When Paine arrived in Philadelphia from England in 1774, the city was thriving as America’s largest port. But the seasonal dangers of the rivers dividing the region were becoming an obstacle to the city’s continued growth. Philadelphia needed a practical connection between the rich grain of Pennsylvania’s backcountry farms and its port on the Delaware. The iron bridge was Paine’s solution. The bridge was part of Paine’s answer to the central political challenge of the new nation: how to sustain a republic as large and as geographically fragmented as the United States. The iron construction was Paine’s brilliant response to the age-old challenge of bridge technology: how to build a structure strong enough to withstand the constant battering of water, ice, and wind. The convergence of political and technological design in Paine’s plan was Enlightenment genius. And Paine drew other giants of the period as patrons: Benjamin Franklin, George Washington, Thomas Jefferson, and for a time his great ideological opponent, Edmund Burke. Paine’s dream ultimately was a casualty of the vicious political crosscurrents of revolution and the American penchant for bridges of cheap, plentiful wood. But his innovative iron design became the model for bridge construction in Britain as it led the world into the industrial revolution.

Edward G. Gray is a professor of history at Florida State University and the author of several important works in early American history.