Wham-O Magic Window http://main.physicsfunstore.com/p/main.html Popular 1970s toy with immiscible sand like substances interacting under gravity to create images that evoke seascapes and mountains. Unlike most shifting sand devices available today, the Magic Window did not contain any liquid- all the interesting behavior results from the physics of granular materials, specifically interactions due to different sizes and shapes (jagged like salt or round like glass beads) of the grains comprising