The forementioned style of arc lights were the first electrically operated street lights in the United States. They provided an intense bright bluish-white light source that was popular for illuminating large areas like this one. These were known as open-style arc lights. They required arc rod trimming and adjusting just about every day. Simply described, two opposing carbon rods mounted close together were employed within a clear glass globe provided a continious electric arc. By the late 1890s "enclosed style" arc lights became on the scene; very similar in basic operation principle. These provided similar bluish-white illumination with less "flicker" and were considerably more energy-efficient with carbon-arc-rod maintenance once every seven to ten days.