Metering hypodermic syringe

Claim 1

A PISTOL-TYPE METERING HYPODERMIC SYRINGE COMPRISING A FRAME INCLUDING A STATIONARY HANDLE, A CYLINDER FOR RECEIVING A FLUID REMOVABLY MOUNTED FORWARDLY ON SAID FRAME, A CAP MEMBER CLOSING THE REAR OF SAID CYLINDER, A PISTON RECIPROCABLY POSITIONED IN SAID CYLINDER, AN ELONGATED ROD CONNECTED TO SAID PISTON AND PROJECTING REARWARDLY THROUGH SAID CAP MEMBER, A MEDIAL PORTION OF SAID ROD BEING FORMED WITH TEETH TO AFFORD A RACK, A TRIGGER HANDLE PIVOTALLY CONNECTED TO SAID STATIONARY HANDLE, SPRING MEANS NORMALLY URGING SAID HANDLES APART, SAID TRIGGER HANDLE TERMINATING REARWARDLY IN A SLOTTED SEGMENT, A PAWL MOUNTED IN SAID SLOTTED SEGMENT AND SPRING BIASED INTO NORMAL ENGAGEMENT WITH SAID RACK, AND AN INDEXABLE METERING PLATE ROTATABLY MOUNTED ON A SIDE SURFACE OF SAID SLOTTED SEGMENT IN PARALLEL RELATIONSHIP WITH SAID TRIGGER HANDLE AND IN ALIGNMENT WITH SAID CAP MEMBER, SAID METERING PLATE HAVING FIVE SIDE EDGES OF VARYING LENGTH AND CONFIGURATION, SAID SIDE EDGES ADAPTED TO ABUT SAID CAP MEMBER WHEN SAID TRIGGER HANDLE IS SQUEEZED, SAID METERING PLATE BEING ROTATABLE AROUND AN OFF-CENTER AXIS, WHEREBY EACH OF SAID SIDE EDGES LIMITS THE FORWARD MOTION OF SAID PAWL AND RACK A VARYING PREDETERMINED DISTANCE.