If, after hearing and investigation as provided by Chapters 4901., 4903., 4905., 4907., 4909., 4921., 4923., and 4925. of the Revised Code, the public utilities commission finds any charge, regulation, or practice affecting the transportation of passengers or property, or any service in connection therewith, not specifically designated, unreasonable or unjustly discriminatory, it may regulate it as provided by such chapters in such cases.
R.C. § 4907.09