Thermodynamic Kaleidoscope

The Thermodynamic Kaleidoscope projects a kaleidoscopic moving image onto a wall or ceiling.
Its peculiarity is that it doesn’t use any type of engine to generate the movement of the image, and instead it uses the residual energy of a single element. An incandescent lamp produces light, but also heat, and this is used in two ways: the hot airflow on the inside of the device rotates the mirror system (which is the basis of the kaleidoscopic effect), and also moves the coloured particles floating in a liquid. The containing vessel has a spherical shape which makes the projector lens system really simple: it is completed with a single biconvex lens (a recycled magnifying glass).