EONARDO DA VINCI 10

3. COPERNICUS 12

4. HOMERIC COSMOGONY 15

5. EGYPTIAN SYMBOL OF THE UNIVERSE 16

6. HINDOO EARTH 17

7. ORDER OF ANCIENT PLANETS CORRESPONDING TO THE DAYS OF
THE WEEK 19

8. PTOLEMAIC SYSTEM 20

9. SPECIMENS OF APPARENT PATHS OF VENUS AND OF MARS
AMONG THE STARS 21

10. APPARENT EPICYCLIC ORBITS OF JUPITER AND SATURN 22

11. EGYPTIAN SYSTEM 24

12. TRUE ORBITS OF EARTH AND JUPITER 25

13. ORBITS OF MERCURY AND EARTH 25

14. COPERNICAN SYSTEM AS FREQUENTLY REPRESENTED 26

15. SLOW MOVEMENT OF THE NORTH POLE IN A CIRCLE AMONG
THE STARS 29

16. TYCHONIC SYSTEM, SHOWING THE SUN WITH ALL THE PLANETS
REVOLVING ROUND THE EARTH 38

17. PORTRAIT OF TYCHO 41

18. EARLY OUT-DOOR QUADRANT OF TYCHO 43

19. MAP OF DENMARK, SHOWING THE ISLAND OF HUEN 45

20. URANIBURG 46

21. ASTROLABE 47

22. TYCHO'S LARGE SEXTANT 48

23. THE QUADRANT IN URANIBURG 49

24. TYCHO'S FORM OF TRANSIT CIRCLE 50

25. A MODERN TRANSIT CIRCLE 51

26. ORBITS OF SOME OF THE PLANETS DRAWN TO SCALE 60

27. MANY-SIDED POLYGON OR APPROXIMATE CIRCLE ENVELOPED
BY STRAIGHT LINES 61

28. KEPLER'S IDEA OF THE REGULAR SOLIDS 62

29. DIAGRAM OF EQUANT 67

30. EXCENTRIC CIRCLE SUPPOSED