Public domain
Washington, D.C. Test pile loaded with concrete blocks to determine how much the pile will sink when the bridge structure is finished
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineWashington, D.C. Test pile loaded with concrete blocks to determine how much the pile will sink when the bridge structure is finished. 1942-01-01. Ferrell, John. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.