I just shared this book on the PC book forum. It's a rollicking ride of the story of a charlatan, huckster "doctor" who developed this scam in the early 1900's!
Great, rollicking read, this.
Amazon.com: Charlatan: America's Most Dangerous Huckster, the Man Who Pursued Him, and the Age of Flimflam eBook: Pope Brock: Kindle Store