Abstract: A system for measuring components of an ambient fluid such as air. A syringe includes an intake fitting which provides sealed fluid coupling to a chromatographic intake tube. The syringe includes exhaust ports near the intake end of the syringe. The ports exhaust fluid in the cylinder directly into the atmosphere without passing the exhaust fluid through the indicator tube. The exhaust ports are shaped and located to be sealed by the thumb and forefinger of an operator's hand. In operation, the operator covers the exhaust ports on the syringe with his fingers. He then pulls the plunger to draw fluid into the syringe. He then withdraws his fingers to open the vent holes and expells fluid through the vent holes by depressing the plunger. These steps are repeated until a preselected volume of fluid has been drawn syringe-ward through the analysis tube. The tube is then observed.