CONTENTS 



PART I 



THE MATERIALS OF THE EARTH AND PROCESSES 

 WHICH AFFECT THEM 



CHAPTER PAG E 



I. PRELIMINARY OUTLINE 



THE EARTH IN THE SOLAR SYSTEM 2 



THE GRAND DIVISIONS OF THE EARTH 4 



II. GEOLOGIC WORK OF THE ATMOSPHERE 



MECHANICAL WORK 12 



CHEMICAL WORK 23 



THE ATMOSPHERE AS A CONDITIONING AGENCY .... 25 



SUMMARY 29 



III. WORK OF GROUND (UNDERGROUND) WATER 



GENERAL FACTS 30 



WORK OF GROUND-WATER 35 



ORE DEPOSITS 4 



SUMMARY 47 



SPRINGS AND ARTESIAN WELLS 48 



IV. WORK OF RUNNING WATER 



EROSIVE WORK 59 



ANALYSIS OF EROSION 73 



CONDITIONS AFFECTING RATE OF EROSION 80 



RATE OF DEGRADATION 84 



FEATURES RESULTING FROM SPECIAL CONDITIONS OF ERO- 

 SION 84 



EFFECTS OF UNEQUAL HARDNESS . 89 



THE EROSION OF FOLDS 95 



ADJUSTMENT OF STREAMS TO ROCK STRUCTURES .... 97 



INFLUENCE OF JOINTS ON EROSION 99 



EFFECT OF CHANGES OF LEVEL 101 



AGGRADATIONAL WORK OF RUNNING WATER 107 



ALLUVIAL TERRACES 118 



V. WORK OF SNOW AXD ICE 



ICE IN GENERAL 121 



GLACIERS 127 



THE STRUCTURE OF GLACIER ICE . 139 



MOTION OF GLACIER ICE 142 



THE WORK OF GLACIERS ... 147 



GLACIO-FLUVIAL WORK 164 



ICEBERGS 166 



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