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Several inventors hit upon the idea of creating light with glowing wires, relatively early. Experiments with platinum wires and charcoal strips, which were made to glow with the aid of electricity, were already being carried out in the 1830s and 40s.
In part, evacuated glass bulbs were already being used here in order to avoid oxidation. However, the platinum burnt out quickly and the vacuum pumps were unable to create a sufficient vacuum. Electricity supply was also a problem as only batteries were available at that time. It was not until 1866 that Werner von Siemens discovered the principle of the dynamo and constructed machines which provided a constant flow of electricity.
In 1854, the German precision mechanic, Heinrich Goebel, constructed the first light bulb to burn for a sustained period of time. He used charred bamboo threads as a filament and evacuated the glass bulb by filling it with quicksilver, allowing the quicksilver to flow out and then fusing the bulb shut.
The American Thomas Alva Edison developed the first commercially successful incandescent light bulb in 1879 – a carbon bulb which went into mass production. He also provided the necessary fittings such as a switches, lamp holders, distributors and suitable dynamos. As advertising was already important for success in those days, Edison showed a much admired installation of thousands of his bulbs at the Paris Electrical Exhibition in 1881.
In 1900, the first filament was developed from the metal osmium. This kind of osmium lamp consumed only half the energy of a carbon thread lamp whilst producing the same amount of light.
In 1903, the first electric light bulb with a tantalum filament was developed in Berlin and shortly afterwards, filaments made of tungsten, the metal with the highest melting point, were tested. The tungsten lamp consumed only a third of the power required by a carbon thread lamp to achieve the same brightness – the material had been found which is still used in light bulbs today.
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