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After this newborn point of earth had gained some degree of elevation, it is proba ble that successive coats of vegetation, according to Dr. Darwin's idea, springing up, then falling and dying on the earth, paid an annual tribute to the infant continent, while

a bouleversemente of a whole continent, rather than to depend on so slow and imperceptible an operation as that of alluvion. This is not philosophical. Neither on the other hand would it be philosophical to reject a theory because it might be new and unsupported by a name. On the contrary, the man who on any branch of philosophy starts a new hypothesis, which has even the guise of reason, confers a benefit on the world; for he enlarges the ground of thought, and although not immediately in the temple of truth himself, may have dropped a hint, an accidental clew, which may serve to lead others to the door of the temple. In this spirit, I not only excuse, but am grateful even for, the wildest of Dr. Darwin's philosophical chimeras. In the same spirit, I offer, without the expectation of its final adoption, the idea suggested by this note as to the cause of a western current.

each rain, which fell upon it, bore down a part of its substance and assisted perpetually in the enlargement of its area.

It is curious that the arrangement of the mountains both in North and South America, as well as the shape of the two continents, combine to strengthen the preceding theory. For the mountains, as you will perceive on inspecting your maps, run in chains from north to south; thus opposing the widest possible barrier to the sands, as they roll from east to west. The shape of the continent is just that which would naturally be expected from such an origin: that is, they lie along, collaterally, with the mountains. As far north as the country is well known, these ranges of mountains are observed; and it is remarkable, that as soon as the Cordilleras terminate in the south, the continent of South America ends: where they terminate in the north, the continent dwindles to a narrow Isthmus.

Assuming this theory as correct, it is amusing to observe the conclusions to which it will lead us.

As the country is supposed to have been formed by gradual accumulations, and as these accumulations, were most probably equal or nearly so in every part, it follows that, broken as this country is in hills and dales, it has assumed no new appearance by its emersion; but that the figure of the earth's surface is the same throughout, as well where it is now covered by the waters of the ocean as where it has been already denudated. So that Mr. Boyle's mountains in the sea cease to have any thing wonderful in them.

Connected with this, it is not an improbable conclusion, that new continents and islands are now forming on the bed of the ocean. Perhaps, at some future day, lands may emerge in the neighbourhood of the Antarctic circle, which by progressive accumulations and a

consequent increase of weight, may keep a juster balance between the poles, and produce a material difference in our astronomical relations. The navigators of that day will be as successful in their discoveries in the southern seas, as Columbus was heretofore in the northern. For there can be little doubt that there has been a time when Columbus, if he had lived, would have found his reasonings, on the balance of the earth, fallacious; and would have sought these seas for a continent, as much in vain, as Drake, Anson, Cook and others, encouraged perhaps by similar reasoning, have since sought the ocean of the south.

If Mr. Buffon's notion be correct, that the eastern coast of one continent is perpetually feeding on the western coast of that which lies before it, the conclusion is inevitable, that the present materials of Europe and Africa, and Asia in succession, will at some future day

compose the continents of North and South America; while the latter, thrown on the Asiatic shore, will again make a part, and, in time, the whole of that continent, to which by some philosophers, they are supposed to have been originally attached. It is equally clear that, by this means, the continents will not only exchange their materials, but their position; so that, in process of time, they must respectively make a tour around the globe, maintaining, still, the same ceremonious distance from each other, which they now hold.

According to my theory, which supposes an alluvion on the western as well as the eastern coast, the continents and islands of the earth, will be caused, reciprocally, to approximate, and (if materials enough can be found in the bed of the ocean, or generated by any process of nature) ultimately to unite. Our island of Great Britain, therefore, at some

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