A hydraulic power network is a system of interconnected pipes carrying pressurized liquid used to transmit mechanical power from a power source, like a pump, to hydraulic equipment like lifts or motors. The system is analogous to an electrical grid transmitting power from a generating station to end-users. Only a few hydraulic power transmission networks are still in use; modern hydraulic equipment has a pump built into the machine. In the late 19th century, a hydraulic network might have been used in a factory, with a central steam engine or water turbine driving a pump and a system of high-pressure pipes transmitting power to various machines.
The pumping station and hydraulic accumulator at Bristol Docks
Machell Street hydraulic pumping station in Hull, showing the water settling tank on the roof
The preserved pumping equipment in Wapping pumping station, which was owned by the London Hydraulic Power Company
The external hydraulic accumulator at Bristol Harbour
Hydraulics is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which concerns gases. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on applied engineering using the properties of fluids. In its fluid power applications, hydraulics is used for the generation, control, and transmission of power by the use of pressurized liquids. Hydraulic topics range through some parts of science and most of engineering modules, and cover concepts such as pipe flow, dam design, fluidics and fluid control circuitry. The principles of hydraulics are in use naturally in the human body within the vascular system and erectile tissue.
Illustration of hydraulic and hydrostatic, from the "Table of Hydraulics and Hydrostatics", from Cyclopædia, or an Universal Dictionary of Arts and Sciences, edited by Ephraim Chambers, 1728, Vol. 1
Waterwheels
Moat and gardens at Sigiriya
Aqueduct of Segovia, a 1st-century AD masterpiece