John Ernst Worrell Keely was, in his own words, “the greatest humbug of the nineteenth century.” The perpetrator of a long-running and remarkably elaborate pseudoscientific scam, Keely convinced numerous men and women to invest in his Keely Motor Company, an enterprise dedicated to developing practical ways of harnessing an “etheric” force he claimed to have discovered. Over the course of his career, the charlatan-scientist built more than 2,000 machines and gave several headline-grabbing demonstrations in and around Philadelphia using the energy of what he called the “interatomic ether” to shoot bullets, saw wood, and lift weights. After Keely’s death in 1898, his workshop was taken apart and his deception revealed: The machines were powered not by any mysterious, new force, but by simple compressed air routed through the building via hidden ductwork. Despite this revelation, debates between Keely’s supporters (mostly his investors) and detractors continued. The “Etheric Force Machine” pictured, one of only two surviving Keely inventions, is part of the otherwise authentic collection of historic machine tools held by the American Precision Museum in Windsor, Vermont. In 2008, the museum received an NEH grant to plan a new permanent exhibition.