120 DISSERTATION SECOND. [pabtii, 



vance very slowly indeed among foreign nations. In 

 France, we find the first astronomers and mathematicians, 

 such men as Cassini and Maraldi, quite unacquainted with 

 it, and employed in calculating the paths of the comets they 

 were observing, on hypotheses the most unfounded and 

 imaginary; long after Halley, following the principles of 

 Newton, had computed tables from which the motions of all 

 the comets that ever had appeared, or ever could appear, 

 might be easily deduced. Fontenelle with great talents 

 and enlarged views, and, as one may say, officially in- 

 formed of the progress of science all over Europe, con- 

 tinued a Cartesian to the end of his days. Mairan in his 

 youth was a zealous defender of the vortices, though he 

 became afterwards one of the most strenuous supporters 

 of the doctrine of gravitation. 



A Memoir of the Chevalier Louville, among those of 

 the Academy of Sciences for 1720, is the first in that col- 

 lection, and, I believe, the first published in France, where 

 the elliptic motion of the planets is supposed to be pro- 

 duced by the combination of two forces, one projectile and 

 the other centripetal. Maupertuis soon after went much 

 farther; in his elegant and philosophic treatise, Figure des 

 Jlstres, published about 1730, he not only admitted the ex- 

 istence of attraction as a fact, but even defended it, when 

 considered as an universal property of body, against the 

 reproach of being a metaphysical absurdity. These were 

 considerable advances, but they were made slowly ; and it 

 was true, as Voltaire afterwards remarked, that though the 

 author of the Principia survived the publication of that 

 great work nearly forty years, he had not, at the time of 

 his death, twenty followers out of England. 



We should do wrong, however, to attribute this slow 

 conversation of the philosophic world entirely to prejudice, 

 ihertness, or apathy. The evidence of the Newtonian 



