Chromatropes

magic lanternsA group of art history students have organized a visit to the Graphic Arts Collection on Friday to see our collection of magic lanterns. With help from the Cotsen Collection, we have arranged quite an assortment of lanterns and lantern slides.
chromotrope1In particular, we have a number of slipping slides, artificial fireworks, kaleidoscopes, and [seen here] chromatrope slides. These have a second strip of painted glass over a fixed one and use a rack and pinion mechanism to create a circular motion. The lantern operator would slowly turn the crank and make planets move, ships sail, and a variety of objects appear or disappear. Here’s one example (note the image would be laterally reversed when projected through the lantern’s lens):

chromotrope

 

See also this post about the Cotsen Childrens Library’s collection: https://blogs.princeton.edu/cotsen/2015/01/mechanical-magic-patterns/