It is unlawful for any person to place or keep, or allow to be placed or kept, any pot, jar, or box plants or flowers in the window sill of any building touching or coming near to the street line of any public street in the city above the first story without having the pots, jars, or boxes protected from falling upon the sidewalks of the streets by strong wire or iron guards, securely fastened to the outer casing of the windows.
(`81 Code, § 95.07) Penalty, see § 10.99