Chapter II: Part I

ASTRONOMY FROM PRIMITIVE TIMES UNTIL THE AGE OF DANTE.

I. APPARENT MOVEMENTS OF THE HEAVENLY BODIES AS SEEN
FROM EARTH 9

II. THE BEGINNINGS OF ASTRONOMY. Gnomons and
clepsydras; the constellations and the calendar;
astrology and star-worship; early cosmogonies 25

III. GREEK ASTRONOMY: FIRST PERIOD.
B.C. 900 to B.C. 350
1. Homeric Greece; First Notions of Astronomy 51
2. Thales and Anaximander: Earth flat, heaven a
series of hemispheres 55
3. Later Flat Earth Systems: the Universe a sphere 60
4. Pythagoras and his Followers: Earth round,
Earth in Motion 66

IV. GREEK ASTRONOMY: SECOND PERIOD,
B.C. 400 to A.D. 150
1. Plato: the World-Soul 79
2. Eudoxus: the Spheres 88
3. Calippus: the Spheres of Eudoxus improved 93
4. Aristotle: the Philosophy of the Spheres; the
three kinds of motion; Earth immoveable at the
centre of the Universe; the elements; the
celestial movers, and the First Mover 95
5. Aristarchus: Earth turning on her axis, and
revolving round the sun 107
6. The School of Alexandria: instruments and
methods; Earth’s diameter measured; the theory
of Moveable Eccentrics 112
7. Hipparchus: “the Father of Astronomy;” his
star catalogue; his inventions and discoveries;
the precession of the equinoxes 122
8. Ptolemy: the Almagest; the system of Epicycles
and Eccentrics; distance and size of the moon
discovered; the stars; astrology; geography, the
seven climates 134
V. RETROSPECT: Greek Cosmogonies; Greek calendar 159
VI. ASTRONOMY UNDER IMPERIAL AND CHRISTIAN ROME.
B.C. 46 to A.D. 1000. Amateur
Astronomers; the Julian Calendar; passion for
Astrology; the Fathers; the ecclesiastical Calendar;
the Schools; the Monasteries 167
VII. ARAB ASTRONOMY. A.D. 750 to 1250.
Schools of Baghdad, Egypt, Spain. Improvements in
Mathematics and Instruments; Ptolemy’s values more
correctly determined; supposed discoveries of
planetary distances and trepidation; a ninth sphere
added to Ptolemy’s eight 181
VIII. THE RETURN OF GREEK ASTRONOMY TO EUROPE.
A.D. 1000 to 1300. The Universities;
Arab influence; Greek books; new European books;
the course in Astrology in Bologna; Aristotle and
the Church 199