Thanks to the help of Professor Rubén Gallo, the Graphic Arts Collection acquired a small peep show viewer, ca. 1865, mounted with 12 miniature albumen silver photographs. The pyramid shaped device has a monocular lens at the front through which one views the photographs. A moveable lid can be raised to let in light. The 12 prints are sewed to a panoramic strip of cloth that is rotated by two copper buttons.
The viewer or visionneuse comes originally from a maison close or brothel in Paris. The images, no more than 3 cm, are of a nude man and woman in various erotic poses, not unlike something you might find today on the internet. Small enough to be held in the palm of your hand, the device could easily be passed secretly from one man to another for their viewing pleasure.
For more about the history of prostitution in 19th century Paris, see the exhibition and catalogue for “Splendor and Misery: Images of Prostitution 1850-1910,” at the Musée d’Orsay. http://www.nytimes.com/2015/09/22/arts/design/splendor-and-misery-images-of-prostitution-captures-a-profession-in-paris-through-artists-eyes.html?_r=0