The Crookes Radiometer is a classic piece of vintage science equipment and a fun, visual learning tool. It also happens to be a beautiful decorative piece, and adds a touch of elegance to any setting. Its basic form is a glass bulb with a base; inside the bulb is a frictionless vertical shaft with four delicate diamond-shaped vanes, each with a dark side and a light side. When light shines on the vanes they move, turning the shaft (some versions can spin up to 1000 revolutions a minute). The cau