Nonconformities are declared by this Zoning Ordinance to be incompatible with permitted uses in the districts in which such uses are located. A nonconforming use of a structure, a nonconforming use of land, or a nonconforming use of a structure and land in combination shall not be extended, nor shall the same be extended or enlarged in ground covering, floor area, or volume after passage of this Zoning Ordinance by attachment on a building or premises of additional signs intended to be seen from off the premises announcing such non-conforming use(s), nor by the addition of other uses of a nature which would be generally prohibited in the district in which such use is located.