The first successful use of a filament in for an electric lamp or light bulb was made of carbonized cotton thread and looped in a hair-pin fashion. It was charcoal black in color and threadlike in appearance and mounted in a hairpin configuration. This was the design that Thomas Edison used in his first successful electric lamp experiment in October of 1879.  Edison’s thread was said to have been supplied by his wife from her sewing kit.  It supposedly burned for some 40 hours, though some reliable sources state that it burned for 13 ½ or 14 ½ hours.  In any case, this successful filament practically “electrified” the world” and paved the way for the wide spread use of incandescent lighting.

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