CONTENTS 
BOOK I 
GENEEAL PEINCIPLES AKD METHODS OF INYESTIGATIOK 
CHAPTEE I 
Earliest Knowledge of Volcanoes — Their Influence on Mythology and Superstition — Part 
taken by Volcanic Rocks in Scenery — Progress of the Denudation of Volcanoes — 
Value of the Records of former Volcanoes as illustrating Modern Volcanic Action — 
Favourable Position of Britain for the Study of this Subject . . . . 
CHAPTEE H 
The Nature 
and Causes of Volcanic Action — Modern Volcanoes 
10 
CHAPTEE HI 
Ancient Volcanoes : Proofs of their existence derived from the Nature of the Rocks erupted 
from the Earth’s Interior. A. Materials erupted at the Surface — Extrusive Series, 
i. Lavas, their General Characters. Volcanic Cycles, ii. Agglomerates, Breccias 
and Tuffs ........... 14 
CHAPTEE IV 
Materials erupted at the Surface — Extrusive Series — continu-ed. iii. Types of old Volcanoes 
— 1. The Vesuvian Type ; 2. The Plateau or Fi.ssure Type; 3. The Puy Tjqie. iv. 
Determination of the relative Geological Dates of Ancient Volcanoes, v. How the 
Physical Geography associated with Ancient Volcanoes is ascertained . . 39 
CHAPTEE V 
Underground Phases of Volcanic Action. B. Materials injected or consolidated beneath the 
Surface — Intrusive Series : I. Vents of Eruption — i. Necks of Fragmentary 
Materials ; ii. Necks of Lava-form Materials ; iii. Distribution of Vents in relation to 
Geological Structure-Lines ; iv. Metainorphism in and around Volcanic Cones, Sol- 
