From The Art and Popular Culture Encyclopedia
"As old as the tension between art music and vulgar music is, it became radical only in high capitalism. In earlier epochs, art music was able to regenerate its material from time to time and enlarge its sphere by recourse to vulgar music. This is seen in medieval polyphony, which drew upon folk songs for its cantus firmi, and also in Mozart, when he combined peep-show cosmology with opera seria and Singspiel."--"On the Social Situation of Music" (1932) by Theodor Adorno
A peep show or peepshow is an exhibition of pictures or objects viewed through a small hole or magnifying glass. This may or may not be a sex show, although the latter kind has eventually become the most common usage of the term since the advent of cinema and television, which destroyed various kinds of entertainment provided by wandering showmen.
Peep shows , also known as peep box or raree show ("rarity show") trace back to ancient times (15th century in Europe, by Leon Battista Alberti) and are known in various cultures. A peep show could be a wooden box with a hole or several holes, containing a set of pictures which the show-man could set into a viewing position by pulling a corresponding string. The boxes were often decorated inside to resemble theatrical scenes. The show was accompanied by spoken recitation that explained or dramatized what was happening inside.
19th century Chinese peep shows were known by many names including la yang p'ien ("pulling foreign picture cards"). Sometimes the showman would perform for a crowd with puppets or pictures outside the box and then charge people extra to look through the holes. In Syria, Lebanon and Ottoman Palestine a form of peep show called sanduk al-ajayib ("wonder box") existed, which the storyteller carried on his back. The box had six holes through which people could see scenes backlit by a central candle. Sanduk al-ajayib stories were about contemporary figures and events, or showed scenes of heaven and hell. Other common subjects in peep shows throughout the world have been exotic views and animals, scenes of classical drama or masques, court ceremonies, surprise transformations (e.g., of an angel into a devil) and of course, lewd pictures.
Raree shows were precursors of toy theatres, with movable scenes and paper figurines, popular in the 19th century.