that may ſerve exactly to retain a body in a given orbit with a given velocity; and vice verſa, to determine the curvilinear way into which a body projected from a given place, with a given velocity, may be made to deviate from its natural rectilinear way, by means of a given force.
The quantity of any Centripetal Force may be conſidered as of three kinds: Abſolute, Accelerative, and Motive.
Definition VI.
Thus the magnetic force is greater in one load-ſtone and leſs in another, according to their ſizes and ſtrength.
Definition VII.
Thus the force of the ſame load-ſtone is greater at a leſs distance, and leſs at a greater: alſo the force of gravity is greater in valleys, leſs on tops of exceeding high mountains; and yet leſs (as ſhall hereafter be ſhewn) at greater diſtances from the body of the