Hoaxers & Their Victims

``Everything is mortal except human gullibility,'' a hoaxer once said; this entertaining volume bears it out. Here are famous hoaxes surveyed, from Naked Came the Stranger , Clifford Irving's biography of Howard Hughes to the ``discovery'' of Hitler's diaries. Yapp examines the lives of some of the most famous practitioners of the art, like Charles Dawson, who found the so-called Piltdown Man in 1912; and Hans van Meegeren, the famed art forger who sold several of his ``Vermeers'' and ``de Hooghs'' to Hermann Goring. Hoaxes are undertaken, Yapp believes, for fame, money, fun, revenge or satire; their perpetrators combine deceit and conceit. The victims often persist in their delusions, even after the hoaxes have been exposed. A photo insert includes two purported shots of fairies dancing on an English lawn--they look suspiciously like paper dolls. (Oct.)