workings may be a mystery, but it's probably the most well-documented lightbulb in history. It was first installed in a Livermore firehouse on L Street in 1901, replacing the kerosene lanterns that helped firefighters load hoses and shovels for night calls.

At the time, lightbulbs - at least practical ones that lasted more than 12 hours - had been around for only about 20 years.

Between 1901 and 1903, the then-60-watt bulb was moved to a firehouse on Second Street, and then to a new station on First and McLeod streets.

For the next 71 years, the bulb languished in anonymity. No one seemed to notice that the bulb never made that telltale pop and fade to black. It was just always on.

But that changed in 1972, when an intrepid cubreporter named Mike Dunstan at the Livermore Herald News cracked the story with a lengthy investigative piece suggesting Livermore's glowing orb was possibly the oldest functional lightbulb on Earth.

The bulb became world-famous overnight. So when the old firehouse closed four years later, panic set in when it came time to unscrew the bulb and move it a mile away to the new firehouse on East Avenue.

The city's chief electrician was called in to turn it off, gently unscrew it and place it in a special foam box. It was moved with full police and fire escort, and 2 1/2 minutes later, the electrician screwed it in at the new firehouse.

"At first it didn't go on. There was a gasp from the crowd," Owens said. "But then Frank (the