Old Shot Tower in Dubuque
Old shot tower in Dubuque. Photo was taken in April, 1940. In the late 1700s and early 1800s lead mines produced valuable ore in the Dubuque area. Lead bullets were produced in a shot tower. Molten lead was dropped from the top of the tower into water at the bottom. Like raindrops, the hot lead would form into perfect spheres, cool and solidify as they fell into the cooling water.
Photographer: John Vachon. Library of Congress, Prints & Photographs Division, FSA-OWI Collection.