(a)fix the maximum or minimum rate [per kilometer] [Substituted by Act 13 of 1930, Section 25, for "per mile" (w.e.f. 1.5.1978).] which may be charged for passenger fares for passengers of any class travelling on inland [Mechanically Propelled Vessels] [Substituted by Act 35 of 1977, Section 5, for "steam-veseel" (w.e.f. 1.5.1978).]