Incandescent Lamp

   The Incandescent Lamp is an electric lamp consisting of a glass bulb in which the current is made to pass through a wire, filament, or strip of some substance which, because of its high resistance, becomes greatly heated, and hence brilliantly incandescent. In the early days of incandescent electric light, the only suitable substance known was carbon. This was carefully prepared in the form of a thin strip or wire, from bamboo or some similar material, bent in a loop and enclosed in a bulb from which the air had been exhausted, so as to create a vacuum.