A dropper machine for dropping a metered amount of a substance in a plurality of receptacles, comprising: - a support structure, - a reservoir containing the substance to be dropped, supported by said structure, - a plurality of cylinder and piston type metering devices with an inlet positioned below the level of the substance to be poured into the reservoir and an outlet communicating with a respective dropper nozzle, - at least one drive unit (100A, 100B) arranged to simultaneously drive the pistons of said metering devices according to a forward and backward motion between a start position and an end position where the displacement of the pistons from the end position to the start position causes the suction of the substance from the reservoir through said inlet opening to the cylinder of the metering devices and the displacement of the pistons from the start position to the end position is adapted to cause the delivery of the substance through the respective nozzles, characterized in that to each of said metering devices is associated a respective actuator device cooperating with the piston of said metering device, said actuator device being operable individually to inhibit the delivery of the substance through said nozzle when the drive unit (100A, 100B) is actuated to cause the displacement of the pistons of the metering devices associated therewith between the start position and the end position, wherein said actuator device is adapted to cause the displacement of the piston of the respective metering device between a deactivation position of the delivery and an activation position of the delivery through the respective nozzle, where, in said deactivation position, the axial displacement of the piston from the start position to the end position caused by the drive unit (100A, 100B) causes the expulsion of the substance contained in said cylinder through said inlet opening inside the reservoir while, in said dropping activation position, said axial displacement of the piston from the start position to the end position caused by the drive unit causes the dosage of the substance through said nozzle. - a support structure, - a reservoir containing the substance to be dropped, supported by said structure, - a plurality of cylinder and piston type metering devices with an inlet positioned below the level of the substance to be poured into the reservoir and an outlet communicating with a respective dropper nozzle, - at least one drive unit (100A, 100B) arranged to simultaneously drive the pistons of said metering devices according to a forward and backward motion between a start position and an end position where the displacement of the pistons from the end position to the start position causes the suction of the substance from the reservoir through said inlet opening to the cylinder of the metering devices and the displacement of the pistons from the start position to the end position is adapted to cause the delivery of the substance through the respective nozzles, characterized in that to each of said metering devices is associated a respective actuator device cooperating with the piston of said metering device, said actuator device being operable individually to inhibit the delivery of the substance through said nozzle when the drive unit (100A, 100B) is actuated to cause the displacement of the pistons of the metering devices associated therewith between the start position and the end position, wherein said actuator device is adapted to cause the displacement of the piston of the respective metering device between a deactivation position of the delivery and an activation position of the delivery through the respective nozzle, where, in said deactivation position, the axial displacement of the piston from the start position to the end position caused by the drive unit (100A, 100B) causes the expulsion of the substance contained in said cylinder through said inlet opening inside the reservoir while, in said dropping activation position, said axial displacement of the piston from the start position to the end position caused by the drive unit causes the dosage of the substance through said nozzle.