Incandescent light bulb granted a Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904. This type is often called Tungsram-bulbs in many European countries. Filling a bulb with an inert gas such as argon or nitrogen slows down the evaporation of the tungsten filament compared to operating it in a vacuum. This allows for greater temperatures and therefore greater efficacy with less reduction in filament life. In 1906, William D. Coolidge developed a method of making "ductile tungsten" from
Longest-lasting light bulbs down in 1937, but the bulb's power was supposedly uninterrupted, according to General Electric, and the bulb continued to burn while a second tower was constructed. However, according to museum curator Jack Stanley, the bulb is fake, consisting of a hollow bulb illuminated by a series of automobile headlights mounted in the display's base. Longest-lasting light bulbs This is a list of the longest-lasting incandescent light bulbs. The world's longest-lasting light bulb is the Centennial Light located at 4550 East Avenue, Livermore, California. It is maintained by the Livermore-Pleasanton Fire Department. The fire department claims that the bulb is at