title: The rod of Aesculapios: John Haygarth (1740-1827) and Perkins' metallic tractors.
abstract: James Gillray's cartoon Metallic Tractors, published in 1801, portrays Benjamin Perkins treating a boil on the nose of an alcoholic John Bull with a pair of metallic tractors. The tractors had been invented by his father, Elisha Perkins of Connecticut, and were supposed to relieve pain and other symptoms through the agency of animal magnetism. The tractors were revealed as nothing more than an expensive sham by Dr John Haygarth in Bath, who showed that wooden tractors were equally effective. Thus, he was one of the first to use a placebo in a single-blind clinical trial.
authors.affiliation: Wellcome Centre for the History of Medicine, University College London, UK. ucgacbo@ucl.ac.uk
authors.forename: Christopher
authors.initials: C
authors.lastname: Booth
mesh_terms: D002986:Clinical Trials as Topic / Q000266:history; D000529:Complementary Therapies / Q000266:history*; D004739:England; D049671:History, 18th Century; D049672:History, 19th Century; D006801:Humans; D011781:Quackery / Q000266:history*; D016037:Single-Blind Method