An 18th century quack "De Wonderdokter Fop" with Dutch text, illustrated by Hermann van der Moolen. "Een man die bang voor pookken was, Wou zijn gevaccineerd; Ik 'entte hem met 't braadspit in, En heb hem erg bezeerd." (A man who was afraid of poker, Wou were vaccinated; I caught him with a bacon, and hurt him very much.) Quackery is the promotion of unproven or fraudulent medical practices. Random House Dictionary describes a "quack" as a "fraudulent or ignorant pretender to medical skill" or "a person who pretends, professionally or publicly, to have skill, knowledge, or qualifications he or she does not possess; a charlatan".