With P. T. Barnum's purchase of the American museum in 1840, freak shows became an organized and profitable institution that systematically used juxtaposition, innovative advertising, and questions of truth and humbug to entice audiences. Along with “scientifically” sanctioned pamphlets and cartes de visite, exhibits such as wild savages from around the world, human-animal hybrids, hermaphrodites, and armless and legless wonders played with the boundaries between self and other. Audiences could gaze safely without compunction about the displayed body as long as these distinctions were maintained within the confines of the show. But as social anxieties about difference intensified in the first few decades of the 20th century, a greater need to solidify the boundaries between black and white, male and female, and abled and disabled made this type of entertainment more disturbing and, at times, even dangerous. These concerns marked the beginning of the end for freak shows. By the 1920s, their popularity was not only threatened by changing attitudes in medical science and the rise of the film industry, but also by the aftermath of World War I.