[ 435 ] 
Corollary IV. 
Therefore, even allowing the Cartejians^ what one 
has a Right (Corol. I. Theor. IV.) to refufe them, 
they will never be able to explain Keplers Rules in 
the Vortex h for it is only by the Proportion, which I 
have juft now annulled, that they pretend to do it. 
See M. de Molieress Lemons de ‘PhjJique. 
And if it be objeded, that I have not, in the pre- 
ceding Corollaries, had any regard to the Thicknefs 
of the Circumferences ; 1 anfwer, that it was by way 
of pure Conceftion that I have not done it; and if 
anyPerfon will be at the Pains of doing it, he will 
eaftly find, that Kaplers Rules will only be the more 
difturbed thereby. 
CONCLUSION. 
Therefore the Vortex is every way irapoffible, and 
infufiicient in Natural Philofophy. Its mechanical 
Generation is impoflible (Part L); it has only an 
axifugal Force, and not a centrifugal and centripetal 
Force, as it Ihould have (Theor. I. and II.) ; and 
even if it had, it cannot (Theor. III.) defend itfelf 
equally on all Sides. It is not fufficient for explaining 
Gravity, and its Properties ; it deftroys Keplers Aftro- 
nomical Laws (Corol, HI. Theor. IV. and V.). 
What more can be defired, in order to conclude with 
Sir Ifaac Newton? “ Itaque hypothefis Vorticum 
‘‘ (eft impoflibile &) cum phaenomenis aftrooomicis 
“ omnino pugnat, & non tarn ad explicandos quam 
“ adperturbandosmotus coeleftesconducit.” 
K k k 
VII. An 
