The seemingly bizarre images drawn on cardboard are actually projections of "normal" images (one is a human figure, the other a picture of dice). When the drawing is placed in front of a suitably distorted mirror, the reflected image is restored to its normal shape. Such toys, called anamorphoses, were widely diffused in the seventeenth century, in keeping with the contemporary taste for the Baroque. Anamorphoses were made famous by the productions of Jean-François Niceron.