No ordinance granting a franchise or any valuable privilege in the city shall be passed on the day of its introduction, nor for thirty days thereafter, nor until such ordinance shall have been published in at least one issue of the official newspaper of the city and after such publication such proposed ordinance shall not thereafter and before its passage be amended in any particular where the amendment shall impose terms, conditions or privileges less favorable to the city than the proposed ordinance as published, but amendments favorable to the city may be made at any time and after publication. Such publication shall be at the expense of the applicant: Provided, that an ordinance granting a franchise to lay a spur, railroad track or tracks, connecting manufacturing plants, warehouses or other private property with the main line of railroad, need not be published before the same be passed by the Council. No franchise or valuable privilege shall be created or granted by the City Council otherwise than by ordinance, and the passage of any such ordinance shall require the affirmative vote of two-thirds of the Councilmen elected. All publications of ordinances granting a franchise, both before and after passage, shall be made at the expense of the applicant or grantee. Where an ordinance granting a franchise or valuable privilege is sought to be amended after the same shall have been in force, the provisions of this section as to publication before final action upon such amendment shall apply as in cases of proposed ordinances granting original franchises.