The picture on the top shows the method of construction.
MASSIVE CONCRETE WORK
Completed side walls of solid concrete in the Gatun Locks of the Panama Canal.
A LEVEL STRETCH OF CATSKILL AQUEDUCT
Showing completed section as well as forms for the concrete.
On entering the cement show our friends saw on every side long rows of booths showing models of structures and articles that could be made of concrete. There were models of houses, subways, dams, bridges, dock works, retaining walls, sewers, bridges, pavements and even boats and furniture. In fact, so the men in the exhibition booths said, concrete can be used for practically every building purpose where strength, lasting qualities, and resistance to heat and cold are needed. "This is the concrete age," they declared. "Concrete is fireproof, waterproof, sanitary, and resists frost when properly used. Our timber supply is decreasing, the supply of iron ore for structural steel is limited, and stone is expensive; so concrete, reinforced with steel, and used by engineers who understand their business, will be the greatest building material of the future."