CONTENTS

Part I—The Celestial Sphere.

PAGES
Definition of Astronomy—Fundamental Law of the Stars—Relations of the Earth to the Universe—Ordinary Appearance of the Sky—The Horizon, the Zenith, and the Meridian—Locating the Stars—Altitude and Azimuth—Circular or Angular Measure—Altitude Circles and Vertical Circles—The Apparent Motion of the Heavens—The North Star and Phenomena Connected with it—Revolution of the Stars round the Pole—Locating the Stars on the Celestial Sphere—Astronomical Equivalents of Latitude and Longitude—Parallels of Declination and Hour Circles—“The Greenwich of the Sky”—Effects Produced by Changing the Observer's Place on the Earth—The Parallel Sphere, the Right Sphere, and the Oblique Sphere—The Astronomical Clock—The Ecliptic—Apparent Annual Revolution of the Sun round the Earth—Inclination of the Ecliptic to the Equator: its Cause and its Effects—The Equinoxes—Importance of the Vernal Equinox—The Equinoctial Colure—The Solstices—Poles of the Ecliptic—Celestial Latitude and Longitude—The Zodiac—The Precession of the Equinoxes: its Cause and Effects—Revolution of the Celestial Poles—Past and Future Pole Stars[3]-[64]

Part II—The Earth.

PAGES
Nature, Shape, and Size of the Earth—The Polar Compression and Equatorial Protuberance, and their Cause—The Attraction of Gravitation—The Mass of the Earth: how Found—How the Earth Holds the Moon, and the Sun the Planets—The Tides—How the Moon and Sun Produce Tides—Spring Tides and Neap Tides—The Atmosphere—The Law and Effects of Refraction—Dip of the Horizon—The Aberration of Light—Time: how Measured—Sidereal, Apparent Solar, and Mean Solar Time—The Clock and the Sun—Day and Night—Where the Days Begin—The Seasons—Effects of the Varying Declination of the Sun—Polar and Equatorial Day and Night—The Tropics and the Polar Circles—Inequality of Length of the Seasons—When the Seasons in the Two Hemispheres will be Reversed—The Calendar, the Year, and the Month—Reformations of the Calendar—Different Measures of the Month[67]-[123]

Part III—The Solar System.

PAGES
The Sun—Distance, Size, and Condition of the Sun—Temperature of the Sun—Solar Heat on the Earth, and its Mechanical Equivalent—Peculiar Rotation of the Sun—Sun-spots, their Appearance and Probable Cause—Faculæ—The Photosphere—Solar Prominences—Explosive Prominences—The Solar Corona—Parallax, and the Measure of Distances—Spectroscopic Analysis—How the Elements in the Sun Reveal their Presence—List of the Principal Solar Elements—The Moon—Origin of the Moon—Appearance of its Surface—Gravity on the Moon—The Phases of the Moon—Causes of the Absence of a Lunar Atmosphere—Eclipses—How the Moon Causes Eclipses of the Sun—The Laws Governing Eclipses—The Shadow during a Solar Eclipse—Eclipses of the Moon—Number of Eclipses in a Year—The Saros—The Planets—Kepler's Laws of Planetary Motion—Mercury—Venus—Mars, and its So-called Canals—Theories about Mars—Jupiter, its Belts and its Satellites—The "Great Red Spot”—Saturn, its Rings and its Satellites—Composition of the Rings—Uranus and Neptune—Comets, and the Laws of their Motion—Composition of Comets—The Pressure of Light and its Connection with Comets' Tails—Breaking up of Comets—Meteors and their Relations to Comets—The November Meteors and Other Celebrated Showers—Meteorites or Bolides which Fall upon the Earth—The Question of their Origin[127]-[215]

Part IV—The Fixed Stars.

PAGES
Division of the Stars into Magnitudes—Division of the Stars according to their Spectra—Stars Larger and Smaller than the Sun—The Distances of the Stars—Variable Stars—Double and Binary Stars—Spectroscopic Binaries and how they are Discovered—Proper Motions of the Stars—Number of the Stars—New, or Temporary Stars—The Milky Way—The Nebulæ—The Two Kinds of Nebulæ—Spiral Nebulæ—The Nebular Hypothesis—Applications of Photography to Stars and Nebulæ—The Constellations—How to Learn the Constellations—Their Antiquity—Description of the Principal Constellations Visible from the Northern Hemisphere at Various Times of the Year[219]-[257]
Index[259]