Original World War 2 plastic industry trade magazine vintage ad for PORTLAND CEMENT ASSOCIATION of Chicago, IL. Webster has a word for Concrete.  Concrete is truly the Structural Plastic.  Today concrete is being molded to the pattern of war, runways for bombers, warehouses for Army and Navy stores, factories for the building of tanks, planes, guns.   Old 1943 dated WW2 wartime era propaganda magazine advertisement.