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able to many objections, which, to me at least are insuperable....I will briefly notice some of the: most obvious.

Although alluvion may account for small accessions of soil nearly on a level with the ocean, it cannot explain the formation of mountains. It is contrary to all the known laws of nature to suppose that a fluid could lift, so far above its own level, bodies many times heavier than itself. Again, if the ocean, as Buson maintains, has a tendency to wear away all points and eminences over which it passes, it would exert this tendency on the mountains itself had formed, or rather,. it would prevent their formation. It is surely inconsistent to suppose the ocean would produce mountains, and at the same time wear away those that already existed. Indeed, the author himself seemed to be aware of the invincible objections to this part of his theory, and endeavors to evade their force by sinking a part of the earth, in the cavity occasioned by which, the superfluous waters find a sufficient receptable; thus abandoning the agency of alluvion, and adopting a new and totally different hypothesis.

But while marine substances are found far a bove their proper element, vegetable bodies are often found far below the seat of their production. In Europe they often meet with wood, at great depths of the earth, in a state of perfect preservation, and in sinking wells, in this country, trunks of trees frequently obstruct the progress of the work. A Mr. Peters of Harrison county not long since met with pieces of pine, twenty feet below the surface, on a hill of considerable eleva

tion, and at a distance from any water course..... In this town, leaves, believed to be those of the hazle, were found mingled with marine productions. These vegetable matters must have been once exposed to air, heat and light, to have attained the state in which they were found, and the same exposure would have afterwards caused their decay, unless their interment had been sudden and complete. Bones, shells and other extraneous substances, are often found bedded in marble and other hard bodies, and I myself have seen a specimen of those human bones, which in the fortifications of Gibraltar are often found incorporated with the solid rock..... What less than some great throe of nature, or some mighty agent, now dormant and unknown, could have produced the general bouleversement which these appearances indicate ?

But the hypothetical reasoning of Monsieur de Buffon, is founded on a fact no less hypothetical. The arguments in favor of a general current to the west, are I confess, very cogent, and would be convincing but for the following difficulties.

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1. If the operation of the sun and moon, in ducing alternate elevations and depressions of the ocean, produce also a current, the force of this current will be in proportion to the mass of water thus raised and depressed. Now, contrary to the assertion of Buffon, the tides are highest in high latitudes, and gradually diminish towards the equator, where I believe they hardly exceed a foot. By the observations of Captain Cook, the same difference exists in the Pacific Ocean as was long known in the Atlantic. If then, there

is a general current to the west, it should be strongest in high latitudes and weakest under the line. But the contrary is the fact. No general current to the west is found without the tropics, and that which prevails irregularly between them, is usually and rationally ascribed to the trade winds.

2. If this supposed current existed, its effect would be readily perceived by our navigators in the difference of their passages to and from Europe, but, the one before referred to, excepted, they meet with nothing of the kind. A current at the rate of one mile an hour, would make a difference of near two thousand miles between an ordinary voyage to and from Europe.

3. By actual observations detailed in the 2d vol. of the Philosophical Transactions, the prevailing currents about some islands in the Atlantic Ocean are to the east. At Owhyhee, which lies within the,tropics, and nearly in the middle of the Pacific Ocean, Capt. Cook observed the current to set, without any regularity, sometimes to the west, and sometimes to the east.

4. But one argument may be deemed conclu-. sive. The air is a fluid at least as sensible to the gravitating power of the planets as the Ocean, and, like that, must also have its tides. If, on the one hand, the tides of the air are more liable · to be disturbed by its compressibility, by partial rarefaction or condensation, its obstacles, on the other hand, to a free motion round the earth, are comparatively inconsiderable. Its course is somewhat impeded, but never arrested. If then such a general law existed, as is contended for D

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there would be, either a steady east wind, or greater flow of air from that quarter than from the west, in every climate of the globe. But this is the case only between the tropics, and the valence of the east wind in that region, has been almost universally ascribed to rarefaction by heat, since no other solution can account for the sea and land breezes, monsoons, and other phenomena of those climates.

From these considerations I am disposed to think, that there is no uniform current to the west, or that it is too inconsiderable to have any effect on the figure of the earth. Admitting the existence of a general current, it may be merely superficial. Currents whose force gradually diminishes from the surface downwards, are known to exist, and the practice of seamen, when they wish" to try the current," is evidently founded on the belief that they do not extend to great depths. The accession of water by the tides is too small to require a general movement of the ocean to its bottom.

In weighing the probability of a general current to the west, I have confined myself to the operation of the tides, as the mere motion of the earth, either in its orbit, or on its axis, can have no possible effect this way. This motion is communicated to every part of the earth, whether solid or fluid, and while it continues equable, they are both affected alike, and their relative situations remain the same. So well established a principle must have been contested by the British Spy through mere inadvertence.

If, after all that has been said, arguments in

favor of a current from the surface to the bottom, be deemed conclusive, it is worth while to enquire into its probable effects.

The British Spy supposes that this general current enlarges both the eastern and western coasts of continents; in which hypothesis, he differs less from Buffon than that elegant but fanciful theorist differs from himself. For, in his theory on the formation of the planets, he advances that the ocean is continually wearing away the eastern coasts, and by a process which he does not even hint at, enlarging the western; and that Asia is an older country than Europe. But in a subse

quent work, his Epochs, he maintains the direct reverse, and mentions the abruptness of the western, and the greater number of islands of the eastern coasts, as evidences that the former have been abraded by the ocean.

But I find neither reasoning nor fact to warrant either of these conclusions. It has been ob served that a shore forms a convex outline where it gains on the ocean, and a concave where it loses. On inspecting the map of the world, we perceive nothing, which by this standard, indicates a greater increase on one continent than on the other, or even any increase at all. We see no vast prominence of coast under the line, but. on taking both shores of the ocean, in both hemispheres, into comparison, we find that the convexities on the western side are balanced by equal convexities on the eastern. Besides, it is clear that in proportion as the contents of the ocean are cast on the land, in the same degree it be comes deeper, and its shores more steep and ab

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