division of the circle, where the number 600, as mentioned above, might be conveniently substituted for 400. It would not be necessary to adopt their names, which might not assort very well with the sounds that compose the languages of other nations. But the mètre, by whatever name it may be called, ought to be adopted as the unit of length, and all the other measures of linear extension derived from it by decimal multiplication and division. It is true that this cannot be done, especially in our own case, without a certain sacrifice of national vanity; and the times do not give much encouragement to hope that such a sacrifice will be made. The calamities which the power and ambition of the French government have brought on Europe, induce us to look with jealousy and suspicion on their most innocent and laudable exertions. We ought not, however, to yield to such prejudices, where good sense and argument are so obviously against them. In a matter that concerns the arts and sciences only, the maxim may be safely admitted, Fas est et ab hoste doceri. FINIS. REVIEW OF LAPLACE, MECANIQUE CELESTE. * ASTRONOMY is distinguished by several great and striking characters, which place it decidedly at the head of the physical sciences. The objects which it treats of cannot fail to impart to it a degree of their own magnificence and splendour; while their distance, their magnitude, the steadiness and regularity of their movements, deeply impress the imagination, and afford a noble exercise to the understanding. Add to this, that the history of astronomy is that which is best marked out in the progress of human knowledge. Through the darkness of the early ages, we perceive the truths of this science shining as it were by their own light, and scattering some rays around them, that serve to discover a few definite objects amid the confusion of ancient tradition,-a few fixed points amid the uncertainty of Greek, Egyptian, or even Hindoo * From the Edinburgh Review, Vol. XI. (1808.)-Ed. mythology. But what distinguishes astronomy the most, is the perfect explanation which it gives of the celestial phenomena. This explanation is so complete, that there is not any fact concerning the motions of the heavenly bodies, from the greatest to the least, which is not reducible to one single law-the mutual gravitation of all bodies to one another, with forces that are directly as the masses of the bodies, and inversely as the squares of their distances. On this principle Sir Isaac Newton long ago accounted for all the great motions in our system; and, on the same principle, his successors, after near a century of the most ingenious and elaborate investigation, have explained all the rest. The work before us brings those explanations into one view, and deduces them from the first principles of mechanics. It is not willingly that we have suffered so much time to elapse without laying before our readers an analysis of a work the most important, without doubt, that has distinguished the conclusion of the last or the commencement of the present century. But the book is still, in some respects, incomplete; and a historical volume is yet wanting, which, had we been in possession of it, would have very much facilitated the task that we have now undertaken to perform. We know not whether this volume is actually published. In the present state of Europe it may be a long time before it can find its way to this country; and, in the |