The device here illustrated I have found so easy to make and so efficient in application that I trust it may be of value to others. The parts consist of a glass tube (a), a medium hard, thick-walled rubber tube (c) with small lumen (d) for a piston, and a soft thick-walled rubber tube (e) with small lumen (f) for connecting the glass tube with the pipette. The piston tube (c) may be a solid medium hard rubber cord if obtainable, and the connecting tube (e) any soft rubber tube, but I have found the parts described very satisfactory. The piston tube here used is abdominal supporter tubing, and the connecting tube is the soft rubber tubing used for the flexible connection of antitoxin syringes. The piston tube should fit the glass tube very loosely before the end of the latter is constricted (b).
To make, cut the parts the