The PASCO Compression Igniter (or “fire syringe”) illustrates what happens inside the cylinder of a diesel engine. It demonstrates the high temperatures produced during adiabatic compression of air by igniting a small piece of tissue paper inside a thick-wall glass tube. When the piston is rapidly pressed down into the glass tube, the temperature inside the tube rises quickly.

1.  Turn the removable base counterclockwise to unscrew it from the bottom of the igniter. Remove the base and set it aside.
2.  Insert a small piece (~2-3 mm on a side) of tissue paper into the bottom of the glass tube.
3.  Use the loading/cleaning rod to push the piece of tissue paper up into the lower part of the glass tube. Carefully remove the loading/cleaning rod without disturbing the paper.
4.  Replace the removable base by screwing it clockwise into the bottom.  The piece of paper should sit on top of the center of the base.
5.   Insert the piston into the top of the igniter and push it in far enough that the end of the piston lines up with or is slightly below the “Piston Starting Position” label on the outer tube 2.5 cm below the top.
6.  Place the base of the igniter on a sturdy horizontal surface and securely hold the tube with one hand. Make sure that the combustible material in the bottom of the glass tube is visible.
7.  While the audiene watches the piece of combustible material at the bottom of the glass cylinder, with the palm of your hand, quickly slap down on the knob of the piston so the end of the piston goes down into the cylinder rapidly. Slap it down and keep it down!