from The Century Dictionary and Cyclopedia    • n. A system of
pumping the water from deep mines, in which the lift from the
bottom is divided into steps or stages, so that the water is
raised by a series of pumps from level to level, instead of
being forced to the surface in one operation. The stress on the
pipe which discharges the water is less than if the head on one
pump only were the depth of the shaft, and each pump is lighter
than if the total head had to be overcome at once.   Sorry, no
etymologies found.