A dispensing apparatus for measuring a quantity of material to be dispensed, the dispensing apparatus having: a dispensing unit for dispensing at least part of the material; a reservoir containing the material to be dispensed; tubes between the reservoir and the dispensing unit, the tubes carrying material into and from the reservoir; a scale under the reservoir, the scale being for connection to a processor for processing electronic signals from the scale and for converting the signals into a weight measurement; the dispensing apparatus being characterized in that: the tubes are inserted into the reservoir through a flexible membrane fixed to a mouth of the reservoir; or the tubes comprise plunged tubes inserted into the reservoir through a reservoir cap, wherein: a cylindrical smooth dry bearing is attached firmly to the reservoir cap, the cylindrical smooth dry bearing in the reservoir cap being free to slide vertically along and in rotation around a tube holder located between the reservoir and the dispensing unit and rigidly holding the plunged tubes; or the dispensing apparatus further includes a tube holder located between the reservoir and the dispensing unit, rigid tubes tied to the tube holder, and flexible tube sections extending between the reservoir and the rigid tubes, wherein first extremities of the flexible tube sections are connected to the plunged tubes, and second extremities of the flexible tube sections are connected to first extremities of the rigid tubes tied to the tube holder. a dispensing unit for dispensing at least part of the material; a reservoir containing the material to be dispensed; tubes between the reservoir and the dispensing unit, the tubes carrying material into and from the reservoir; a scale under the reservoir, the scale being for connection to a processor for processing electronic signals from the scale and for converting the signals into a weight measurement; the dispensing apparatus being characterized in that: the tubes are inserted into the reservoir through a flexible membrane fixed to a mouth of the reservoir; or the tubes comprise plunged tubes inserted into the reservoir through a reservoir cap, wherein: a cylindrical smooth dry bearing is attached firmly to the reservoir cap, the cylindrical smooth dry bearing in the reservoir cap being free to slide vertically along and in rotation around a tube holder located between the reservoir and the dispensing unit and rigidly holding the plunged tubes; or the dispensing apparatus further includes a tube holder located between the reservoir and the dispensing unit, rigid tubes tied to the tube holder, and flexible tube sections extending between the reservoir and the rigid tubes, wherein first extremities of the flexible tube sections are connected to the plunged tubes, and second extremities of the flexible tube sections are connected to first extremities of the rigid tubes tied to the tube holder. the tubes are inserted into the reservoir through a flexible membrane fixed to a mouth of the reservoir; or the tubes comprise plunged tubes inserted into the reservoir through a reservoir cap, wherein: a cylindrical smooth dry bearing is attached firmly to the reservoir cap, the cylindrical smooth dry bearing in the reservoir cap being free to slide vertically along and in rotation around a tube holder located between the reservoir and the dispensing unit and rigidly holding the plunged tubes; or the dispensing apparatus further includes a tube holder located between the reservoir and the dispensing unit, rigid tubes tied to the tube holder, and flexible tube sections extending between the reservoir and the rigid tubes, wherein first extremities of the flexible tube sections are connected to the plunged tubes, and second extremities of the flexible tube sections are connected to first extremities of the rigid tubes tied to the tube holder. a cylindrical smooth dry bearing is attached firmly to the reservoir cap, the cylindrical smooth dry bearing in the reservoir cap being free to slide vertically along and in rotation around a tube holder located between the reservoir and the dispensing unit and rigidly holding the plunged tubes; or the dispensing apparatus further includes a tube holder located between the reservoir and the dispensing unit, rigid tubes tied to the tube holder, and flexible tube sections extending between the reservoir and the rigid tubes, wherein first extremities of the flexible tube sections are connected to the plunged tubes, and second extremities of the flexible tube sections are connected to first extremities of the rigid tubes tied to the tube holder.