Where uncertainty exists with respect to the boundaries of the various districts as shown on the map accompanying and made a part of this Zoning Ordinance, the following rules apply:

   1.   The district boundaries are either street lines or alley lines otherwise shown; and where the districts, designated on the map accompanying and made a part of this Zoning Ordinance, are bounded approximately by street lines or alley lines, the street lines or alley lines shall be construed to be the boundary of the district.

   2.   In unsubdivided property, the district boundary lines on the map accompanying and made a part of this Zoning Ordinance shall be determined by the use of the scale appearing on the map.