IN THIS SECOND EDITION of the Principles, many emendations have been made here and there, and some new things have been added. In sec. 2 of book 1, the finding of forces by which bodies could revolve in given orbits has been made easier and has been enlarged. In sec. 7 of book 2, the theory of the resistance of fluids is investigated more accurately and confirmed by new experiments. In book 3 the theory of the moon and the precession of the equinoxes are deduced more fully from their principles; and the theory of comets is confirmed by more examples of their orbits, calculated with greater accuracy.
Is. Newton
London
28 March 1713