La Force Tranquille, by Romain Matteï, taken in the Zaanse Schans, an area of 18th and 19th century windmills and museums just outside Amsterdam
Windmills, which are used in the great plains of Holland and North Germany to supply the want of falling water, afford another instance of the action of velocity. The sails are driven by air in motion – by wind – Hermann von Helmholtz