Describe the principal lines of volcanic activity.
What are the forces tending to repress the elasticity of the mass below?
What will be the effect when the elastic is greater than the repressing force?
What produces the phenomena of the earthquake?
What is a volcano?
Why are volcanoes generally arranged a linear direction?
Under what circumstances will a new volcano be formed?
What instances are cited?
How is a volcanic cone formed?
Why are lateral cones produced?