Reinforced concrete blocks.

Concrete

Reinforced concrete blocks.

This illustration shows a rock made up of all kinds of concretionary objects.

Concretionary Structure

This illustration shows a rock made up of all kinds of concretionary objects.

A machine capable of pressure of 2,000 tons. It is able to cold form metal, and is used to make material for the concrete industry.

Hydraulic Press

A machine capable of pressure of 2,000 tons. It is able to cold form metal, and is used to make material…

An example of a set of concrete steps.

Concrete Steps

An example of a set of concrete steps.

"Single-course pavement is usually made five inches thick. Proportions for this should be 1:2:3. Concrete for a single course should be mixed to such a consistency that enough mortar will rise to the surface on light tamping to permit of finishing with a wooden float."—The Federal Digest, 1921

One-Course Work

"Single-course pavement is usually made five inches thick. Proportions for this should be 1:2:3. Concrete…

"For two-course floors and pavements, a concrete base of about four inches thick, mixed 1:3:5 (that is, one sack of cement, 3 cubic feet of sand, and 5 cubic feet of gravel), is first placed in the forms."—The Federal Digest, 1921

Two-Course Work

"For two-course floors and pavements, a concrete base of about four inches thick, mixed 1:3:5 (that…