Immediately upon the adoption of such resolution the city manager or his duly authorized representative shall cause written notice thereof to be given to the owner, person in possession thereof, or having an interest of record in, every piece of land sought to be appropriated, or to his authorized agent; and such notice shall be served by a person designated for the purpose, and return made in the manner provided by law for the service and return of summons in civil actions. If such owner, person, or agent, cannot be found notice shall be given by publication once a week for three consecutive weeks in a newspaper of general circulation in the city, and the commission may thereafter pass an ordinance directing such appropriation to proceed.