From the 16th century through the industrial revolution to the end of the 19th century, mechanical power transmission was the norm. The oldest long-distance power transmission technology involved systems of push-rods or jerker lines ("stängenkunst" or "feldstängen") connecting waterwheels to distant mine-drainage and brine-well pumps. A surviving example from 1780 exists at Bad Kösen that transmits power approximately 200 meters from a waterwheel to a salt well, and from there, an additional 150 meters to a brine evaporator. This technology survived into the 21st century in a handful of oilfields in the US, transmitting power from a central pumping engine to the numerous pump-jacks in the oil field.