills will be levelled, and the ocean at last cover the whole face of the earth; a prophecy which wears no very favourable aspect to the inhabitants of this globe.—For these imaginations, however, there does not seem to be the smallest foundation in nature. The mountains have continued what they were, from the earliest accounts of time, without any signs of decay. Mount Etna, besides the waste common to it with other mountains, hath been exhausting itself by throwing out incredible quantities of its own substance; yet it still seems to be what it was called by Pindar 2200 years ago, the pillar of heaven. It seems extremely probable, therefore, that there are powers in the system of nature which tend to preserve, and are capable of counteracting those which tend to destroy, the mountains; and perhaps... haps the late discovery concerning the attraction of mountains may some time or other throw some light on the nature of these powers. See Mountain.

The like may be said of the isthmuses or narrow necks of land which in some parts of the world join different countries together; such as the isthmus of Darien, of Suez, the Morea, &c. Though the ocean seems to beat on these with great violence, they are never diminished in bulk, or washed away, as, according to Buffon's theory, they ought to be. It is plain, therefore, that there is in nature some power by which these narrow necks of land are preserved from the fury of the ocean; for history does not afford one instance of any neck of land of this kind being broken down by the sea.—It seems impossible to solve the difficulties with regard to the strata and shells by any other means than supposing, that there are in the terrestrial matter several distinct powers, by which the strata of any particular kind are occasionally transformed into others; and that the shells and other marine bodies were originally deposited on the surface by the deluge. The volcanic hypothesis, by which some attempt to account for the appearance of these bodies, will in no shape answer the purpose. By the explosions of a volcano, shells, mud, sand, &c. might be indiscriminately thrown up, and scattered irregularly about; but we could never find the large beds of shells which are frequently to be met with of a considerable extent in different parts of the earth.

With regard to any degree of certainty, it is scarcely to be hoped for on this subject. The common notion of the earth's being originally a chaos, seems neither to have a foundation in reason, nor in the Mosaic account of the creation. It is surely inconsistent with the wisdom ascribed to the Deity, to think that he would create this visible system in confusion, and then employ it to put itself in order. It seems more probable, that the earth was originally created with the inequalities of surface we see it have, and that the natural powers for preserving it were afterwards superadded. Thus, according to Moses, the first natural agent created, or produced, by directing matter to move in a certain manner, was light. This, we know, was absolutely necessary for the evaporation of the water which took place on the second day. Moses tells us, that the earth was originally covered with water: and we see a natural reason why it should be so; namely, that the evaporation by the atmosphere might more easily take place. When this was done, there being then no more occasion for the waters in that diffused state, they were commanded to retire into the place appointed for them, and thus formed the ocean. Whether this was done by the action of gravity then first taking place, or by any other means, we have it not in our power to know, nor will our speculations on this subject probably be attended with much benefit. We see, however, that the Mosaic account of the creation is perfectly consistent with itself, and free from those difficulties with which other systems are clogged. It is impossible to show, how, by any natural power, a confused mass of matter, such as the chaos of the ancient poets, of Drs Burnet and Woodward, the hollow globe of Mr Hutchinson, the comet of Mr Whiston, or the vitrified matter of M. Buffon, could put itself in the order in which we see it. The sacred historian simply tells us, that God created the heavens and the earth; that the heavens gave no light, and the earth was covered with water. He first commanded the light to shine, then the air to take up what quantity of water he thought proper for the purposes of vegetation. After this, the dry land was made to appear; and the different powers of vegetation already taken notice of were given to it. Next the sun and moon were created as subordinate agents, to divide the light from the darkness, &c. Then followed the formation of animals and of man.

According to this account, it would appear, that what we call the laws of nature, were given to preserve the earth in that shape which the Deity thought proper to give it originally by his own power; and by no means to form it in any particular way, much less to put it out of the form which he had already given it: and thus the world, according to the best accounts we have, is very little altered in its appearance; and, according to what we can judge, will continue unaltered for ever, unless the Creator thinks proper to interpose in such a manner as to supersede all the laws he hath given it, and change it into some other form.

