Historical Notes: The first iron bridge in the world was constructed between 1777 and 1781 over the Severn River gorge at Coalbrookdale, a center of the iron industry in England. Even while under construction, the bridge became a symbol of the relationship between man and nature in the Industrial Revolution. The bridge's design was the collaborative effort of the Shrewsbury architect Thomas Pritchard and Abraham Darby III, owner of the Darby Ironworks where the bridge was cast. Its single span covered over 100 feet, a distance unimaginable in wood or stone, and allowed for uninhibited barge traffic on the river below.
While living in Paris, Jefferson purchased prints of the iron bridge through a friend in London. He later exhibited one in the Dining Room at Monticello next to a painting of Virginia's Natural Bridge. The most popular print in Jefferson's time, and likely the one he exhibited, was engraved by William Ellis after a watercolor drawing by Michael Angelo Rooker. Darby commissioned Rooker to draw the bridge just after its opening in January 1781. Although better known as a painter, Rooker was skilled in engraving. He exhibited at the Society of Artists and served as scene painter for the Haymarket Theater.
Jefferson discussed iron-bridge construction with Thomas Paine. While living in Philadelphia in 1783, Paine designed an iron bridge. He visited Jefferson in Paris in 1787 on his way to England, and showed him a model of his iron bridge, which he believed could span 400 feet in a single arch-four times that of the Coalbrookdale Bridge.