SECTION II.. What Are the Changes Which Are to Be Referred to Chemical Agency?

What are the changes which are to be referred to chemical agency?

Mention some of the disturbances which give rise to chemical changes.

What are the principal effects of chemical action?

How is the cleavage structure accounted for?

Mention instances which show that a cleavage may be established in a body in a solid state.

In it a crystalline arrangement of the particles of the mass?

What other divisional planes exist in rocks?

Mention instances of concretionary formations.

Why may not these concretions have been deposited as nodules?

How have these concretions been formed?

Mention instances of segregation without the concretionary structure.

How was the segregation in these instances effected?

How is the columnar structure produced?

What is the origin of the mineral veins which are first mentioned?

How is it shown that other veins are not injected?

How were these veins formed?

What is the force by which these molecular changes have been effected?