Orrerries are mechanical models of the solar system, designed to show the relative position and movement of the planets. They have been produced since antiquity but the name derives from the first modern device, made in England in the early eighteenth century—a copy of which was owned by the Earl of Orrery. Princeton’s is the first American example, completed in 1770 by the Philadelphia clockmaker and astronomer David Rittenhouse. Rittenhouse’s advanced design was thought to portend America’s scientific promise. Such was its significance that its removal from Philadelphia caused an uproar. The provost of the University of Pennsylvania objected that its maker could, as he said, “think so little of his noble invention, as to consent to let it go to a village.” Despite the device’s renown, the orrery’s relevance diminished over time, and in 1948 this example was discovered in a shipping box, where it had remained since its return from the 1893 Chicago World’s Fair.