AUTHOR’S PREFACE

THE SECOND EDITION.

In this second edition of the Principia original: "Principiorum"; shorthand for the "Mathematical Principles of Natural Philosophy", many things are corrected in various places, and several things are added. In Section 2 of the first book, the method of finding the forces vires: the physical influences that cause bodies to move or change motion by which bodies can revolve in given orbits is made easier and more extensive. In Section 7 of the second book, the theory of the resistance of fluids Newton studied how air and water slow down moving objects, a field now called fluid dynamics. is investigated more accurately and confirmed by new experiments. In the third book, the theory of the moon theory of the moon: the mathematical calculation of the Moon's path, which is difficult because it is pulled by both the Earth and the Sun and the precession of the equinoxes precession of the equinoxes: the slow change in the orientation of Earth's rotational axis are more fully derived from their own principles, and the theory of comets is confirmed by more numerous and more accurately computed examples of their orbits.

Given at London,
March 28, 1713.