<P> Snake oil is a fraudulent liniment without snake extract . Currently, it has come to refer to any product with questionable or unverifiable quality or benefit . By extension, a snake oil salesman is someone who knowingly sells fraudulent goods or who is a fraud, quack, or charlatan . </P> <P> The use of snake oil long predates the 19th century . In Europe, viper oil had been commonly recommended for many afflictions, including the ones for which rattlesnake oil was subsequently favored (e.g., rheumatism and skin diseases). In China, oil made from Chinese water snake (Enhydris chinensis) fat is a traditional liniment used for treating joint pain . Chinese water - snake oil contains 20 percent eicosapentaenoic acid (EPA), which has strong analgetic and anti-inflammatory properties . </P> <P> Chinese laborers on railroad gangs involved in building the First Transcontinental Railroad first gave snake oil, a traditional folk remedy in Traditional Chinese Medicine, to treat joint pain such as arthritis and bursitis to their fellow workers . When rubbed on the skin at the painful site, snake oil was claimed to bring relief . This claim was ridiculed by rival medicine salesmen, and in time, snake oil became a generic name for many compounds marketed as panaceas or miraculous remedies whose ingredients were usually secret, unidentified, or mischaracterized and mostly inert or ineffective . </P> <P> Patent medicines originated in England, where a patent was granted to Richard Stoughton's elixir in 1712 . Since there was no federal regulation in the United States concerning safety and effectiveness of drugs until the 1906 Food and Drugs Act and various medicine salesmen or manufacturers seldom had enough skills in analytical chemistry to analyze the contents of snake oil, it became the archetype of hoax . </P>

Where does the term snake oil come from
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