SEQUEL TO THE EPOCH OF NEWTON. 431 



Thus the Newtonian system was not adopted in France till the 

 Cartesian generation had died off; Fontenelle, who was secretary to 

 the Academy of Sciences, and who lived till 1*756, died a Cartesian. 

 There were exceptions ; for instance, Delisle, an astronomer who was 

 selected by Peter the Great of Russia, to found the Academy of St. 

 Petersburg ; who visited England in 1724, and to whom Newton then 

 gave his picture, and Halley his Tables. But in general, during the 

 interval, that country and this had a national difference of creed on 

 physical subjects. Voltaire, who visited England in 1727, notices this 

 difference in his lively manner. "A Frenchman who arrives in 

 London, finds a great alteration in philosophy, as in other things. He 

 left the world full [a plenum], he finds it empty. At Paris you see 

 the universe composed of vortices of subtle matter, in London we 

 see nothing of the kind. With you it is the pressure of the moon 

 which causes the tides of the sea, in England it is the sea which grav- 

 itates towards the moon ; so that when you think the moon ought to 

 onve us high water, these gentlemen believe that you ought to have low 

 water ; which unfortunately we cannot test by experience ; for in order 

 to do that, we should have examined the Moon and the Tides at the 

 moment of the creation. You will observe also that the sun, which 

 in France has nothing to do with the business, here comes in for a 

 quarter of it. Among you Cartesians, all is done by an impulsion 

 which one does not well understand ; with the Newtonians, it is done 

 by an attraction of which we know the cause no better. At Paris you 

 fancy the earth shaped like a melon, at London it is flattened on the 

 two sides." 



It was Voltaire himself, as we have said, who was mainly instru- 

 mental in giving the Newtonian doctrines currency in France. He 

 was at first refused permission to print his Elements of the Newtonian 

 Philosophy, by the Chancellor, D'Aguesseaux, who was a Cartesian ; 

 but after the appearance of this work in 1738, and of other writings 

 by him on the same subject, the Cartesian edifice, already without real 

 support or consistency, crumbled to pieces and disappeared. The first 

 Memoir in the Transactions of the French Academy in which the 

 doctrine of central force is applied to the solar system, is one by the 

 Chevalier de Louville in 1720, On the Construction and Theory of 

 Tables of the Sun. In this, however, the mode of explaining the 

 motions of the planets by means cf an original impulse and an attrac- 

 tive force is attributed to Kepler, not to Newton. The first Memoir 

 which refers to the universal gravitation of matter is by Maupertuis, in 



