Civil War Union Naval Officer. He commanded the ironclad "USS Monitor" in its historical battle against the "CSS Virginia" (also known as the Merrimack) at Hampton Roads, Virgina on March 8, 1862. He was temporarily blinded in the battle, and the command of the ship was relinquished to his first officer, Samuel D. Greene, who finished the battle. After the war he was promoted to Rear-Admiral and served as superintendent of the United States Naval Academy.