Dissertatio II. De impenetrabilitate. On impenetrability; inertia; second and third Newtonian law; central forces; cause of speed; universal gravity of bodies; laws of gravity; for a better understanding of Newtonian theory; phenomena of tides; Galileo's opinion refuted; Descarte's opinion refuted; Kepler's view refuted; Newton's theory approved; nature of comets. 350 pages, 8 folding diagrams.circa 1550-1848ita