Any company operating a railroad in whole or in part within this state which has posted proper notice to that effect in a conspicuous place in each waiting room and on the front of its depot building may collect ten cents in addition to the fare allowed by law when such fare is paid on the train, if an office at the point at which the passenger boarded the train was open for the sale of tickets at least thirty minutes next prior to the departure of such train.
R.C. § 4965.51