17. Of Figures Deficient 246 18. Of the Equation of Strait Lines with the Crooked 268 Lines of Parabolas, and other Figures made in imitation of Parabolas 19. Of Angles of Incidence and Reflection, equal by 273 Supposition 20. Of the Dimension of a Circle, and the Division of 287 Angles or Arches 21. Of Circular Motion 317 22. Of other Variety of Motions 333 23. Of the Centre of Equiponderation of Bodies 350 pressing downwards in Strait Parallel Lines 24. Of Refraction and Reflection 374 PART FOURTH, OF PHYSICS, OR THE PHENOMENA OF NATURE. 25. Of Sense and Animal Motion 387 26. Of the World and of the Stars 410 27. Of Light, Heat, and of Colours 445 28. Of Cold, Wind, Hard, Ice, Restitution of Bodies 466 bent, Diaphanous, Lightning and Thunder, and of the Heads of Rivers 29. Of Sound, Odour, Savour, and Touch 485 30. Of Gravity 508 ------------------------------------------------------------------------ COMPUTATION OR LOGIC. ------- CHAPTER I. OF PHILOSOPHY. 1. The Introduction.—2. The Definition of Philosophy explained.—3. Ratiocination of the Mind.—4. Properties, what they are.—5. How Properties are known by Generation, and contrarily.—6. The Scope of Philosophy.—7. The Utility of it.—8. The Subject.—9. The Parts of it.—10. The Epilogue. [Sidenote: Introduction.]