Carbide lamp

For over a century, calcium carbide has been reacted with water to produce calcium hydoxide and acetylene, a flammable gas that can burn with a bright flame.  Lamps, such as those used in mines, have used these reactions to produce illumination, see: http://en.wikipedia.org/wiki/Carbide_lamp.  Acetylene produced from calcium carbide has been used in chemistry demonstrations, such as those demonstrating explosive ranges. Acetylene can burn quietly at high concentrations relative to oxygen, but can explode at low concentrations relative to oxygen.  Because exposions can occur, I will not discuss these demonstrations in more depth.