Formerly called also fuzee. The adjunct employed with shells for igniting the bursting charge at the required moment. Time-fuzes, prepared with some composition burning at a known rate, are cut or set to a length proportionate to the time which the shell is destined to occupy in its flight; concussion and percussion fuzes ignite the charge on impact on the object: the former by the dislocation of some of its parts throwing open new passages for its flame, and the latter by the action of various mechanism on its inner priming of detonating composition. They are made either of wood or of metal, and of various form and size according to the kind of ordnance they are intended for. Time-fuzes of special manufacture are also applied to igniting the charges of mines, subaqueous blasts, &c.