Any port or harbour authority or dock company which shall have reason to believe that any railway company is by its rates or otherwise placing their port, harbour, or dock, at an undue disadvantage as compared with any other port, harbour, or dock to or from which traffic is or may be carried by means of the lines of the said railway company, either alone or in conjunction with those of other railway companies, may make complaint thereof to the Commissioners, who shall have the like jurisdiction to hear and determine the subject-matter of such complaint as they have to hear and determine a complaint of a contravention of section two of the Railway and Canal Traffic Act, 1854, as amended by subsequent Acts.