From some observations of Sir W. Hamilton and others, objections have been drawn, as hath been already mentioned, to the Mosaic chronology. These objections are in substance as follows. In pits, and other natural and artificial openings of the ground, in the neighbourhood of Vesuvius and Etna, several beds of lava have been discovered at considerable depths below each other. These beds of lava in some places are covered with successive strata of vegetable mould. From this disposition of materials, Sir William concludes that the world must have been created at a much more remote period than is generally believed. The different strata of lava found below ground, he observes, must have proceeded from an equal number of eruptions from the mountain; and such of them as are covered with vegetable soil must have remained at least 1000 years on the surface before they could acquire a soil sufficient for the purposes of vegetation. Ten or twelve successive strata overlaid with soil have already been discovered in the bowels of the earth; and it has been strongly asserted, that, by digging deeper, many more might have been found. Now, allowing 1000 years for each stratum of lava, which the supporters of this theory affirm to be too little, the antiquity of the earth cannot be less than 12,000 years, which is more than double its age according to the Mosaic account.

The principal fact in this theory is, that 1000 years are necessary to the production of a soil sufficient for the nourishment and growth of vegetables upon volcanic lavas. This notion is confirmed by a conjecture of the Canonico Recupero, that streams of lava in Sicily have lain for centuries without acquiring a vegetable mould; and by some obscure accounts, that these lavas have proceeded from eruptions of Etna above 1000 years ago. The following considerations, however, will render this theory at least extremely dubious.

Sir William informs us, that some lavas are very solid, and resist the operation of time much longer than another kind, which, he says, "is farinaceous, the particles separating as they force their way out, just like meal." meal coming from under the grindstones. A stream of lava of this sort (he justly observes), being less compact, and containing more earthy particles, would certainly be much sooner fit for vegetation than one composed of the more perfect vitrified matter." He has not, however, ventured to determine whether these lavas found below ground were of the former or latter quality; a circumstance which materially affects the justness of his calculation.

That soil gradually increases by decayed vegetables, and the sediment deposited by snow and rain, is an undeniable fact. The thickness or thinness of soil indicates a greater or less time of accumulation. But Sir William has not informed us of the dimensions of his subterraneous vegetable strata; a circumstance of great moment in instituting a calculation of their different eras.

Besides, eruptions of volcanoes are often accompanied with incredible quantities of ashes, which fall thick upon all the ground for many miles round; intended by nature, it would appear, quickly to repair the barrenness occasioned by the lava. The muddy water sometimes thrown out may co-operate powerfully with the ashes in producing the same happy effect.

But Sir William has furnished us with facts of a more important nature. The town of Herculaneum was destroyed by an eruption in the 97th year of the Christian era. There are evident marks, says he, that the matter of six eruptions has taken its course over Herculaneum; for each of the six strata of lava is covered with a vein of good soil. Here we have Sir William's own authority for six strata of good soil, accumulated in less than 1700 years; which, supposing them to be all of equal thickness, instead of 1000 years, leaves not 300 to the production of each.

From the same authority we learn, that the crater on the top of the Monte Nuovo, or New Mountain, which was thrown up by subterraneous fire no farther back than the year 1538, is now covered with shrubs.

There is not on record any eruption from the great crater of Vesuvius from the year 1139 to 1631, a period of only 492 years. But Bracini, who descended into it not long before the 1631, tells us, "that the crater was five miles in circumference, and about 1000 paces deep. Its sides were covered with brushwood, and at the bottom there was a plain on which cattle grazed. In the woody parts, boars frequently harboured," &c.

The correspondence of these facts, related by Sir William himself, with his favourite notion that 1000 years are necessary for the production of a vegetable soil, we leave to the reader's consideration; and shall conclude with a few remarks of a different kind.

The appearance of a stratum of lava below ground, though not covered with vegetable soil, our author considers as demonstrative evidence, that such stratum formerly lay above the surface, and was thrown out by an eruption. This inference, however, seems not altogether just. Nothing, with propriety, receives the denomination of an eruption, unless when lava or other matter is vomited from the crater, or from some new opening made in the mountain. But it deserves notice, that, in the environs of volcanoes, earthquakes are frequent. That these violent concussions are the genuine produce of subterraneous fire expanding itself in every direction, and making strong efforts against every substance which resists the natural tendency of its course, is a fact that cannot admit of doubt. It is no less certain, that these frequent concussions shake and dislocate the internal parts of the earth. They cannot fail to shatter and disarrange the natural direction of the original strata; and, of course, they must give rise to many subterraneous cavities and fissures. The nearer the great furnace, which confines the fury of the flames, the greater and more frequent will be the cavities. Every earthquake occasioned by a volcano is nothing else than an effort of the burning matter to enlarge the boundaries by which it is usually limited. If the quantity of matter and degree of inflammation require a space greatly superior to the internal cavities, an eruption above the surface is an infallible consequence: but when the quantity of matter, or the expansive force occasioned by the degree of inflammation, is insufficient to raise the lava to the top of the mountain, an earthquake may be produced; and the lava, without ever appearing above the surface, may run below ground in plentiful streams, and fill up all the subterraneous cavities and channels. These internal strata of lava may often lie so deep as to be below the level of the sea. In this manner, we conceive it to be not only possible, but extremely probable, that beds of lava, having no covering of vegetable soil, may be found at great depths, although they never were above the surface.

