CONTENTS 
Organic Rocks . 
Caleareous Rocks 
Silicious Rocks 
Phosphate Rocks 
Plant Deposits 
Other Organic Rocks . 
Importance of Sedimentary Rocks 
Metamorphic Rocks 
Nature of the Process 
Results of Metamorphism . 
Complexity of Metamorphism . 
Characteristics of Metamorphic Rocks 
Part Il. Dynamic GEOLOGY 
CHAPTER VI. WeraTHERING 
Denudation 
Effect of Climate 
Presence of Water 
Mechanical Agents 
Frost Action 
Effect of Heat : 
Effect of Moisture and Dryaens 
Action of Plants . 
Action of Burrowing nteeals 
Chemical Agents 
Percolating Water 
Action of Plants . . 
Evidence of Chemical Changes ; 
The Soils 
Residual Soil 
Other Soils . : 
Absence of Soils on Mountains ; 
Soil Protection 
Forest Protection 
Formation of Talus 
Difference in Rate of Weathering 
Importance of Weathering 
Xili 
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