PROPOS . V. PROBL. In axe extenfo data Parabola punctumfublime reperire, ex quo cadens Parabolam ipfam defcribit. Sit Parabola ab. cujus amplitudo h b, & axis extenfus be. in quo reperienda fit fublimitas , ex qua Cadens, & impetum in aconceptum in horizontalem convertens, Parabolam a b defcribat . Ducatur horizontalis ag. quæ erit parallela ipfi bh. & pofita af, æquali ah, ducatur recta fb. quæ Parabo- lamtangetin b, & horizontalem ag in gfecabit. accipiatur- que ipfarum fag, tertia proportionalis de.Dico e effe pun- &tum fublime quæfitum , ex quo Cadens ex quiète in ; & conceptum impetum in a in horizontale convertens fuper- veniente impetu defcenfus in h ex quiete in a, Parabolam a b defcribet. Si enim intelligamus , ea effe menfuram tempo-
