The set is titled Detector Casey's Fire Safety Mysteries . Eventually, the friction results in an increase in temperature sufficient to reach the kindling temperature or ignition temperature of the combustible material. Until about 1827, the spark created when flint was struck against iron pyrites or steel or another piece of flint was the major way to start a fire in western cultures. About 1827, the use of matches, a friction method, came into use. Fire can be started by using a lens to focus sunlight on combustible material.
Many cultures use dried animal dung as a fuel.
LPG means liquid propane gas. It is made up of carbon and hydrogen. Propane is under pressure so that it becomes a liquid and is stored in a pressurized tank. Methane is a major component of coal gas. Methane, like propane, consists of carbon and hydrogen.