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NORTH AMERICAN REVIEW.
NEW SERIES, NO. XXV.
Art. I.— Transactions of the American Philosophical Soci
ety, for promoting useful Knowledge. Vol. II. New Se
ries. A. Small. Philadelphia. 4to. pp. 503. The American Philosophical Society was instituted at Philadelphia, about eighty years ago, chiefly through the instrumentality of Dr Franklin. The elevated genius and ardent love of knowledge, which were among the rare traits of this, great philosopher and statesman, impelled bim by all practicable means not only to discover, but to communicate truth, not only to develope the principles of nature and the laws of social intercourse, but to make his acquisitions useful to the greatest possible extent. Franklin was truly the friend of his species, and believed no labor without its reward, which taught men the art of understanding and improving their condition, or, in other words, the art of securing their independence, prosperity, and happiness, by their own exertions. All his researches in physical science, politics, morals, and the economy of life, aim at utility; he employed philosophy as an instrument of good to mankind, and converted knowledge to its proper ends. In these intellectual habits of Franklin originated the Philosophical Society at Philadelphia.
For several years the Society was little more, than an association of scientific gentlemen, for the purpose of aiding one another in their pursuits by conversation and concert. The meetings of the Society were also frequently interrupted VOL. XXII.-N0. 50.
during the revolutionary war. But the activity of its members did not cease, and their labors have been recorded in successive volumes of Transactions. In the present article our attention is drawn to the volume last published, being the eighth from the beginning, and the second of the new series. The Society ranks among its numbers some of the most distinguished men of letters and science in this country and in Europe, and many of the contributions to its Transactions are from high sources. The meetings are held in a handsome and commodious building in Philadelphia, which belongs to the Society, and which contains a library of about six thousand volumes, and various specimens of natural history. The catalogue of this library, formed under the immediate direction of Mr Duponceau, is one of the best, in the methodical and philosophical principles of its arrangement, that we have ever seen. The original purpose of the Society was the cultivation of the physical and exact sciences, and to this it was long confined. The plan has recently been enlarged, by embracing history, moral science, and general literature. The standing committee, appointed for this department, published six years ago a separate volume, with encouragement that another would in due time appear. We hope the time will soon arrive. This new department reaches to so wide a compass of interesting inquiry, that it cannot fail to enlist more able minds in the cause of the Society, and thereby increase its dignity and extend its usefulness. The presidents have been successively, Benjamin Franklin, David Rittenhouse, Thomas Jefferson, Caspar Wistar, Robert Patterson, and William Tilghman, the present distinguished Chief Justice of the Commonwealth of Pennsylvania.
This Society, not more on account of its antiquity and the high character of its members, than of its objects and its past labors, justly claims the respect of all lovers of science, and friends of improvement in this country. Amidst the numerous societies, which are almost daily shooting up around us, with pompous titles and long lists of officers, with constitutions, and bylaws, and boasts of great projects in hand, but which sink away and go out of sight, after a little vain bustling on the part of a few zealous candidates for the offices at the next election, when their names may appear at full length as part of the news of the day, or perhaps at the bottom of a report detailing with great formality, what the society intends to do; we say, in the midst of all this empty parade and pretence, it is with sincere pleasure that we can look up to the Philosophical Society, and the Academy of Natural Sciences, in Philadelphia, as institutions creditable to themselves and the country, by the dignity of their objects, and by the steady and substantial efforts with which these objects are prosecuted. A very few others may be entitled to a similar preference, but the number is exceedingly small. We could wish, indeed, that our own American Academy, whose doings have been so laudable in years gone by, would more frequently give other tokens of its existence, than the annual list of new members published in the newspapers.
We do not object to literary and scientific associations; on the contrary, we believe they may be made the means of vast improvement to individuals and to the community ; but we confess that we have no patience with the growing fashion of building up these associations, and enlarging them, merely for a noise and a puff, as a convenient mode by which a number of persons may keep each other in countenance in making pretensions, which, singly, they would never dare to make, and which, under no circumstances, can they ever realise. The whole business is arrant quackery, and although it breaks no bones, nor administers any poison, yet it deceives the public, and as far as any effect is produced, it is to bring literature and science into disrepute.
