The day before, the Rebel ram had obliterated two powerful Union warships and was poised to destroy more. That night, the revolutionary-not to say bizarre-Monitor slipped into harbor after hurrying down from New York through fierce gales that almost sank her. These metal monstrosities dueled in the morning, pounding away for hours with little damage to either. Who won is still debated.
One Vermont reporter could hardly find words for Monitor: "It is in fact unlike anything that ever floated on Neptune's bosom." The little vessel became an icon of American industrial ingenuity and strength. She redefined the relationship between men and machines in...