Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 16, 2025
For a needle to thread itself and then rapidly proceed to sew without the help of fingers calls for the discovery of more "hows" than are needed to explain Laplace's "Mecanique celeste." Mass and gravity suffice for the one, but only a Yankee's mind could have created the other. We have now come to a great word "create."
Judged by a modern code the gravest defect of Laplace's great work is rather of a moral than of a mathematical nature. Lagrange and he advanced together in their study of the mechanics of the heavens, at one time perhaps along parallel lines, while at other times they pursued the same problem by almost identical methods.
See contrasts with Laplace's hypothesis of the origin of the planetary system through the successive separation of rings from the periphery of the contracting solar nebula, and the gradual breaking up of those rings and their aggregation into spherical masses or planets.
Some astronomers, indeed, now reject Laplace's hypothesis in toto, preferring to think that even our solar system originated from a spiral nebula. Since the spiral type prevails among the existing nebulæ, we must make any mechanical theory of the development of stars and planetary systems from them accord with the requirements which that form imposes.
It has been possible here only to sketch out the chief personal points in his career, without dwelling much upon the scientific importance of his later life-long labours; but it must suffice to say briefly upon this point that Herschel's work was no mere mechanical star-finding; it was the most profoundly philosophical astronomical work ever performed, except perhaps Newton's and Laplace's.
Laplace's investigation, had it been correct, would have exactly explained the observed facts. It was, however, now shown that his solution was not correct, and that the lunar acceleration, when strictly calculated as a consequence of solar perturbations, only produced about half the effect which was wanted to explain the ancient eclipses completely.
At the period where the question is taken up in Laplace's treatment of the nebular theory, the shape of this mass is regarded as spheroidal; but at an earlier period its shape may well have been as irregular as that of any of the nebulae which we now see in distant parts of the heavens, for, whatever its primitive shape, the equalization of its rotation would in time make it spheroidal.
Laplace's equations of motion did not express all the relations involved, nor was it possible to judge, from the results he deduced, how far the stability of the Saturnian rings depended on the real structure of these appendages.
Bowditch's notes has little idea of the difficulties to be met in the original work. Even Dr. Bowditch himself said, "I never come across one of Laplace's 'Thus it plainly appears, without feeling sure that I have got hours of hard study before me, to fill up the chasm and show how it plainly appears."
I read with much interest Laplace's report to the Senate, and must confess I was very glad to see the Gregorian calendar again acknowledged by law, as it had already been acknowledged in fact. Frenchmen in foreign countries experienced particular inconvenience from the adoption of a system different from all the rest of the world.
Word Of The Day
Others Looking