Novelty toy powered by temperature difference caused by evaporating water. Drinking bird Drinking bird about to dip its beak in the water Classification Heat engines Application Toy, scientific demonstration Fuel source Heat transfer Components Bulbs, tube, axle, support Inventor Miles V. Sullivan / Chinese craftspeople Invented 1945 / much earlier than 1920 Drinking birds, also known as insatiable birdies, dunking birds, drinky birds, water birds, dipping birds,[1][2][3] and "Sippy Chickens" are toy heat engines that mimic the motions of a bird drinking from a water source. They are sometimes incorrectly considered examples of a perpetual motion device.[4] Construction and materials [ edit ] A drinking bird consists of two glass bulbs joined by a glass tube (the bird's neck). The tube extends nearly all the way into the bottom bulb, and attaches to the top bulb but does not extend into it. The space inside the bird contains a fluid, usually colored to make the liquid more visible. The dye might fade when exposed to light, with the rate depending on the dye/color.[5] The fluid is typically dichloromethane (DCM), also known as methylene chloride.[6][7] Earlier versions contained trichlorofluoromethane.[7] Miles V. Sullivan's 1945 patent suggested ether, alcohol, carbon tetrachloride, or chloroform.[8] Air is removed from the apparatus during manufacture, so the space inside the body is filled by vapor evaporated from the fluid.[8] The upper bulb has a "beak" attached which, along with the head, is covered in a felt-like material.[8] The bird is typically decorated with paper eyes, a plastic top hat, and one or more tail feathers. The whole setup pivots on an adjustable crosspiece attached to the neck. Safety [ edit ] Despite the drinking bird's appearance and classification as a toy, there is a potential danger of thin shards of glass should the bulb break. Early models were often filled with highly flammable substances, though the fluid in later versions…