URL: https://digitalcollections.hoover.org/objects/37485 Collection Structure Poster collection > Our three lines of national defense. The smoke of America's factory stacks is a signal of our workers' and employers' loyalty. It means more guns - more ships - more food. Our industries are our third and main supporting line of defense - our base of supplies. ... Item Title Our three lines of national defense. The smoke of America's factory stacks is a signal of our workers' and employers' loyalty. It means more guns - more ships - more food. Our industries are our third and main supporting line of defense - our base of supplies. ... Collection Title Poster collection Artist Peckner, A. Issuing Body National Industrial Conservation Movement Date Created 1914/1918? Description Sketch of factories, workers, soldiers. Subject(s) Priorities, Industrial Efficiency, Industrial Industrial relations Supplies and stores United States Economic aspects Manpower Industrial productivity World War, 1914-1918 Language(s) English Country of Origin United States Country of Origin United States Dimensions Overall: 25 x 19 in. (63.5 x 48.3 cm) Format Poster Medium political posters Color black and white Color black and white Hoover ID Poster US 4268 Record Number XX343.27861 Collection Guide https://oac.cdlib.org/findaid/ark:/13030/kt829015km Rights No known restrictions.