Imatges de pÓgina

or twelve hundred per minute. Upon recurring to the records of the most remarkable meteors, we find few whose rate of moving falls within the prescribed limits. Out of twelve cases, which we have collected, and they are all that we have met with, only two answer he conditions required. In these cases the estimated velocits were 150, 160, 180, 348, 350, 720, 1000, 1080, 1080, 1200, 1680, 1800* miles in a minute. It is true, that many of these may be very uncertain, but with respect to others there can be little doubt, after making allowance for every probable mistake, that the velocity is two or three times too great to consist with a revolving body. "In regard to the velocity," says Dr. Pringle, speaking of the meteor of 1758, "it seems almost incredible, as we have sufficient data for computing it at the rate of thirty English miles in a second.” Of the velocity of the meteor of 1783, the several estimates, according to Dr. Blagden, as deduced from the observations of different persons in different places, are twenty, twenty one, thirty, and forty miles in a second. Now it is found that the utmost velocity,† which a body can acquire, not merely by revolving round the earth within prescribed limits, but by falling directly from infinite space to within fifty miles of the earth's surface, is only about seven miles in a second. How then are we to explain these velocities and those of a large majority of meteors that have been observed? Let these velocities be reduced one half, and they are equally unaccountable, equally repugnant to the principles of mechanical philosophy.

There is another hypothesis which has lately made its appearance, we believe, since the paper under review was written. This places the origin of these mysterious substances far beyond the moon. In order to understand it, it must be recollected that the four new planets, which have been lately discov ered, form a most remarkable exception to the analogy which pervades the rest of the system. They are not only of a most

These are the same as those before-mentioned, p. 145. note, with the numbers altered to correspond to one minute.

† See Blagden's remarks upon President Claps theory. Phil. Trans. vol. Ixxiv. p. 224 * New Edinburgh Encyclopædia, vol. ii. part ii. p. 302.

diminutive size, but they are all of them situated at nearly the same mean distance from the sun, and have nearly the same periods of revolution. Several of them differ also very materially from the other planets in the form and position of their orbits. To account for these remarkable anomalies, one who is conversant with such subjects will feel himself almost compelled to seek for some particular cause; and one was soon sug gested, which is rendered, it may be thought, in no small degree probable, from the very wonderful manner in which it applies itself to the solution of difficulties of so various and different a character. This is no other, than that these four small bodies originally composed one planet, of the same rank and character with the other large planets, but that they were severed from. each other by some violent convulsion, and made to describe different orbits, variously inclined and modified. The smaller fragments, in conformity to this theory, yielding more to the internal force, would be likely to diverge more from the original path, and become more excentric, and oblique in the figure and position of their orbits, than the remaining larger portions, which would keep nearer to their former course. Now this is à mere description of facts, so far as our observation yet extends. The hypothesis explains the peculiar phenomena of these planets in the most surprising manner. This then being ad

mitted, we are prepared to give a new account of the origin of meteoric stones, better suited to some of their phenomena, and perhaps not less suited to all, than any of the opinions we have been examining. The bursting of this large planet must inevitably be attended with the separation of innumerable small fragments of all sizes, which must be thrown with great vio lence in all manner of directions. Some of these being removed out of the reach of the larger fragments of the planet, after wandering about some time in the celestial spaces, would begin to feel the influence of some neighbouring planet, and after revolving about it some time, and falling within its atmosphere, would at length come to a termination of their long journey upon the surface of the attracting body. And in case Mars happened to be in a remote part of its orbit, our earth would stand a chance to catch a large proportion of the No. 1. Vol. III.


fragments and dust; for the smallest particles must move; they would also be likely to travel in company, and to be lodged somewhere. Independent of all this, there is one curious circumstance connected with this theory, which ought by no means to be forgotten; and that is, the almost exact agreement in specific gravity, of meteoric stones, with the computed specific gravity of the internal parts of the disrupted planet. The mean density of the new planets is estimated to be about 2, that of water being 1; and reasoning from analogy, as well as from known principles, it is concluded that the internal parts of those planets in their original entire state, ought to be about 34; and the fact is, that the density of meteoric stones has been found to be, with remarkable uniformity, very near this gravity.

