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Plants Art From Old Light Bulbs
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In 1901, American businessman Frank A. Poor purchased the Merritt Manufacturing Company, the predecessor to North American light bulb makers Hygrade and Osram Sylvania. Poor's firm in Middleton, Massachusetts, specialized in refilling burned-out light bulbs.
In 1903, Willis Whitnew invented a metal-coated carbon filament that would not blacken the inside of a light bulb.
On December 13, 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted a Hungarian patent (No. 34541) for a tungsten filament lamp, that lasted longer and gave a brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904, so this type is often called Tungsram-bulbs in many European countries. Their experiments have also shown that the luminosity of bulbs that were filled up with an inert gas was higher. The tungsten filament outlasted all other types.
In 1906, the General Electric Company patented a method of making filaments from sintered tungsten and in 1911, used ductile tungsten wire for incandescent light bulbs.
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