John Ericsson Memorial

From www.nps.gov:

Ericsson, an immigrant from Sweden, revolutionized the very concept of naval propulsion, with his development of the screw propeller. His love for the republican values of the United States manifested itself throughout the American Civil War. Ericsson's ship, the U.S.S. Monitor, helped to preserve the blockade effort of the United States Navy and ensured Yankee naval supremacy.