The interest of the beginner in geology is sure to be aroused when he comes to see how very far the history of the earth has influenced the fate of men. Therefore the aim has been, where possible, to show the ways in which geological processes and results are related to ourselves; how, in a word, this earth has been the well-appointed nursery of our kind. All those who are engaged in teaching elementary science learn the need of limiting the story they have to tell to those truths which can be easily understood by beginners. It is sometimes best, as in stating such difficult matters as those concerning the tides, to give explanations which are far from complete, and which, as to their mode of presentation, would be open to criticism were it not for the fact that any more elaborate statements would most likely be incomprehensible to the novice, thus defeating the teacher's aim. It will be observed that no account is here given of the geological ages or of the successions of organic life. Chapters on these subjects were prepared, but were omitted for the reason that they made the story too long, and also because they carried the reader into a field of much greater difficulty than that which is found in the physical history of the earth. N.S.S. _March, 1898._ CONTENTS. CHAPTER PAGE I.--INTRODUCTION TO THE STUDY OF NATURE 1 II.--WAYS AND MEANS OF STUDYING NATURE 9 III.--THE STELLAR REALM 31 IV.--THE EARTH 81 V.--THE ATMOSPHERE 97 VI.--GLACIERS 207 VII.--THE WORK OF UNDERGROUND WATER 250 VIII.--THE SOIL 313 IX.--THE ROCKS AND THEIR ORDER 349 LIST OF FULL-PAGE ILLUSTRATIONS. FACING PAGE Dunes at Ipswich Light, Massachusetts _Frontispiece_ Seal Rocks near San Francisco, California 33 Lava stream, in Hawaiian Islands, flowing into the sea 72 Waterfall near Gadsden, Alabama 90 South shore, Martha's Vineyard, Massachusetts 121 Pocket Creek, Cape Ann, Massachusetts 163 Muir Glacier, Alaska 207 Front of Muir Glacier 240 Mount AEtna, seen from near Catania 201 Mountain gorge, Himalayas, India 330 OUTLINES OF THE EARTH'S HISTORY. CHAPTER I. AN INTRODUCTION TO THE STUDY OF NATURE.