Perkins Patent Tractors

Perkins Patent Tractors were a medical device invented by the American physician Elisha Perkins, who lived from 1741 to 1799, consisting of two pointed metal rods about three inches long. Although the rods were made of ordinary steel and brass, Perkins claimed they were formed from unusual metal alloys and that drawing them across the skin could cure inflammation, rheumatism, and facial pain by removing a supposed noxious electrical fluid believed to underlie suffering. The Connecticut Medical Society expelled Perkins for practicing what it called delusive quackery, but the tractors nonetheless found considerable support: three American medical faculties endorsed the method, twelve surgeons at the royal hospital in Copenhagen adopted it, and George Washington owned a set. Perkins claimed to have cured five thousand cases, backed by testimonials from eight professors, forty physicians, and thirty clergymen. His son Benjamin brought the tractors to London, where a charitable institution was founded to supply them to the poor, but after Elisha Perkins died of yellow fever in 1799, the physician John Haygarth ran an early placebo-controlled study using wooden replicas of the tractors that worked just as well, showing how much of the tractors apparent effect came from the power of suggestion. The tractors popularity declined after Benjamin Perkins died in 1810.