35 Business operation of port facilities for others; customs clearance services; business operation of sea walls, jetties, piers, wharves, docks, boat landings, warehouses, storehouses, elevators, grain- bins, cold storage plants, terminal icing plants, bunkers, oil tanks, ferries, canals, locks, tidal basins, bridges, subways, tramways, cableways, conveyors, administration buildings, fishing terminals and modern appliances pertaining to all of the above