mento vires, quibus(uperficies convolutione arcaum KL, k/ de-{criptz trahunt corpufcula, erunt, ut ps quad. ad PS quad. 5; in-q; eadem ratione erunt vires fuperficierum omnium circularıumin quas utraq; fuperficies Spherica, capiendo{emper_s d=SD&se=SE, diftingui poteft. Et per Compolfitionem,, vires totä-rum fuperficierum Sphzricarum in corpufcula exercitg erunt ıneadem ratione. Q. E. D.) 0

Prop. LXXII. Theor. XXXI.

Si ad Sphere cujufvis punsta fingula tendant wires xquales centripe-te decrefcentes in duplicata ratione difkantiarum a pungtis, ac de-tur ratio diametri Sphere ad diftantiam corpufculi a centro es 5dico quod wis qua corpufenlum attrahitur proportionalis erit femt-diametro Sphere.;

Nam concipe corpufcula duo{eorfim a. Sphzris duabus attra-hi, 8 diftantias a centris proportionales efle diametris, Spharasautem refolvi in particulas fimiles 8& fimiliter pofitas ad corpuf-cula. Hinc attra&iones corpufculi unius, faCtz verfüs{ingulas par-ticulas Spherz unius, erunt ad attractiones alterius verfus analo-.gas totidem particulas Sphere alterius, in ratione compolfita€xratione particularum diredte& ratione duplicata diftantiarum in-verfe. Sed particule funt ut Sphere, hoc eft in ratione tripli-cata diametrorum,& diftantize{unt ut diametri,& ratio priordire&e una cum ratione pofteriore bis inverfe eft ratio diametriad diametrum. Q. E.D.

Corol. x. Hinc fi corpufcula in circulis circa Spheras ex_mate-ria zqualiter attradiva conftantes revolvantur, fintq; diftantiea centris Spherarum proportionales carundem diametris; tcm-pora periodica erunt xqualia.

* Bb2/ Corol,