CHAPTER V. LAND SCULPTURE 99 I. Erosion 99 A. Processes of erosion 99 Weathering 100 Transportation 101 Corrasion 101 B. Conditions controlling erosion 102 Rate of erosion and declivity 102 Rate of erosion and rock texture 103 Rate of erosion and climate 103 Transportation and comminution 106 Transportation and declivity 108 Transportation and quantity of water 109 Corrasion and transportation 111 Corrasion and declivity 112 Declivity and quantity of water 113 II. Sculpture 115 Sculpture and declivity 115 The law of structure 115 The law of divides 116 Sculpture and climate 117 Bad-lands 120 Equal action and interdependence 123 III. Systems of drainage 124 The stability of drainage lines 124 The instability of drainage lines 125 The stability of divides 138 The instability of divides 139 Consequent and inconsequent drainage 143 The drainage of the Henry Mountains 144 CHAPTER VI. ECONOMIC 151 CHAPTER I. INTRODUCTORY.