Abstract: A device for measuring the liquid portion of a two-phase flow of gas and liquid in conveying a liquid by means of a gas comprises a tubular housing (1) and a turbine wheel (2) with axial throw-flow rotatably mounted therein, said turbine wheel being provided with at least one magnetic element (8) at a radially outward portion thereof, said element having limited extent axially and peripherally of said turbine wheel (2). The device furthermore comprises magnetic pick-up means (9) adapted to emit output signals responsive to the rotary speed of the turbine wheel (2), said wheel being mounted for axial movement in the direction of flow from an initial position against a biassing force.