Abstract: A measuring reservoir for measuring the volume of the second component of a two-component mixture by the given volume of the first component and the given ratio of the mixture components is described. The reservoir has a housing of transparent material with measuring scales marked on the outside. The first scale is for the measurement of the volume of the first component, the second scale is a ratio scale on which there are marks corresponding to the ratio of the volumes of the components. One of the scales is stationary and marked on the outside of the housing, the other scale is movable along the stationary scale. A cursor is coupled to the movable scale in a cantilever manner. The cursor is shaped as a plank or rod oriented along the side surface of the housing on which a level curve of the second component is marked.