Discussion

This demonstration illustrates the principle behind a grain elevator explosion. Grain dust, like lycopodium powder, is not especially flammable, but when grain is dumped into a grain silo, some of the finer dust particles can remain suspended in air surrounded by oxygen. This mixture can be ignited by a spark, resulting in an explosion.

Lycopodium powder is a fine yellow powder derived from the spores of lycopodium clavatum (stag's horn club moss).

Narration

Lycopodium powder is placed in the top of a funnel mounted inside a large can. A lighted candle is also placed in the can. The cover of the can is firmly pressed into place. Air forced into the funnel causes the powder to disperse within the can and to be ignited.