Some machines require both power and water. A household example is the washing machine. By using a small water wheel, the water that is needed to wash the clothes can also serve to power the machine. Washing machines powered by water from the town mains were quite common in the early decades of the twentieth century. The pictures show a portable American model called the "Washerette" (see it in operation in this video). It was connected to a faucet and put on the sink or bathtub so that exhaust water could be easily captured. The images were found at Smokstak.