Hydraulics
Hydraulics, the branch of engineering that deals with water and other liquids. Hydraulics makes use of the principles of hydromechanics, a field of physics.
Hydraulic engineers build dams, spillways, irrigation structures, aqueducts, canals, flood-control dikes, and piers. Hydraulic engineering principles are used in the construction of oil and gas pipelines and storage tanks. Placer mining of gold is a hydraulic process. Hydraulics research is concerned with ways to improve nozzles and valves; the hulls and propellers of boats; and pumps, turbines, and other hydraulic machinery.