The scale of the universe—The solar system—Regions of the sun—The surface of the sun—Measuring the speed of light—Is the sun dying?—The planets—Venus—Is there life on Mars?—Jupiter and Saturn—The moon—The mountains of the moon—Meteors and comets—Millions of meteorites—A great comet—The stellar universe—The evolution of stars—The age of stars—The nebular theory—Spiral nebulÆ—The birth and death of stars—The shape of our universe—Astronomical instruments.
The beginning of the earth—Making a home for life—The first living creatures—The first plants—The first animals—Beginnings of bodies—Evolution of sex—Beginning of natural death—Procession of life through the ages—Evolution of land animals—The flying dragons—The first known bird—Evidences of evolution—Factors in evolution.
Anatomical proof of man's relationship with a Simian stock—Physiological proof—Embryological proof—Man's pedigree—Man's arboreal apprenticeship—Tentative men—Primitive men—Races of mankind—Steps in human evolution—Factors in human progress.
Evolutionary prospect for man—The fountain of change; variability—Evolution of plants—Romance of wheat—Changes in animal life—Story of the salmon—Forming new habits—Experiments in locomotion; new devices.
A caution in regard to instinct—A useful law—Senses of fishes—The mind of a minnow—The mind and senses of amphibians—The reptilian mind—Mind in birds—Intelligence co-operating with instinct—The mind of the mammal—Instinctive aptitudes—Power of association—Why is there not more intelligence?—The mind of monkeys—Activity for activity's sake—Imitation—The mind of man—Body and mind.
The world of atoms—The energy of atoms—The discovery of X-rays—The discovery of radium—The discovery of the electron—The electron theory—The structure of the atom—The new view of matter—Other new views—The nature of electricity—Electric current—The dynamo—Magnetism—Ether and waves—Light—What the blue "sky" means—Light without heat—Forms of energy—What heat is—Substitutes for coal—Dissipation of energy—What a uniform temperature would mean—Matter, ether, and Einstein—The tides—Origin of the moon—The earth slowing down—The day becoming longer.
