A device for mixing powder of the like with a liquid, the device including both a dispersion tube having its bottom portion open and designed to be in the liquid and having a delivery orifice for powder or the like in its top portion, and a mixer located in the dispersion tube and including a first rotary stirrer disposed in the vicinity of the bottom end of the dispersion tube and suitable for creating a first downward stream in the dispersion tube. The mixer further includes a second rotary stirrer disposed between the delivery orifice for powder or the like and the first rotary stirrer, and suitable for creating a second downward stream in the dispersion tube.