The present volume of Transactions contains several important papers, some of which are so purely scientific, that we should fail in any attempt to analyse them, were such an analysis within the scope of our journal. Three or four may be selected, however, on which we trust a few observations will not be unacceptable to our general readers. The paper by Dr Drake, containing a Geological Account of the Valley of the Ohio, is curious not more for its facts, than for the ingenious speculations of the author, in attempting to account for certain geological phenomena in the western country. His paper is accompanied with a profile of the valley of the Ohio, running transversely across the river at Cincinnati, and indicating the alluvial formations on each bank of the river at that place.
The banks of the Ohio, like those of the Connecticut, and in fact we believe of most of our rivers, are composed of two or three platforms, or distinct plains, rising one above another by elevations varying from ten to fifty feet. These platforms are alluvial, extending from hill to hill across the valley through which the river finds its passage, and have evidently been deposited at some former period by the waters of the river. But it is common for the highest platform, or that bordering on the mountainous or hilly formation, to be sixty, eighty, and even a hundred feet above the highest level to which the river now rises. The necessary result is, that the quantity of water which flowed in the river, when these deposits were made, was such as to fill the whole valley to that elevation, and as the water for some cause became diminished in quantity, it gathered itself into a narrower channel, and left the dry soil on its margin. One of the most singular circumstances attending this diminution of the water, is, that it seems to have been done at certain periods, and thus to have formed the regular succession of ascents and plains mentioned above. Had the subsiding of the water been uniform, the surface of the deposit would now be a gradual slope, from the base of the hills to the margin of the river. As these platforms and ascents are commonly two or three in number, on the borders of the large rivers east and north of the Mississippi, and we suppose of the Rocky Mountains, it is reasonable to refer them all to a cause acting at the same time, and to draw the conclusion, that the northern continent of America has at two or three particular seasons undergone signal revolutions, either by internal convulsions, or by the sinking of a large extent of country now occupied by the Atlantic Ocean, and thus leaving a space to be filled by the waters of the valleys, which have since dwindled into comparatively small streams. There is a difficulty, however, about the whole matter, when we ask how these immense rivers were supplied in former times, since, by the ordinary process of nature in evaporation, rains, and internal circulation, no more water is produced than enough to sustain the rivers in their present diminished channels.
Dr Drake does not puzzle himself, nor his readers, with speculations on these general bearings of the subject, but his investigations are chiefly confined to the valley of the Ohio.
He first inquires into the cause of the great excavation through which this river runs, and gives it as his opinion, that this broad valley, as well as that of the Mississippi, was originally caused by the sinking of a region now covered by the Gulf of Mexico, and thus giving a southerly current to the waters, which before that time overspread the regions at the north. In this way the great valleys were formed by the strong currents and perpetual abrasion of the waters. Another mode of accounting for the same thing would be to suppose, that the elevations and depressions of the surface, or the mountains and valleys, were produced by some violent convulsion within, and that the waters sought a passage in the most depressed parts. From various geological appearances Dr Drake thinks it quite certain, that such could not have been the origin of the great valleys and elevations of the west, although he allows that on the south of the Ohio river, in some parts of Kentucky, there are ravines and abrupt eminences, which indicate the action of some violent cause beneath. In modern times the river has become contracted in widih, and the bed of its channel deepened. This channel is now worn many feet below the bottom of the alluvial deposits on its margin. It is continually increasing in depth, though Dr Drake says very slowly, as the current at the bottom of the river is always much less rapid than at the surface, except at the time of floods or freshets.
This is easily ascertained in the summer season, when the water of the river is clear, and the bottom can be distinctly seen. Accumulations of light particles are found resting there, when the current at the surface is so strong, as instantly to carry away much heavier substances. It follows that the attrition of the water at the bottom is much less, than would be apprehended from its velocity above, and that the process of deepening the channel is extremely slow.
Dr Drake accounts for some remarkable geological appearances in the western country in a manner so curious and plausable, that we shall present his views in his own language. After describing the gravelly substances, or debris, which occur in the regions of the Ohio river, and which are found of a similar composition and character, as he says, all over tlie western and northern parts of the United States, he proceeds as follows.