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There is no need to dwell on the blessings of artificial light; they are obvious. Nevertheless, half the work the world does today could not be if we had to depend entirely on the light of the sun.
The earliest artificial light was the fire, lit for warmth cooking purposes. The torch must have been originally simply a burning stick taken out of the fire; it was perfected when it was discovered it would burr longer and more brightly when dipped in oil or fat.
The use of fat on the torch may have the rush-light, which consisted simply of a rush-stem or some tow floating in a vessel of oil or liquid fat. The Indian chiragh is on just the same . Unfortunately, both the torch and the rush-light were very imperfect, the one giving off thick clouds of smoke and the other producing a very dim light.
The candle was a great improvement over the rush-light, as it was a wick of cotton enclosed in a pillar hard and solidified fat. Still, the final development of the rush-light was the lamp, burning a mineral oil (such as kerosene) and often giving hundred-candle power light.
So far, the principle of all artificial light was the same: they were all oil lights. But the discovery of the quality of coal gas at the beginning of the 19th century led to a new form of artificial light, namely, gas. And for the part of the 19th century, gas was the chief kind of artificial light used in towns. It gave better light than or candles, and was much more convenient, but it had its dangers, and was liable to foul the air of the rooms in which it was burning.
The light, which came into common use in the last century, is the queen of artificial lights. It has great advantages over every other . It gives a much more brilliant illumination, is clean and gives off no smell, does not consume the oxygen in the air, is cool produces little heat, and is very convenient. No one who has had electric light in his house ever to go back to gas, lamps, or candles.