N.C. Gen. Stat. § 104-2: Unused lands to revert to State.

The consent given in G.S. 104-1 is upon consideration of the United States building lighthouses, lighthouse keepers' dwellings, lifesaving stations, buoys, coal depots, fish stations, post offices, customhouses, and other buildings connected therewith, on the tracts or parcels of land so purchased, or that may be purchased; and that the title to land so conveyed to the United States shall revert to the State unless the construction of the aforementioned buildings be completed thereon within 10 years from the date of the conveyance from the grantor. (1870-1, c. 44, s. 5; Code, ss. 3080, 3083; 1887, c. 136; 1899, c. 10; Rev., s. 5426; C.S., s. 8054.)