The structure of the ancient popular lanterns in China

In a square or round paper lantern, insert a wire as a vertical axis, the shaft above the installation of an impeller, the center of the shaft installed two cross thin wire, in each end of the wire glued to the people, horses and other paper cuttings. When the lantern candle is lit, the hot air rises, forming air currents, which pushes the impeller to rotate, so the paper cutouts rotate with the axle. Their shadows are projected onto the paper cover of the lantern.