Windmills. Medieval Europeans who did not live near rivers or streams capable of turning waterwheels harnessed the wind to power their mills. In the Low Countries, for example, the average elevation is only a few feet above sea level (and many areas where land was reclaimed are actually at mean sea level—that is, below storm-surge levels). While water is plentiful there, it is not suited to powering mills. They do have steady winds coming off the North Sea, however, and the windmill became their principal means of power. Windmills began to appear in Europe during the 1180s, and seem to have come from Asia Minor. The earliest known windmills were horizontal mills used by the mid tenth century in Anatolia, a high, arid region in modern Turkey, which, like the Low Countries, has little water-power potential, but a...