STODIES FOR STUDENTS. 
DERORWATION (OR (ROCKS lk AN VANAINY SIS @k 
HOD S: 
CONTENTS. 
Simple folds. 
Composite folds. 
Normal composite folds. 
The upright normal anticlinorium. 
The inclined normal anticlinorium. 
The overturned normal anticlinorium. 
The upright normal synclinorium. 
The inclined normal synclinorium. 
The overturned normal synclinorium. 
Abnormal composite folds. 
The upright abnormal anticlinorium. 
The inclined abnormal anticlinorium. 
The overturned abnormal] anticlinorium. 
The upright abormal synclinorium. 
The inclined abnormal synclinorium. 
The overturned abnormal synclinorium. 
Occurrence and origin of composite folds. 
Higher orders of folds. 
Origin of normal folds. 
Origin of abnormal folds. 
Causes modifying the forms of folds. 
Examples of composite folds. 
Limit of term fold. 
Movements continuous or discontinuous. 
Complex folds. 
Origin of complex folds. 
Character of complex folds. 
Observations in complexly folded districts. 
Changes accompanying folding. 
Relations of folds and unconformity. 
As ordinarily treated, folds are considered as simple flexures 
in two dimensions. As they occur in nature, folds are complex 
flexures in three dimensions. 
Folds in rocks may be compared with the waves of the sea. 
Each large wave has superimposed upon it waves of the second 
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