It shall be unlawful for any person to fire, discharge or set off any gun, rifle, pistol, revolver or other firearms, air rifle, cannon, torpedo, squib or other dangerous weapon of any character within the city without a written permit from the chief of police and director of safety; provided, that this section shall not apply to members of any military company when engaged in drilling or target practice under the command or direction of any officer thereof, or to the use of firearms in the lawful defense of person or property, or to the use of firearms by members of the police department in the lawful discharge of their duty. (1961 Supp., § 12.49)