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Contents
PAGE
| § 167. | Chief divisions of his work : astronomy, optics, pure mathematics |
211 |
| § 168. | Optical discoveries : the reflecting telescopes of Gregory and Newton : the spectrum |
211 |
| § 169. | Newton's description of his discoveries in 1665-6 |
212 |
| § 170. | The beginning of his work on gravitation : the falling apple : previous contributions to the subject by Kepler, Borelli, and Huygens |
213 |
| § 171. | The problem of circular motion : acceleration |
214 |
| § 172. | The law of the inverse square obtained from Kepler's Third Law for the planetary orbits, treated as circles |
215 |
| § 173. | Extension of the earth's gravity as far as the moon : imperfection of the theory |
217 |
| § 174. | Hooke's and Wren's speculations on the planetary motions and on gravity. Newton's second calculation of the motion of the moon : agreement with observation |
221 |
| § 175-6. | Solution of the problem of elliptic motion : Halley's visit to Newton |
221 |
| § 177. | Presentation to the Royal Society of the tract De Motu : publication of the Principia |
222 |
| § 178. | The Principia : its divisions |
223 |
| §§ 179-80. | The Laws of Motion: the First Law: acceleration in its general form : mass and force : the Third Law |
223 |
| § 181. | Law of universal gravitation enunciated |
227 |
| § 182. | The attraction of a sphere |
228 |
| § 183. | The general problem of accounting for the motions of the solar system by means of gravitation and the Laws of Motion: perturbations |
229 |
| § 184. | Newton's lunar theory |
230 |
| § 185. | Measurement of the mass of a planet by means of its attraction of its satellites |
231 |
| § 186. | Motion of the sun : centre of gravity of the solar system : relativity of motion |
231 |
| § 187. | The non-spherical form of the earth, and of Jupiter |
233 |
| § 188. | Explanation of precession |
234 |
| § 189. | The tides : the mass of the moon deduced from tidal observations |
235 |
| § 190. | The motions of comets : parabolic orbits |
237 |
