Potain's Aspirator This is an aspirator designed by Potain. It is composed of a metal air pump, a metal and brass plunger, and a double stopcock, all of which are detachable. The plunger is inscribed with the numbers 1 and 2. The maker is unknown. Typically, it is part of a set that includes a side branch trocar and stopcock, three needles, and two trocars with obturators. To operate it, the stopcock on the side of the trocar is opened and the one on the opposite side is closed while the piston is being pulled, a negative pressure is created in the vessel. When the pump is closed and the trocar is removed from the cannula, the stopcock on the side of the cannula is opened. This causes the vacuum in the bottle to draw blood, pus, or air from the pleural cavity. The septic fluid only passes between the body, the rubber hoses, and the vessel, thereby minimising the risk of further infection. 1925-1975