Public domain
Untitled photo, possibly related to: Wilson Dam, Alabama (Tennessee Valley Authority (TVA)). Tapping the slag at a phosphorus furnace at a chemical plant
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineUntitled photo, possibly related to: Wilson Dam, Alabama (Tennessee Valley Authority (TVA)). Tapping the slag at a phosphorus furnace at a chemical plant. 1935-01-01. Rothstein, Arthur. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.