All solids must have length, breadth, and thickness.

Do solids vary much in length, breadth, and thickness?

Yes; they vary so much that we can scarcely find two things exactly alike in shape and size.

Can the shape of any substance be changed?

Yes; its shape may be changed in many ways.

What takes place in india-rubber when it is stretched?

Its particles are drawn farther apart, and its shape is altered.

When the force is removed, what does the india-rubber do?

It springs back into its former shape.

What is this property of the india-rubber called?