292

XX. ORION AND HIS NEIGHBOURS " " 296

XXI. THE GREAT GLOBULAR CLUSTER
IN THE SOUTHERN CONSTELLATION
OF CENTAURUS " " 306

XXII. SPIRAL NEBULA IN THE CONSTELLATION
OF CANES VENATICI " " 314

XXIII. THE GREAT NEBULA IN THE
CONSTELLATION OF ANDROMEDA _To face page_ 316

XXIV. THE GREAT NEBULA IN THE
CONSTELLATION OF ORION " " 318

LIST OF DIAGRAMS

FIG. PAGE
1. THE PTOLEMAIC IDEA OF THE UNIVERSE 19

2. THE COPERNICAN THEORY OF THE SOLAR
SYSTEM 21

3. TOTAL AND PARTIAL ECLIPSES OF THE MOON 64

4. TOTAL AND PARTIAL ECLIPSES OF THE SUN 67

5. "BAILY'S BEADS" 70

6. MAP OF THE WORLD ON MERCATOR'S PROJECTION,
SHOWING A PORTION OF THE PROGRESS
OF THE TOTAL SOLAR ECLIPSE OF
AUGUST 30, 1905, ACROSS THE SURFACE
OF THE EARTH 81

7. THE "RING WITH WINGS" 87

8. THE VARIOUS TYPES OF TELESCOPE 113

9. THE SOLAR SPECTRUM 123

10. A SECTION THROUGH THE SUN, SHOWING HOW
THE PROMINENCES RISE FROM THE
CHROMOSPHERE 131

11. ORBIT AND PHASES OF AN INFERIOR PLANET 148

12. THE "BLACK DROP" 153

13. SUMMER AND WINTER 176

14. ORBIT AND PHASES OF THE MOON 184

15. THE ROTATION OF THE MOON ON HER AXIS 187

16. LAPLACE'S "PERENNIAL FULL MOON" 191

17. ILLUSTRATING THE AUTHOR'S EXPLANATION OF
THE APPARENT ENLARGEMENT OF CELESTIAL
OBJECTS 195

18. SHOWING HOW THE TAIL OF A COMET IS
DIRECTED AWAY FROM THE SUN 248

19. THE COMET OF 1066, AS REPRESENTED IN THE
BAYEUX TAPESTRY 263

20. PASSAGE OF THE EARTH THROUGH THE THICKEST
PORTION OF A METEOR SWARM 269

ASTRONOMY OF TO-DAY

CHAPTER I

THE ANCIENT VIEW

It is never safe, as we know, to judge by appearances, and this is
perhaps more true of astronomy than of anything else.

For instance, the idea which one would most naturally form of the earth
and heaven is that the solid ea