Livermore's mysterious lightbulb burns 110 years LIVERMORE

Declared the oldest known working light bulb by Guinness Book of World Records and Ripley's Believe-It-or-Not in 1972, the centennial bulb hangs from the ceiling of Livermore Fire Station #6 on Thursday Feb. 3, 2011, in Livermore, Ca. The light bulb was first switched on at fire department hose cart house on L Street in Livermore in 1901. less Declared the oldest known working light bulb by Guinness Book of World Records and Ripley's Believe-It-or-Not in 1972, the centennial bulb hangs from the ceiling of Livermore Fire Station #6 on Thursday Feb. 3, ... more Photo: Michael Macor, The Chronicle Photo: Michael Macor, The Chronicle Image 1 of / 5 Caption Close Livermore's mysterious lightbulb burns 110 years 1 / 5 Back to Gallery

Some mysteries never dim with time. One of them is hanging from an electrical wire in Livermore.

At Livermore Fire Station No. 6 is a lightbulb that has not burned out in 110 years. Nobody, even in this golden age of technology, knows why. And no one wants to unscrew the bulb to find out.

"It still gives that warm, comfy glow," said retired Livermore fire Division Chief Lynn Owens. "In this transient modern world, this lightbulb is really something you can trust. And nobody knows the mystery of it."

The lightbulb is about 3 inches long and slightly rounder than a modern lightbulb. Inside the hand-blown glass is a jumble of carbon filament that radiates about 4 watts of soft orange light - about the strength of a nightlight.

Its 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 cub reporter 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 electrician), calm as can be, lightly tapped the switch and it came on again."

The bulb has been the subject of dozens of news stories, magazines, books and television shows. It's featured in the Guinness Book of World Records and Ripley's Believe It or Not.

Dubbed the Centennial Bulb, it is a wonder among engineers and advocates of energy-efficient lightbulbs.

It's featured in a soon-to-be-released documentary, "The Lightbulb Conspiracy," about the planned obsolescence of lightbulbs.

Double-decked tour buses often stop by the fire station for viewing. The guest book shows visitors from China, Germany, Fresno and beyond.

Despite its worldwide fame, the bulb has humble beginnings. It was created in the late 1800s by the Shelby Electric Co. in Shelby, Ohio, according to retired Sandia technician Steve Bunn, who's devoted his retirement to studying the bulb.

A French inventor named Adolphe Chaillet held the patent, and the bulb's secret probably died when he did.

Others have tried to decipher the mystery, however. Scientists - of which there are thousands around Livermore and its labs - have studied it for decades. Some, like David Tse, an electrical engineering professor at UC Berkeley, are skeptical.

"It's not possible. It's a prank," he said curtly, slamming down the phone.

Henry Slonsky, an electrical engineering student at San Francisco State, was more open-minded.

"It's highly unlikely, but it's possible if the bulb has a really strong vacuum," he said. "And back then they did make everything way over the top."

The bulb made its way from Shelby to Livermore via Dennis Bernal, owner of the local power company. After he sold the company, he donated surplus bulbs to the Fire Department.

Generations of firefighters have relied on the bulb's soft glow to guide them, from the days of horse-drawn carts to today's giant engines.

"We used to touch the bulb for good luck on our way to fires," said Owens, who worked alongside the bulb for 30 years. "But all that came to a screeching halt when we realized the bulb's significance."

Current firefighters swear they don't sneak into the firehouse at night to change the bulb.

"We're the Fire Department. We're very trustworthy," said firefighter Roy Andora. "You trust us with your lives. You can trust us with a bulb."

Fans of the bulb have no doubt of the bulb's power. They watch it on a 24-hour webcam at www.centennialbulb.org. They know it's real.

"I equate it with a pet rock or a hula hoop," said Dick Jones, a retired Sandia engineer who specializes in photographing the bulb. "It's just one of those things that people seem to like."

Livermore is planning a party June 18 for the bulb, assuming no one accidentally smashes it before then.