SEC. 23. No person or persons shall fire any gun, pistol, or rifle, or other description of fire-arms, or discharge any air-gun whatever within the fire limits of the city, or in any corral, yard or street within said fire limits, under a penalty of five dollars for the first offence; ten dollars for the second offence, and for the third offence, not more than fifty dollars and imprisonment at the discretion of the Mayor, not exceeding ten days.