To produce a mantle, cotton is woven or knit into a net bag, impregnated with soluble nitrates of the chosen metals and then heated the cotton burns away, and the nitrates are converted to nitrites, which fuse together to form a solid mesh. The gas mantle remained an important part of street lighting until the widespread introduction of electric lighting in the early 1900s. After introducing this new mantle commercially in 1892, it quickly spread throughout Europe. In 1891 he perfected a new mixture of 99% thorium dioxide and 1% cerium dioxide that gave off a much whiter light and produced a stronger mantle. In 1889, Welsbach received his first patent mentioning thorium, March 5, 1889, US patent #399,174. Carl Auer von Welsbach's first company established a factory in Atzgersdorf in 1887, but it failed in 1889. These original mantles gave off a green-tinted light and were not very successful. His first process used a mixture of 60% magnesium oxide, 20% lanthanum oxide and 20% yttrium oxide, which he called 'Actinophor' and patented in 1887, US patent issued on March 15, 1887, # 359,524. Ignaz Kreidl worked with him on his early experiments to create the Welsbach mantle. The modern gas mantle was one of the many inventions of Carl Auer von Welsbach, a chemist who studied rare-earth elements in the 1880s and who had been Robert Bunsen's student. This device was made from a cleverly produced matrix of magnesium oxide, which did not need to be supported by a platinum wire cage, and was exhibited in the Crystal Palace exhibition of 1883. The first effective mantle was the Clamond basket in 1881, named after its inventor. Many early attempts used platinum- iridium gauze soaked in metal nitrates, but these were not successful because of the high cost of these materials and their poor reliability. In the late 19th century several inventors tried to develop an effective alternative based on heating a material to a lower temperature but using the emission of discrete spectral lines to simulate white light.

Limelight was invented in the 1820s, but the temperature required to produce visible light through black-body radiation alone was too high to be practical for small lights. The mantle shrinks after all the fabric material has burned away and becomes very fragile after its first use.įor centuries, artificial light has been generated using open flames. This concentration of combustion inside the mantle improves the transfer of heat from the flame to the mantle.

The mantle aids the combustion process by keeping the flame small and contained within at higher fuel flow rates than in a simple lamp. The combination of these properties yields a mantle that, when heated by a kerosene or liquified petroleum gas flame, emits intense radiation that is mostly visible light, with relatively little energy in the unwanted infrared, increasing the luminous efficiency. There is also some evidence that the emission is enhanced by candoluminescence, the emission of light from the combustion products before they reach thermal equilibrium. The rare-earth oxides ( cerium) and actinide ( thorium) in the mantle have a low emissivity in the infrared (in comparison with an ideal black body) but have high emissivity in the visible spectrum. A mantle glows brightly in the visible spectrum while emitting little infrared radiation. The fibers are impregnated with metallic salts when the mantle is first heated in a flame, the fibers burn away in seconds and the metallic salts convert to solid oxides, forming a brittle ceramic shell in the shape of the original fabric. The mantle is a roughly pear-shaped fabric bag, made from silk, ramie-based artificial silk, or rayon. An 85 mm Chance Brothers Incandescent Petroleum Vapour Installation

Luminous silk foundation