The public spaces and buildings of the United States are home to many thousands of timepieces-bells, time balls, and clock faces-that tower over urban streets, peek out from lobbies, and gleam in store windows. And in the streets and squares beneath them, men, women, and children wear wristwatches of all kinds. Americans have decorated their homes with clocks and included them in their poetry, sermons, stories, and songs. And as political instruments,...