xiv ; CONTENTS 
CHAPTER VII. Winp Erosion 
Use of the Word Wind Erosion 
Mode of Wind Action 
Sand Dunes 
Erosive Action . 
CHAPTER VIII. UnpERGROUND WATER 
General Importance . 
Limestone Caves 
Landslips 
Springs : 
Artesian Wells . 
CHAPTER IX. River Erosion 
Rain Erosion : 
Supply of River Water 
Chemical Action 
Mechanical Action 
Cutting Tools 
Intermittent Work 
Valley Deepening ; 
Codperation of Weathering 
Waterfalls . ; ; 
The Colorado Cafion . 
CHAPTER X. River anp LAKE DEposits 
River Deposits 
Transportation of Sediment ; 
Alluvial Fans or Cones (Cone Deltas) 
Bars 
Floodplains 
Terraces 
Deltas 
Lakes 
Cause and Condition 
Filling with Sediment ; : : . . . . . 
PAGE 
129 
129 
131 
135 
139 
140 
143 
145 
147 
151 
155 
156 
158 
158 
161 
163 
165 
167 
170 
174 
176 
177 
178 
180 
180 
188 
188 
