The particular features which, it is hoped, may give the book a distinctive place in the large literature of evolution are, first, that it includes the many evolutionary discoveries of the last few years, gathers its material from the score of sciences which confine themselves to separate aspects of the universe, and blends all these facts and discoveries in a more or less continuous chronicle of the life of the heavens and the earth. Then the author has endeavoured to show, not merely how, but why, scene succeeds scene in the chronicle of the earth, and life slowly climbs from level to level. He has taken nature in the past as we find it to-day: an interconnected whole, in which the changes of land and sea, of heat and cold, of swamp and hill, are faithfully reflected in the forms of its living population. And, finally, he has written for those who are not students of science, or whose knowledge may be confined to one branch of science, and used a plain speech which assumes no previous knowledge on the reader's part. For the rest, it will be found that no strained effort is made to trace pedigrees of animals and plants when the material is scanty; that, if on account of some especial interest disputable or conjectural speculations are admitted, they are frankly described as such; and that the more important differences of opinion which actually divide astronomers, geologists, biologists, and anthropologists are carefully taken into account and briefly explained. A few English and American works are recommended for the convenience of those who would study particular chapters more closely, but it has seemed useless, in such a work, to give a bibliography of the hundreds of English, American, French, German, and Italian works which have been consulted. CONTENTS I. THE DISCOVERY OF THE UNIVERSE II. THE FOUNDATIONS OF THE UNIVERSE III. THE BIRTH AND DEATH OF WORLDS IV. THE PREPARATION OF THE EARTH V. THE BEGINNING OF LIFE VI. THE INFANCY OF THE EARTH VII. THE PASSAGE TO THE LAND VIII. THE COAL-FOREST IX. THE ANIMALS OF THE COAL-FOREST X. THE PERMIAN REVOLUTION XI. THE MIDDLE AGES OF THE EARTH XII. THE AGE OF REPTILES XIII. THE BIRD AND THE MAMMAL XIV. IN THE DAYS OF THE CHALK XV. THE TERTIARY ERA XVI. THE FLOWER AND THE INSECT XVII. THE ORIGIN OF OUR MAMMALS XVIII. THE EVOLUTION OF MAN XIX. MAN AND THE GREAT ICE-AGE XX. THE DAWN OF CIVILISATION XXI. EVOLUTION IN HISTORY INDEX THE STORY OF EVOLUTION CHAPTER I. THE DISCOVERY OF THE UNIVERSE