CONTENTS.


CHAPTER I.

ON THE DIFFERENT CLASSES OF ROCKS.

Geology defined.
Successive Formation of the Earth's Crust.
Classification of Rocks according to their Origin and Age.
Aqueous Rocks.
Their Stratification and imbedded Fossils.
Volcanic Rocks, with and without Cones and Craters.
Plutonic Rocks, and their Relation to the Volcanic.
Metamorphic Rocks, and their probable Origin.
The term Primitive, why erroneously applied to the Crystalline Formations.
Leading Division of the Work.


CHAPTER II.

AQUEOUS ROCKS-- THEIR COMPOSITION AND FORMS OF STRATIFICATION.

Mineral Composition of Strata.
Siliceous Rocks.
Argillaceous.
Calcareous.
Gypsum.