A novel windmill or revolving wheel can be made by placing a light wheel so it will turn freely on the end of a post, and placing four small sailing boats at equal points on the rim of the wheel. It makes no difference which way the wind blows, the wheel will revolve in one direction. In Fig. 1 the direction of the wind is shown by the arrows, and how the sails catch the wind and cause the wheel to revolve. Figure 2 shows how the wheel will appear when complete. This device makes an attractive advertising sign. An Unusual Type of Windmill

Illustration: An Unusual Type of Windmill