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Cavemen always used fat to make the oil lamps. For thousands of years people obtained light from animal fats and olive oil. Later, a new improved kind of oil lamp was invented.
The Stone Age people were comforted at night only by oil lamps. Eskimos, living in the Arctic, until quite lately have used the oil lamps in the shape of a saucer. The oil (a kind of seal fat) was sunk into the wick made of moss, which burnt until there was no oil left.
The Romans used rock oil for their lamps. In 1680, the streets of London were lit by oil lamps.
In 1784, the Swiss scientist Aime Argand constructed an improved kind of oil lamp. It was equipped with glass protecting the wick and delivered much stronger light. In the nineteenth century many houses were lit only by lamps using paraffin oil.
Gaslight and electric light were introduced a little later.
The first well-known source of electric light was an electric arc working by means of a constant electric flash-over. The flash-over was evoked by Humpry Davy in 1802 in England. Unfortunately, the arc was too bright to be used at home.
At the end of the second half of the nineteenth century, in many Countries there were a lot of undertakings to invent an electric bulb, that is the mechanism, whose lighting fibre (the so called filament) lighted under the influence of the electric current that ran through it. The bulb pioneers had to overcome a great deal of difficulties. They had to choose the proper material for the lighting fibre to deliver electric current, without melting because of the heat. They had to obtain quite a big vacuum so that the included wick would not oxidise. Because of the limited range of materials that fulfilled the required conditions and lack of sufficient mechanisms allowing to obtain high vacuum, their achievements were insignificant.
R. W. Grove’s undertakings and experiments with platinum (1840), F. De Moleyns’ with charcoal and platinum (1841), E. W. Staite’s with the mixture of platinum and iridium, H. Goebl’s with burnt bamboo fibre (1854) and A. Lodygin’s with retort coal and many other – all of them resulted in primitive bulbs lighting only for several minutes.
Among the early bulb pioneers, the most important advocate was J. W. Swan, the British scientist, who used the coal fibre in 1848, but obtained positive results only in 1878.
The entirely practical, fully useful bulb was invented by the scientific team in the laboratory in Menlo Park (USA) under the leadership of Thomas Edison. After long hard work they succeeded in constructing (21st Oct 1879) the bulb with coal fibre (graphite fibre obtained from wool thread) lighting for several hours. Then, they prolonged the time of lightning to over a hundred hours.
On New Year’s Eve in 1879 Edison was able to illuminate Menlo Park, using 800 of his bulbs.
In 1880, the ship Columbia was equipped with electric lighting and in 1882 the first power station in New York supplied the current to 7200 bulbs under the voltage of 110 V. At the end of the Nineteenth century, the superiority of bulbs over other sources of lights was clearly visible and since the beginning of the Twentieth century the bulb has had the priority over other kinds of artificial lighting.
In the Twentieth century, the osm wires were used in bulbs (1905) and the wolfram wires were introduced (1907); the bulbs were filled with weakened neutral gas – first with argon then with krypton. The modern bulb filled with argon and with wolfram wire curled in a spiral was constructed in 1913 by I. Langmuir. About 1930 the two-curled wolfram filament was introduced and it is used until present times.
The present bulbs are made in numerous shapes, which can be connected with frosted glass – then they can be used with no lamp-shade.
Further works on the improvement of bulbs led to the construction in 1959 of the bulb with regenerative iodic cycle by Zubler and Mosby. Those iodic bulbs work by means of introduction into their interior – apart from the neutral gas, for example argon, krypton or xenon – of small amounts of clear iodine (halogen), which changes into steam during the time of lighting. Iodic bulbs differ in shape from the conventional ones because of some constructional aspects. They are most often pipes. They are much more resistant to heat and mechanical damages. They are 60 % better and have got a perfect colour of light. They are used to light airports, stadiums, yards and cars. Lately, there have been undertakings to replace the iodine with fluorine.
Searching for more perfect sources of light than the bulb, led in XX century to the construction of the flash-lamp in many varieties. The activity of such lamp consists in emission of light (that is visible radiation) by the induced atoms of gas that fill up the lamp. The induction of gas atoms causes a flash-over inside the gas. The colour of light depends on the kind of gas induced (neon, sodium or mercury vapour).
The first flash-lamp was constructed in 1910 by G. Claude who used neon. The flash-lamps filled with rarefied neon or other gas, or with the metal vapour, which are widely known today as neons, fluorescent tubes or fluorescent lamps give off coloured light and are used mainly for advertisement. The luminous efficiency of a flash–lamp is a couple of times greater than that of the electric bulb. The drawback of the flash-lamp, especially of the sodium or mercury lamps, is the annoying light colour that distorts the real tinges of the lighted objects. In spite of this fact, sodium lamps - giving off yellow and orange light that easily pierces through the fog - are used for the illumination of the bridges. Mercury lamps, however, which give off blue and green light are used in physiotherapy for medical irradiation, because they include a lot of ultraviolet rays.
Working over the improvement of the flash–lamp led to the creation of another variation, widely known as the fluorescent lamp as well as the high–pressure flash-lamp which are both used to illuminate huge areas such as squares and streets, and also for scientific purposes.
In 1965 another kind of illumination occurred, the so called lighting bands. They can be installed inside the buildings or outside to light roads and squares. They can be battery or electric-network operated. The lighting bands are thin (about 8 mm) and flexible; they can be produced in different colours and tinges, and they can be optionally shaped. Such a kind of illumination is based on the usage of the phenomenon of electro luminescence.
In spite of the searching of a more perfect source of artificial light than the electric bulb, the hegemony of the bulb has not been suppressed yet. The electric bulb is widely present in our everyday life. The developing civilisation put the man away from the natural rhythms of living. We live more intensely so our activity does not end when the evening comes. We work, read, learn and rest also when we are surrounded by darkness. Artificial illumination is not only a pleasant feeling of safety but it is a necessity which enables our normal functioning. The bulb is the basis for our artificial illumination. We can realise the importance of electric energy and the bulb during temporary blackouts. Candles and flash–lights help us in those uncomfortable situations but normal functioning is entirely disorganised. So I dare say that civilised living cannot exist without electric energy and the bulb; at least until that moment when there will be another widely used source of light and successor of the bulb.