Flame

Flame has already been defined as a mass of gas raised to incandescence. It will be observed that this definition does not limit flame to such phenomena as are attendant upon combustion; it simply postulates the existence of vapour or gas. Whilst flames may and often do exist under conditions excluding all types of combustion, as for example during the electric discharges through rarefied gases, in the majority of cases flames are the result of rapid oxidation.