LIVERMORE, CALIF. -- Five years after his retirement, ex-firefighter Tom Bramell still likes to visit Station No. 6 for old times' sake, whistling in amazement at all the changes -- the strange faces and slick high-tech engines.

But one thing remains exactly the same, and it's what Bramell misses the most about his firefighting days. The sturdy little object hangs from the ceiling in the firehouse's engine bay, emitting its familiar faint orange glow.

He calls it the long-lived lightbulb of Livermore.

That's actually something of an understatement.

At 107 years and counting, the low-watt wonder with the curlicue carbon filament has been named the planet's longest continuously burning bulb by both Guinness World Records and Ripley's Believe It Or Not.

As objet d'art and enduring symbol of American reliability and ingenuity, it's been lauded by senators and presidents.

It boasts a website -- www.centennialbulb.org, drawing a million hits a year -- a historical society and even a webcam that allows curious fans to check on it 24 hours a day.

The Livermore lightbulb, you see, never gets turned off, which many suspect is the secret to its longevity.

Hanging 18 feet above the floor at the end of a black cloth-covered cord, the little light with the filament the width of a No. 2 pencil lead is unprotected by any lampshade.

Firefighters won't even dust it. Touch it, jokes one captain, and "you get your fingers chopped off."

They guard their light with a surge protector and have a diesel generator and a battery as backups. To them, the bulb is the embodiment of their always-on-duty ethic.

For years, Bramell was known around the Livermore-Pleasanton Fire Department as the keeper of the bulb, the unofficial curator and caretaker who fielded queries from the public and visits from tourists. Over time, he developed a boyish wonder at its craftsmanship and spunk. From a vantage point directly beneath the bulb, Bramell says, its filament even spells the word "on."

Livermore's bulb has burned for nearly a million hours. Even now, in its old age, Bramell will stack it against any New Age fluorescent, halogen or high-pressure sodium bulb out there.

"That bulb predates the atomic bomb and the birth of the automobile," said the onetime deputy chief. "I thought that for sure it was going to go out 35 years ago, but it fooled me. It fooled everyone."

Bramell said there are numerous theories on the bulb's longevity. "Most people just consider it a freak of engineering," he said. "But I believe the bulb has stayed alive so many years because the makers gave it a perfect seal, so no air gets inside the bulb to help disintegrate the carbon filament. This bulb operates in a vacuum and it doesn't burn hot. That's the secret."

In 1901, when the tiny bulb was first screwed into place inside a so-called hose cart house, it cast its light on a simpler era.

Back then, horse-pulled carts carried water to fires. The bulb burned day and night, hanging at eye level from a 20-foot cord. Its job: to break the darkness so firefighters responding to calls wouldn't have to fumble to light the wicks of their kerosene lanterns. Manufactured by the Shelby Electric Co. of Shelby, Ohio, the bulb soon outlived its maker, which closed in 1914.

Later, in the main firehouse, it illuminated more modern rigs as horses were replaced by gas-fed engines.

It didn't always receive kid-glove treatment.

Climbing atop their engines, firefighters returning from World War II and Korea often would give the bulb a playful swat for good luck. The next generation -- the Vietnam veterans and the younger kids -- used it as a target for Nerf basketball practice.