Napalm is jellied gasoline. Its name is an acronym of naphthenic and palmitic acids, which are used in its manufacture. While used in World War II and the Korean War, napalm became notorious in Vietnam where it was used in three capacities. Possibly its most visual use was being dropped from aircraft in large canisters which tumbled sluggishly to earth. Exploding on impact, it engulfed large areas in flame, sucking up all the oxygen and emitting intense heat, thick black smoke, and a smell which no one exposed to it will ever forget. Dropping napalm from high-speed jet aircraft was not very accurate, resulting in numerous instances of "friendly" (Allied) and/or civilian casualties. A second use of napalm was in flame throwersóby both U.S.-ARVN and Vietcong-North Vietnamese Army forcesówhich were very successful in clearing bunkers. If the flames could not be directed to penetrate the bunker, they could bathe the bunker in fire, consuming all the oxygen and suffocating those inside. Flamethrowers also were used in destroying "enemy" villages. Napalm was used in base camp and fire base perimeter defense. Barrels of napalm would be buried under concertina wire (coils of barbed wire standing two-three feel high and stretched around the perimeter). As troops massed to breach the wire, the barrels would be detonated, incinerating anyone in the immediate area. A frightening, effective weapon, napalm's properties are such that it clings to whatever it touches. Smothering it is the only effective way to put it out. Trying to wipe it off only spreads it around, expanding the burn area. The swift consumption of oxygen can cause suffocation, and the intense heat can produce severe burns without actual contact. The noise, smoke, and smell are terrifying in themselves.