7. The apparent path of Mercury 17 8-11. The phases of the moon 30, 31 12. The curvature of the earth 32 13. The method of Aristarchus for comparing the distances of the sun and moon 34 14. The equator and the ecliptic 36 15. The equator, the horizon, and the meridian 38 16. The measurement of the earth 39 17. The eccentric 44 18. The position of the sun’s apogee 45 19. The epicycle and the deferent 47 20. The eclipse method of connecting the distances of the sun and moon 50 21. The increase of the longitude of a star 52 22. The movement of the equator 53 23, 24. The precession of the equinoxes 53, 54 25. The earth’s shadow 57 26. The ecliptic and the moon’s path 57 27. The sun and moon 58 28. Partial eclipse of the moon 58 29. Total eclipse of the moon 58 30. Annular eclipse of the sun 59 31. Parallax 60 32. Refraction by the atmosphere 63 33. Parallax 68 34. Jupiter’s epicycle and deferent 70 35. The equant 71 36. The celestial spheres 89 PORTRAIT OF COPPERNICUS _To face p._ 94 37. Relative motion 102 38. The relative motion of the sun and moon 103 39. The daily rotation of the earth 104 40. The solar system according to Coppernicus 107 41, 42. Coppernican explanation of the seasons 108, 109 43. The orbits of Venus and of the earth 113 44. The synodic and sidereal periods of Venus 114 45. The epicycle of Jupiter 116 46. The relative sizes of the orbits of the earth and of a superior planet 117 47. The stationary points of Mercury 119