PAGE ART. 1. GRAVITATION 1 " 2. CAUSE OF GRAVITATION 1 " 3. NEWTON'S RULES OF PHILOSOPHY 3 " 4. FIRST RULE OF PHILOSOPHY 3 " 5. SECOND RULE OF PHILOSOPHY 4 " 6. THIRD RULE OF PHILOSOPHY 7 " 7. APPLICATION OF RULES TO GRAVITATION 9 " 8. ANALYSIS OF LAW OF GRAVITATION 9 " 9. PRIMITIVE IMPULSE 10 " 10. CENTRIPETAL FORCE 12 " 11. CENTRIFUGAL FORCE 13 " 12. NEWTON'S LAWS OF MOTION 15 " 13. FORCE 16 " 14. FIRST LAW OF MOTION 16 " 15. SECOND LAW OF MOTION 19 " 16. THIRD LAW OF MOTION 20 " 17. SUMMARY OF CHAPTER 22 CHAPTER II PHILOSOPHY OF GRAVITATION--(_continued_) ART. 18. GRAVITATION ATTRACTION 24 " 19. UNIVERSALITY OF GRAVITATION 24 " 20. DIRECTION OF THE FORCES 26 " 21. PROPORTION OF THE FORCES 26 " 22. LAW OF INVERSE SQUARES 27 " 23. TERRESTRIAL GRAVITY 29 " 24. CENTRIFUGAL FORCE 30 " 25. KEPLER'S LAWS 32 " 26. FIRST LAW OF KEPLER 33 " 27. SECOND LAW OF KEPLER 36 " 28. THIRD LAW OF KEPLER 37 CHAPTER III MATTER