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There are two or three other opinions on this subject, which we have not noticed; as that of Dr. Wallis, who supposed that meteors might be small solar comets, and that of Dr. Chladni, who considered them as a sort of minor planets,* or rather a new class of bodies, destined, so far as appears, to no purpose, and subjected to no laws. But we have had enough of empty speculation, of induction from facts too few in number, and too uncertain and vague in their character. We would by no means discourage any exertions to arrange and reduce to order the scanty materials which have been thrown together. But our efforts are directed to the wrong point, the labor would be bestowed, we are persuaded, to more purpose in increasing the stock. There is no end to theorizing; but he who collects facts may be assured that he is in the right way, and though his progress may be slow, he is continually approaching the truth, and may rest satisfied in the end, that he has done something. We


It is worthy of remark that the velocity of a considerable number of meteors approaches very near to that of the earth in its orbit. But this fact does not help us to solve the phenomena of such as move in directions nearly perpendicular to the ecliptic. A body moving in a parabola with: the sun in its focus, and having a perihelion distance equal to the mean dis tance of the earth, might have an absolute velocity in passing the earth of about twenty six miles in a second, and a relative velocity of about forty six. This also fails of affording a solution in those cases, where meteors have moved with a velocity of twenty miles in a second in directions approach ing to a coincidence with that of the earth in its orbit.

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have dwelt long upon this subject, not with the expectation of throwing much light upon it--we have presented it under different aspects, with the hope of exciting some interest, and of calling some attention to this branch of natural knowledge. There is no reason to despair, because little has been attempted. And yet one would think that there were many circumstances to invite attention, and promise success. The scene is immediately before us; the phenomena are presented daily, and sometimes addressed to all the senses, while the planets, and fixed stars, and comets affect only one, and that often feebly, and at long intervals; and yet we have learnt a great deal about these, and derived many advantages, as well as satisfaction, from our knowledge; and we are still extending it. We are following a faint beam of light to other systems, we are exhausting science in the invention of instruments, and our vigilance and zeal in the use of them, to catch a glimpse of a feeble nebula, belonging perhaps to another universe; while a meteor, we know not whence, overpowers us by its light, astounds us by its report, and threatens to dash our telescope from our hands. We are in short assiduously cultivating remote and barren regions, while our garden is running to weeds. Do we despair of doing any thing? Let us recollect that the whole science of as tronomy, the boast of the human intellect, was once in a much more dark and confused state, and the opportunities much rarer of gaining new light. How much have resolution, and diligence, and time, and talents, accomplished! Let us recollect that the science of comets, during the brightest period of the Roman commonwealth, was in the same state as that of me. teors is now; nay it was confounded with it. Do we despair of deriving any benefit from the cultivation of this science, even if successful. Of this it is impossible to judge. Who expected three thousand years ago, that the study of the stars had any thing to do with the ebbing and flowing of the sea, and that a close attention to the phenomena of amber would explain thunder and lightning? What is there to exempt meteors from those laws which extend to all the other objects of our knowledge? If they are solid bodies, they must be comprehended within the limits of a science, that is already far advanced.

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Who will say that they are not intended to supply those defects in navigation, and other arts which are so sensibly felt? Who will say that they will not at some future time show to the lost traveller his way, and tell the unskilful mariner his longitude?


Les Martyrs, ou le Triomphe de la Religion Chrétienne. Par François Auguste de Chateaubriand. Edit. 3e. à Paris, 1810.

The Martyrs; or the Triumph of the Christian religion. From the original French of F. A. de Chateaubriand; with notes. 3 vols. 12mo. New York, Whiting & Watson, 1812. THIS work is the production of one of the most distinguished of the French literati of the present day, and has enjoyed a very high, though not an uncontested reputation in France. It is but little known in Great Britain, or in this country. We do not recollect to have seen a review of it in any of the celebrated English journals, and it is but lately that a translation of it into our language has been published. This is the more remarkable as there is generally among us a great eagerness for the literary povelties of France, as well as of England. This taste is however for the most part confined to novels. The valuable works in the English and French languages are interchanged rather slowly. This fact is more observable in France than in England, In conyersing on literary subjects with persons of taste in Paris, even such as boasted some acquaintance with English literature, we never found any body that was acquainted with Scott, or Southey, or Campbell. They all talk to you of Shakspeare, and Pope, and the Spectator. We, to be sure, have heard much of Delille, the first of French poets, and more beloved for the sweetness of his manners and life, than admired for the elegance of his writings; yet even of him, there are but few readers perhaps that are acquainted with his last production, a poem on Conversation, published about a year and a half ago. Next to him probably the most known of the

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