ILLUSTRATIONS.

PART I.
FIG.PAGE

Dante Studying.From a fresco by Luca Signorelli at Orvieto

[Frontispiece]
1.The Sun’s Path in the Sky at different Seasons[11]
2.The Moon at Sunset, soon after New, and three days old[14]
3.Path of Mars among the Stars, 1909[16]
4.The Star Sphere[19]
5.Synodic and Sidereal Periods[21]

Star Map

[34]

The Moon-God of Ur. From a Cylinder-seal in the British Museum, date about b.c. 2400. By permission of the Trustees of the British Museum

[36]
6.The triple Star-sign of the Babylonians[37]
7, 8, 9.The young Moon and the Pleiades after sunset, as seen in Babylon, b.c. 1000[42]
10.

The Scorpion. From a Babylonian boundary stone of aboutb.c. 1120, set up in the reign of Nebuchadnezzar I. Now in the British Museum

[43]
11.

The Goat with Fishes’ Scales. From a Babylonian boundary stone

[43]

The Boat of the Sun travelling over the Sky.From an ancient Egyptian papyrus. Reproduced from Flammarion’s Astronomical Myths

[46]
12.The Universe according to Anaximander[59]
13.The Universe of Leucippus[63]
14.The Universe of Democritus[64]
15.The Universe of Pythagoras[71]
16.The System of Philolaus: night on Earth[73]
17.do.twelve hours later: day on Earth[73]
18.Earth and Sun according to Heraclides[74]
19.The Spheres of the Sun in the system of Eudoxus[90]
20.Method of Aristarchus for finding the Distance of the Sun[108]
21.Pekin Observatory[114]
22.

A Pekin Astrolabe of the thirteenth century a.d.From photographs taken in 1888 and published in the Bulletin de la Société belge d’Astronomie

[116]
23.The Moveable Eccentric[119]
24.The Movement of Spica[124]
25.The Sun and the Equinox[128]
26.

The Movement of the Earth’s Axis which is the true cause of Precession. From Young’s Manual of Astronomy, 1902

[131]
27.Precession of the Equinoxes[133]
28.Path of Mars, 1909[139]
29.The Epicycle[139]
30.A Planet “retrograding” and “in opposition”[140]
31.Venus, Mercury, and the Sun[142]
32.The Sun’s Deferent[145]
33.

Apparent Variation in the size of the Sun. Photographs taken at Kodaikanal Observatory, with the spectroheliograph, July 1, 1911, and Jan. 3, 1912. Actual size of the negative

[146]
34.The Moon’s Epicycle and Deferent[148]
35.The Ptolemaic System[151]
36.

Method (erroneous) of estimating Planetary Distances, described by Alfraganus

[188]
37.Earth’s Shadow[192]
PART II.
FIG.PAGE

A Mediæval Astronomer.From a painting by Gerard Dow

[200]

Astronomy.From a fresco in the Spanish Chapel of Santa Maria Novella, Florence

[217]
38.The Half-Moon shape of the Habitable Earth (Ristoro)[247]

Climate Map of about a.d. 1110. Reproduced from Beazley’s Dawn of Modern Geography

[248]
39.Sun, Moon, and zenith. To illustrate Par. xxix 1-6[267]
40.The Zodiac and the Months[276]
41.

The Ram on the Ecliptic. From the Cosmi Historia of Robert Flud, a.d. 1612. Reproduced from Brown’s Aratos.

[279]

Map of Stars visible before Dawn in Purgatory

[295]
42.Ursa Minor as a Horn. Par. xiii. 10[299]
43.The Sun at the Equinox, seen from the poles and the equator. Conv. III. v.[327]
44.Lunar and Solar Eclipses[339]

Map of the World by Heinrich of Mainz, about a.d. 1110. Reproduced from Beazley’s Dawn of Modern Geography

[344]
45.The Universe of Dante[355]
46.The Signs of the Zodiac at sunrise from the Mountain of Purgatory[375]
47.Northern Slope of the Mountain of Purgatory[377]
48.Dante’s View of Earth from the stars. Par. xxii.[395]
49.do. Six hours later. Par. xxvii.[396]
50.An impossible interpretation of Par. xxvii.[399]
51.The Rising Sun at the spring equinox. Par. i. 39[403]
52.The Moon’s Epicycle and Deferent[449]
53.Comparative sizes of the Sun and his satellites[490]

ABBREVIATED TITLES OF
BOOKS USED IN THE TEXT.

Dante’s Works:—
Inf.Inferno.
Purg.Purgatorio.
Par.Paradiso.
Canz.Canzone.
Son.Sonetto.
Ball.Ballata.
Ecl.Eclogue.
V. N.Vita Nuova.
Conv.Convivio.
De Mon.De Monarchia.
V. E.De Vulgari Eloquentia.
Ep.Epistola.
Qu.Quæstio de Aqua et Terra.
El. Ast.Elementa Astronomica (Alfraganus).
Comp. del Mond.Della Composizione del Mondo (Ristoro).

Dante and the
Early Astronomers.