The stopped syringe has come into wide use as a means of transferring small volumes of liquid from one medium to another with accuracy, as in making dilutions and for injections. It is particularly useful with colored solutions which obscure the calibration scale. Such stopped syringes usually deliver only one fixed volume, however. The stop herein described permits accurate delivery of various fractions of the full capacity of a syringe, each setting being reproducible and requiring only a simple, rapid adjustment. This greatly increases the usefulness and versatility of the stopped measuring syringe.
A length of brass or stainless steel tubing 3/16 in. thick and about 4 in. long (hereafter referred to as the "stem") is attached to a yoke clamp which can be tightened around the barrel of the syringe. It is attached to the clamp in such a way that when in place on the syringe it