Some are very plain and functional, while some are pieces of art in themselves. The most important functions are as a holder for the light source, to provide directed light and to avoid visual glare. Lighting fixtures come in a wide variety of styles for various functions. The final death knell for whale oil was in 1859, when crude oil was discovered and the petroleum industry arose. By 1860, there were 33 kerosene plants in the United States, and Americans spent more on gas and kerosene than on whale oil. In the 1850s, the price of whale oil dramatically increased (more than doubling from 1848 to 1856) due to shortages of available whales, hastening whale oil's decline. The use of whale oil declined after Abraham Gesner, a Canadian geologist, first refined kerosene in the 1840s, allowing brighter light to be produced at substantially lower cost. Chandeliers were an early form of " light fixture".Ī major reduction in the cost of lighting occurred with the discovery of whale oil.
Candles and glass and pottery lamps were also invented. Fireflies have been used as lighting sources. Oily animals (birds and fish) were also used as lamps after being threaded with a wick. Hundreds of these lamps (hollow worked stones) have been found in the Lascaux caves in modern-day France, dating to about 15,000 years ago. Lamps typically used animal or vegetable fats as fuel. These lamps were made from naturally occurring materials such as rocks, shells, horns and stones, were filled with grease, and had a fiber wick. Prehistoric people used primitive oil lamps to illuminate surroundings. As early as 400,000 years ago, fire was kindled in the caves of Peking Man. With the discovery of fire, the earliest form of artificial lighting used to illuminate an area were campfires or torches.
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