No ordinance or ordinances authorizing any such improvement, where the whole or any part of the cost of the improvement is to be assessed against abutting property, shall be finally adopted until the expiration of thirty days from the date of its introduction, and, in the meantime, copies thereof shall be published, once a week for two weeks, in one newspaper circulating in such city, borough and township immediately following the introduction thereof, and at least five copies thereof shall be posted along the line of the proposed improvement.
53 P.S. § 1863