Harden ceramic Star hand fire extinguisher grenade, circa 1880s. Hermetically sealed and filled with a chemical fluid, the contents of the grenade, according to The Harden handbook, .."when thrown upon or into a fire, vaporize immediately into immense volumes of fire extinguishing gas in which combustion can not possibly exist." Unfortunately, carbon tetrachloride was the chemical of choice as it vaporized immediately ? therefore dangerous to humans (and all animals) as it is easily absorbed both through the lungs and the skin.