Page:The Mathematical Principles of Natural Philosophy - 1729 - Volume 1.djvu/386

298 particles of any body whatever RSTV, is the ame as if the body, without removing its centre of gravity, were to put on the form of a globe. Q. E. D.

Hence the motion of the attracted body Z will be the ame, as if the attracting body RSTV were phærical; and therefore if that attracting body be either at ret, or proceed uniformly in a right line; the body attracted will move in an ellipis having its centre in the centre of gravity of the attracting body.

If there be everal bodies coniting of equal particles whoe forces are as the ditance of the places from each; the force compounded of all the forces by which any corpucle is attracted, will tend to the common centre of gravity of the attracting bodies; and will be the ame as if thoe attracting bodies, preerving their common centre of gravity, hould unite there, and be formed into a globe.

This is demontrated after the ame manner as the foregoing propoition.

Therefore the motion of the attracted body will be the ame as if the attracting bodies, preferring their common centre of gravity, hould