have laboured rather to support a favourite hypothesis than to consult the voice of authentic history, or patiently to examine the materials and structure of the fabric which they undertook to describe. It may, however, not be improper to take a brief review of some of the more conspicuous among the great number which, at different periods and in different parts of the world, have been received by philosophers.

SECT. II.

THEORY OF BURNET.

THE first theory of geology which deserves to be noticed is that of the Rev. Dr. Thomas Burnet.* This celebrated theorist was a man of genius and taste; and his work, if it do not command the assent of the philosophic mind, will be found to display much learning, and a very vigorous imagination. According to Dr. Burnet the earth was first a fluid heterogeneous mass. The heaviest

parts descended and formed a solid body. The waters took their station round this body, and all lighter fluids rose above the water. Thus, between the coat of air and that of water a coat of oily matter was interposed. But as the air was then full of impurities, and contained great quantities of earthy particles, these gradually subsided and rested upon the stratum of oil, and composed a crust of earth mixed with oleaginous matter. This crust was the first inhabitable part of the earth; and was level and uniform, without mountains, seas, or other inequalities. In this state it remained about sixteen centuries, when the heat of the sun, gradually drying the crust, produced, at first, superficial fissures or cracks; but, in process of time, these fissures became deeper, and increased so much, that at last they entirely penetrated the crust. Immediately the whole split in pieces, and fell into the abyss of waters which it had formerly surrounded. This wonderful event was the universal Deluge. These

* Telluris Theoria Sacra. This work was first published in 1680 in the Latin language. It was afterwards translated by the author, and published in two parts in 1683 and 1690.

masses of indurated earthy matter, in falling into the abyss, carried along with them vast quantities of air, by the force of which they dashed against each other, accumulated, and divided in so irregular a manner, that great cavities, filled with air, were left between them. The waters gradually opened passages into these cavities, and in proportion as the cavities were filled with water, parts of the crust began to discover themselves in the most elevated places. At last the waters appeared no where but in those extensive vallies which contained the ocean. Thus our ocean is a part of the ancient abyss; the rest of it remains in the internal cavities, with which the sea has still a communication. Islands and rocks are the small fragments, and continents the large masses, of the antediluvian crust and as the rupture and fall of the mass were sudden and confused, the present surface of the earth is full of corresponding confusion and irregularity.*

SECT. III.

THEORY OF WOODWARD.

THIS " elegant romance" of Burnet was succeeded by the work of his countryman, Mr. Woodward, who, in 1695, published Essays towards a Natural History of the Earth, and terrestrial bodies.

Though he possessed much more knowledge of minerals than his predecessor, and on this account had greatly the advantage of him, he produced a work far less ingenious and interesting. He also proceeded on the supposition of the Mosaic history being true, and ascribed the present aspect of our globe to the influence of the general deluge. He supposed that all the substances of which the earth is composed were once in a state of solution; that this solution took place at the flood; that on the gradual retiring of the waters the various substances held in solution, or suspended in them, subsided in distinct strata, according to their specific gravities; and that these are arranged horizontally, one over the other, like the coats of an onion. As this theory was soon found

* Sullivan's View of Nature, vol. i. Letter 6. VOL. I.

3

to contradict some of the plainest and most unquestionable facts which geologists observed, it has had few admirers, and its refutation has been usually considered as obvious and easy.

SECT. IV.

THEORY OF WHISTON.

IN 1696 Mr. William Whiston, a man of uncommon acuteness, and of still greater learning, published a New Theory of the Earth, from its original to the consummation of all things. He supposed the earth, in the beginning, to be an uninhabitable Comet, subject to such alternate extremes of heat and cold, that its matter, being sometimes liquefied and sometimes frozen, was in the form of a chaos, or an abyss surrounded with utter darkness. This chaos was the atmosphere of the comet, composed of heterogeneous materials, having its centre occupied with a globular, hot, solid nucleus, of about two thousand leagues diameter. Such was the condition of the earth before the period described by Moses at the time of creation. The first day of the creation every material in this rude mass began to be arranged according to its specific gravity. The heavy fluids sank down, and left to the earthy, watery, and aerial substances, the superior regions. Round the solid nucleus is placed the heavy fluid, which descended first, and formed the great abyss, upon which the earth floats, as a cork upon quicksilver. The great abyss is formed of two concentric circles; the interior being the heavy fluid; and the superior, water; upon which last, the earth, or the crust we inhabit, is immediately formed. So that, according to this theorist, the globe is composed of a number of coats or shells, one within the other, of different materials, and of different densities. The air, the lightest substance of all, surrounds the outer coat; and the rays the sun, making their way through the atmosphere, produced the light which Moses tells us first obeyed the divine command. The hills and vallies are formed by the mass of which they consist pressing with greater or

of

less weight upon the inner coat of the earth; those parts which are heaviest sinking lowest into the subjacent fluid, and making vallies, and those which are lightest rising higher and forming mountains.

Such Mr. Whiston supposed to be the state of the globe we inhabit before the Deluge. Owing to the superior heat, at that time, of the central parts, which have been. ever since cooling, the earth was more fruitful and populous anterior to that event than since. The greater vigour of the genial principle was more friendly to animal and vegetable life. But as all the advantages of plenty and longevity which this circumstance produced were productive only of moral evil, it pleased God to testify his displeasure against sin, by bringing a flood upon a guilty world. The flood was produced, as this theorist supposed, in the following manner. A Comet, descending in the plane of the ecliptic to its perihelion, made a near approach to the earth. The approximation of so large a body raised. such a strong tide, and produced such powerful commotion in the abyss concealed under the external crust, that the latter was broken, and the waters which had been before pent up, burst forth with great violence, and were the principal means of producing the deluge. In aid of this, he had recourse to another supposition, which was, that the comet, while it passed so near the earth as to produce these effects by the force of attraction, also involved our globe in its atmosphere and tail for a considerable time, and deposited vast quantities of vapours on its surface, which produced violent and long-continued rains; and, finally, that this vast body of waters was removed by a mighty wind, which dried up a large portion, and forced the rest into the abyss from which it had been drawn, leaving only enough to form the ocean and rivers which we now behold,

SECT. V.

THEORY OF HUTCHINSON.

AT an early period of the eighteenth century, the celebrated John Hutchinson formed a theory of the earth, which he professed to derive from Scripture.* He supposed, that, when the earth was first created, the terrestrial matter was entirely dissolved in the aqueous, forming a thick, muddy, chaotic mass; that the figure of this mass was spherical, and on the outside of this sphere lay a body of gross dark air; that within the sphere of earth and water was an immense cavity, called by Moses the deep; that this internal cavity was filled with air of a kind similar to that on the outside; that on the creation of light the internal air received elasticity sufficient to force its way through the external covering; that immediately on this, the water descended, filled up the void, and left the earth in a form similar to that which it bears at present; that when it pleased God to destroy mankind by a flood, he caused, by his own miraculous agency, such a pressure of the atmosphere on the surface of the earth, that a large portion of it was forced into the internal cavity which it had formerly occupied, and expelled the waters from it with great violence, spreading them over the surface; that the shell of the earth was by this means utterly dissolved, and reduced to its original state of fluidity; and that, after the divine purposes were answered by the deluge, the globe, by a process similar to that which at first took place, was restored to the form which it now bears.

This theory was enlarged and commented upon by Mr. Catcot, a follower of Hutchinson, who, in 1768, published a volume on the subject.