treble barrel pump

A pump having three barrels connected with a common suction-pipe. The pistons are operated by a three-throw crank, the cranks being set at angles of 120°, so that each piston is always at a different part of the stroke from either of the others, and a continuous flow produced. treble-block, s. tree trěb-lět, s. (TRIBLET.) trè trěb-ly, adv. [Eng. treb (le), a.; -ly.] In a treble manner; in a threefold manner, degree, or quantity; triply.