A syringe cylinder 12 includes a groove 32 formed in an inner peripheral surface thereof and extending over a predetermined length from an opening end 30 thereof. Even with the intermediate sliding stopper 14 located at a position where the groove 32 is formed, the pressure inside the syringe cylinder 12 can be reduced. Thus, during vacuum tapping, the intermediate sliding stopper 14 can be held in the vicinity of the opening end 30 of the syringe cylinder 12. Consequently, the intermediate sliding stopper 14 can be inserted into the syringe cylinder 12 in a correct posture and reliably moved to a predetermined position in the syringe cylinder 12.