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.