CONTENTS 



INTRODUCTION 



PART I 

 PHYSICAL GEOLOGY 



I. THE COMPOSITION OF THE EARTH ... 13 



THE GKEAT DIVISIONS OF THE EARTH . . . .13 



THE MATERIALS OF THE LITHOSFHERE .... 16 



SURFACE STRUCTURES OF IGNEOUS ROCKS ... 46 



QUESTIONS . . . ,57 



REFERENCES ,59 



II. PHYSICAL CHANGES OF THE OUTER SHELL . 61 



EFFECTS OF MOVEMENTS 65 



FOLDS 66 



FRACTURES 70 



UNCONFORMITIES 75 



VULCANISM 76 



ZONES OF FRACTURE AND FLOW AGE 77 



How ROCKS ARE ALTERED ....... 78 



QUESTIONS 83 



REFERENCES .......... 85 



III. THE WORK OF THE ATMOSPHERE ... 86 



MECHANICAL WORK 86 



CHEMICAL WORK 103 



SUMMARY 104 



QUESTIONS 105 



REFERENCES .......... 106 



IV. THE WORK OF WATERS UNDERGROUND . . 107 



FACTS ABOUT GROUND WATER 107 



SPRINGS AND UNDERGROUND CIRCULATION . . . 110 



THE WORK OF GROUND WATKK 114 



QUESTIONS 123 



REFERENCES 124 



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