File:Welsbach System of Incandescent Gas Lighting Catalog - DPLA - d7ef3100fd8fd342dd292779dc0a7adf (page 59).jpg

The Welsbach company produced this pamphlet around 1889 to promote its system of gas lighting. The brochure includes a depiction of the factory in Gloucester, New Jersey, and several illustrations of lighting system components including mantels, burners, and air shutters. The brochure emphasizes the ways that incandescent mantels are superior to previous gas light technologies. Welsbach claimed its system was cleaner-burning, produced a more pleasant quality of light, and minimized the "vitiation of the air" or, it did not consume too much of the room's oxygen as it burned. In the 1880s, Austrian chemist Carl Auer von Welsbach (1858-1929) created fabric impregnated with thorium and cerium, which glowed incandescently when heated by burning gas. Mantels for gas lamps were the first industrial product to use rare earth elements and led to international trade in rare earth ores, especially monazite. Welsbach managed firms around the world that sold gas lamps for lighting streets, homes, and businesses, which shaped the visual landscapes that millions of people inhabited from the 1890s into the 1930s. In the United States, the Welsbach Incandescent Gas Lighting Company had offices on Walnut Street in Philadelphia, and a factory on the Delaware River at Gloucester, New Jersey. Many of the factory workers were women, who sewed the fabric mantels and packed the mantels into packages for sale across the country.