A line of female workers use pneumatic hammers on bench in the ordnance shop at the Midvale Steel and Ordnance Company, Nicetown, Pennsylvania, 1918. (Photo by Interim Archives/Getty Images)
A line of female workers use pneumatic hammers on bench in the ordnance shop at the Midvale Steel and Ordnance Company, Nicetown, Pennsylvania, 1918. (Photo by Interim Archives/Getty Images)