Flywheel
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A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, assuming the flywheel's moment of inertia is constant then the stored (rotational) energy is directly associated with the square of its rotational speed.
Trevithick's 1802 steam locomotive, which used a flywheel to evenly distribute the power of its single cylinder
A mass-produced flywheel
A Landini tractor with exposed flywheel
Noria
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A noria is a hydropowered scoop wheel used to lift water into a small aqueduct, either for the purpose of irrigation or to supply water to cities and villages.
Remains of the medieval Albolafia noria in Cordoba, Spain (the wheel itself was reconstructed in the 20th century)
Noria in Tomar, Portugal. Paired ceramic pots along the wheel collect the water.
Close-up of the previous