To surely store even a slight amount of medium and discharge it without substantially leaving it, by singly manipulating a delivery actuator at a position variably manipulating the medium of the volume measured and allotted, which is held in a needle-shaped medium reservoir.

A reservoir 8 for a medium is a needle-shaped fine tube and arranged in the inside of a reservoir 9. And a chamber 12 holds a liquid in the reservoir 9 and has a circular space with a large volume. A tubular shell 14 is made of a transparent material and the reservoir 8 can be visually confirmed from the outside. A piston is provided with a diaphragm 20 having a circular disk shape, made of a flexible material, at the center. When manually pushing the lever 6, the piston 16 moves to the reservoir 8 and the front end 19 for opening a hole and pressurizes the fluid in the chamber 12. And further, when the front end 19 pierces the diaphragm 20, the mixture of the fluid and the medium is discharged from a medium orifice 30 through the opening 17 and the reservoir outlet 18 and the medium is completely discharged.