It is much more reasonable to conclude, that lavas with a layer of soil were produced by eruptions, and once lay above the surface, till covered by the operation of time, or subsequent streams from the mouth of the volcano. But even in this case, the argument is not altogether complete; for, as above remarked, earthquakes, with which countries adjacent to volcanoes are perpetually infested, often sink large tracts of land to great depths.

The other parts of the theory of the earth regard the situation of the different parts of its surface with respect to each other; its annual motion round the sun as a planet; its diurnal motion round its axis; and the different strata whereof it is composed, as far as it hath been hitherto found practicable to penetrate into it; for all which, see the articles Geography, Astronomy, Mines, Strata, &c.

Smell and Bath of the Earth. See Agriculture, no. 10.

Bread made of Earth. See Bread.

Earth-Flax. See Amianthus.

Earth-Nuts, or Ground-Nuts, the roots of the Arachis hypogea of Linnæus. They are composed of several small round bulbs or knobs; whence they were termed by Dodonæus, terre glandes or earth-nuts. They are esteemed an excellent food by the Siberians. In Holland likewise, they are sold in the markets and used for food. The native country of this plant seems to be Africa; though, at present, all the American settlements abound with it; but many persons who have resided in that country affirm that they were originally brought by the slaves from Africa. The plant multiplies very fast in a warm country; but being very impatient of cold, it cannot be propagated in the open Earthquake. What countries are most subject to earthquakes.

Earth in Britain. The trees must therefore be planted in a hot-bed in the spring of the year; and when the weather proves warm, they may be exposed to the open air by degrees. The branches of the plant trail upon the ground; and the flowers, which are yellow, are produced single upon long footstalks; and as soon as the flower begins to decay, the germen is thrust underground, where the pod is formed and ripened; so that unless the ground is opened, they never appear: the roots are annual, but the nuts or seeds sufficiently stock the ground in a warm country where they are not carefully taken up.

Earth-Nuts, or Pig-Nuts. See Bunium.

Earth-Puceron, in natural history, a name given by authors to a species of puceron very singular in its place of abode. In the month of March, if the turf be raised in several places in any dry pasture, there will be found, under some parts of it, clutters of ants; and, on a farther search, it will be usually found, that these animals are gathered about some pucerons of a peculiar species. These are large, and of a greyish colour, and are usually found in the midst of the clutters of ants.

The common abode of the several other species of pucerons is on the young branches or leaves of trees; as their only food is the sap or juice of vegetables, probably these earth kinds draw out those juices from the roots of the grasses, and other plants, in the same manner that the others do from the other parts. The ants that conduct us to these, are also our guides where to find the greater part of the others: the reason of which is, that as these creatures feed on the saccharine juices of plants, they are evacuated from their bodies in a liquid form, very little altered from their original state; and the ants, who love such food, find it ready prepared for them in the excrements which these little animals are continually voiding*. It has been supposed by some, that these were the common pucerons of other kinds, which had crept into the earth to preserve themselves from the rigour of the winter. But this does not appear to be the case; for they are usually met with in places very distant from trees or plants, on which they should be supposed before to have fed; and it is very certain, that though many of these insects are killed by the cold, yet many escape, and are found very early in the spring, sucking the buds of the peach-tree. There is no doubt of these creatures being in a feeding condition when under ground; because otherwise the ants would have no temptation to follow them: and it is equally certain, that the several species of the pucerons, like those of the caterpillar kinds, have each their peculiar herbs on which they feed, as many of them will die of hunger rather than feed on any others; and it is not at all likely, that these earth pucerons had been used to feed on leaves of trees and plants, and had left that food for the roots of grass.

Earth-Worms. See Lumbricus.