All additions, lots, lands, subdivisions, and parcels of ground included within the official municipal map and plat on file at the office of the County Register of Deeds, having been by act or ordinance of the governing body or by law duly annexed to or made a part of this municipal or having been by the act, authority, acquiescence, consent, platting, and dedication of their respective owners, created either as the original townsite or as additions to the municipality are hereby declared to be within the corporate limits of the municipality. Lawfully constituted additions or changes in the municipal limits shall be indicated upon the maps and plat by the Municipal Engineer after the addition or change has been completed in accordance with the ordinances of this municipality and the laws of the state.
(`75 Code, § 11-101)