At 107, still a real live wire

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.

Then, in 1972, a local reporter checked records and interviewed old-timers to trace its history. Firefighters suddenly realized they had a treasure.

"The good-luck slaps and target practice stopped," Bramell recalls. "We figured, 'Wow, maybe we should take care of this bulb.' "

The bulb was soon featured in the book "On the Road with Charles Kuralt." "In a time when gadgets are forever falling apart or burning out or breaking up, it was kind of nice spending a day watching a dusty, 71-year-old lightbulb just go on and on," the newsman wrote. "If you're ever in Livermore and need reassurance, we recommend it."

Thousands took his advice, traveling to the East Bay community of 80,000 to see the bulb and sign its guest book. "Beats Vegas!" wrote one. And another: "How many firemen does it take to change a lightbulb in Livermore? None, it never needs changing."

Bramell has heard from ministers who sermonized about the bulb's enduring reliability and residents who say they use it as a litmus test for new friends: Those who "get" the light's significance show the wisdom and good judgment for lasting ties.