Perception is fragile and easily manipulated. A painting or drawing that is flipped, flopped or stared at long enough can somehow be transformed from one image to another.In this engaging collection of paintings, drawings, cartoons, masks, toys and other work, there are optical illusions from the Renaissance, Enlightenment-era political cartoons and Victorian toys that start off as one thing and end up as another. Sometimes these mutations were made for fun, sometimes for profit or to score a political point, but the results are always an intriguing pleasure to view.Even the most jaded readers will find their frowns turned upside down after they pick up this delightful volume.