Book Ii.--the Physical Sciences in Ancient Greece.

Plato's Timæus and Republic. 497 Hero of Alexandria. 501

BOOK III.--THE GREEK ASTRONOMY.

Introduction. 503

EARLIEST STAGES OF ASTRONOMY.

The Globular Form of the Earth. 505 The Heliocentric System among the Ancients. 506 The Eclipse of Thales. 508 {21}