Electric light by the first practical electric arc light in 1806. By the 1870s, Davy's arc lamp had been successfully commercialized, and was used to light many public spaces. The development of a steadily glowing filament suitable for interior lighting took longer, but by the early twentieth century inventors had successfully developed options, replacing the arc light with incandescents. The energy efficiency of electric lighting has increased radically since the first demonstration of arc lamps and the incandescent light bulb of the 19th century. Modern electric light sources come in a profusion of types and sizes adapted to many applications. Most modern
Tapis crude allows for greater production of higher-value products, such as petrol, than from Brent or WTI. Its high price is also due to the purity of the blend. Because it contains less sulfur it requires less refinery processing than sourer crude oils such as Brent Oil and WTI. Malaysia is the only country which has significant amounts of oil produced as Tapis, from fields located in the South China Sea. Tapis crude Tapis crude is a Malaysian crude oil used as a pricing benchmark in Singapore. Tapis is very light, with an API gravity of 43°-45°, and very sweet, with only