This was the first type of street lighting fixture in the United States that operated by electricity and were introduced about 1880. These operated via two carbon rods vertically/physically opposing each other providing a brilliant electric arc in the air gap between the ends of the rods. The latter had to be replaced and adjusted every day or two. By 1900 similar, improved and more energy-efficient arc lighting fixtures were becoming commonplace; these were somewhat smaller in fixture size and the arc was contained within a glass globe. Their arc rods required replacement and adjustment once every ten days or so. Most electric arc lights used for street lighting operated on 6.6 ampere series circuits (the same that ran incandescent street lamp bulbs).