Hyman Fire Piston (STE 12117)

The Hyman Fire Piston demonstrates the rise in temperature when a fixed mass of gas is compressed.  A portion of tinder supported inside a transparent cylinder is ignited when the contained air is compressed by a hand operated pistion.

Suitable tinder is provided, though almost any organic material withh do if dry enough e.g. cotton, charcoal or tissue paper.

You can also demostrate the need for oxygen to support combustion by attempting to re-ignite a piece of tender  it will only occur if the pistion is completely removed from the cylinder and a supply of fresh air introduced.  A cloud can be formed in the cylinder by having the compressed air inside it, allowing a sudden decompresion.  The reduction in pressure lowers the temperature and immediately condenses the water vapour inside the cylinder.  This can be seen quite easily, but is often mistaken for smoke given the combustion has already taken place.