 He created a new lighting system based on Argand lamps; in 1812 the United States Congress purchased his patent rights for the system.In so doing, it awarded him a contract to equip all American lighthouses with the lamps; the fitting took four years.In 1815 Lewis won another contract with Samuel H. Smith, Commissioner of Revenue, which gave him a monopoly over the provision of winter pressed Spermaceti oil for lighthouses throughout the eastern seaboard.