Abstract: An apparatus for the measurement of liquid quantity, comprising a frame (12) with a chamber space (13) inside it, an inlet duct (8) in the top part of the frame to pass a liquid into the chamber space (13), an outlet duct (11) in the bottom part of the frame to pass the liquid out of the chamber space (13) and elements (1, 2) placed in the chamber space (13) to form a weir container, said elements comprising a wall (2) and at least one orifice (1) formed in the wall, through which orifice (1) the liquid is passed out into the outlet duct (11), and means (3) for measuring the level of the liquid in the chamber space (13). The apparatus comprises means (10) for directing the liquid entering the chamber via the inlet duct (8) into at least two sub-flows (14, 15) and for directing these sub-flows from different directions to a point near the orifice (1) in the wall so that when the sub-flows (14, 15) meet again, they substantially damp the flow.