Detonation

The instantaneous conversion of an explosive into gas; a term applied to the phenomena attending the explosion of certain substances, such as nitro-glycerine , chloride of nitrogen , iodide of nitrogen , gun-cotton , the picrates , etc. Detonation, or explosion of the first order, is distinguished from ordinary explosion, or explosion of the second order, by the different way in which the explosion is propagated. Ordinary explosion proceeds by inflammation, being nothing more than a rapid combustion. Detonation is propagated by vibration. A detonating agent is a substance used to produce the initial vibration , or “impulse of explosion.” The exploder, or cap, used for this purpose is usually primed with fulminate of mercury, a substance having a wide range in bringing about detonation in the high explosives.