June 21, 2024

The Centennial Light: The Lightbulb Burning for 100 Years

In a firehouse in small town California, is a lightbulb that has burned for 100 years. Known as ‘The Centennial Light’, its inventor was a French electronics genius.

Livermorium on the periodic table
Livermorium on the periodic table

Livermore, population 90 000, is a small town in Alameda County, in central California.

It was founded in 1869 as a railroad town, and early settlers lived a frontier existence. Today it is best known for its science institute, the Lawrence Livermore National Observatory.

In 2000, scientists at the observatory helped fabricate a new element in their particle accelerator. This highly radioactive substance sits at number 116 on the periodic table, and is named after the town: Livermorium.

But Livermore also has another claim to fame: an extraordinary light bulb.

Home of the Centennial Light: Livermore Fire Department, Station 6
Livermore Fire Department, Station 6

In 1972, a marshal at the Livermore Fire Department reported something unusual to the local newspaper, ‘The Tri-Valley Herald’.

A light bulb at Station 6 had been burning, uninterrupted, for as long as anyone could remember. The longest serving member of staff, who had been at the station for decades, advised it had been lit during his entire tenure.

The bulb itself had a distinctive design, and did not look like a modern light. The glass was thicker, and had an uncommon shape, and the filament inside was coiled in an unusual way.

It was in public area, one that needed to be illuminated at all times, and was never turned off. Its striking appearance, and durability, had led to it becoming something of a lucky charm at the station: no one wanted to be on duty when it finally went out.

But the firemen wanted to know more about it: how long had it been burning?

The Centennial Light
The lightbulb burning for 100 years

Mike Dunstan, a reporter at the paper, was intrigued.

He began to investigate, locating and questioning former members of the Fire Brigade, and examining written records. Incredibly, he was able to trace the bulb back a hundred years.

It had originally been purchased by Dennis Bernal, of the Livermore Power and Water Company, in the late 1890s. The bulb had been placed initially in a hose cart, then a garage, before making its way to the fire station, where it had hung ever since.

‘It was left on 24 hours-a-day to break up the darkness so volunteers could find their way.’

– Jack Baird, former Livermore Fire Chief

Aside from a few brief power outages, Dunstan learned that the bulb had been burning continuously since 1901. How to explain its amazing durability?

Humphry Davy, light bulb pioneer
Humphry Davy, light bulb pioneer

The Incandescent Light Blub (ILB) is a 19th century invention.

In 1802, Humphrey Davy, a British scientist, passed an electrical current through two pieces of carbon, which caused an electrical spark between them. A bright light was produced, which Davy demonstrated in public.

Due to passing air currents, the light formed a distinctive, arc like shape. Davy dubbed his invention, the ‘arc lamp’.

An Edison light bulb
An Edison light bulb

Other scientists followed in Davy’s footsteps, as they sought to create a  long lasting, electrically generated source of light.

Most designs featured a ‘filament’, made of material which illuminated when electricity was passed through it. To stabilise the device, the filament was encased in a glass bubble that had the air removed, creating a vacuum.

Different elements and voltages were tried, and the designs steadily improved.

Depending on which version of history you prefer, you could say that either Joseph Swan (1878), or Thomas Edison (1879), produced the first, modern style bulb. But many other scientists and inventors contributed along the way: historians Robert Friedel and Paul Israel studied the history of ILBs, and named 22 inventors whose work was instrumental in their creation.

Once the bulbs were perfected they became commercially available, and a substantial new type of industry was established.

Adolphe Chaillet
Adolphe Chaillet

Adolphe Chaillet was born in Paris, in 1867.

His father was an electrical engineer, who started his own lightbulb business in the 1880s. Many others were doing the same; light bulbs could barely be produced fast enough to keep up with demand, as everyone rushed to replace lanterns and candles with modern lights.

As a child, Chaillet used to accompany his father to work, absorbing the specifics of this new industry. Later, he would study both engineering and physics at university.

Shelby Electric Company factory, Ohio
Shelby Electric Company factory, Ohio

After a stint working for a German light bulb manufacturer, in 1896 Chaillet moved to the United States.

He worked initially for General Electric, and quickly established a reputation: people referred to him as a ‘genius.’ His speciality was improvements to the light bulb’s filament, which was the key to producing better bulbs.

In 1897 he went out on his own, founding the ‘Shelby Electric Company’.

Some of Chaillet's light bulb designs
Some of Chaillet’s light bulb designs

Chaillet now began mass producing bulbs based on his own designs.

To drum up some publicity, he staged a public test, with one of his own bulbs alongside several of his competitors. The bulbs were illuminated, and then subjected to increasing, and variable, voltage:

‘Lamp after lamp of various makes burned out and exploded until the laboratory was lighted alone by the Shelby lamp – not one of the Shelby lamps having been visibly injured by the extreme severity of this conclusive test.’

– Report of the test in ‘The Western Electrician’, 1897

The success of Chaillet’s bulbs was attributed to their filaments, which were an original design he had patented. The wiring was tightly coiled inside the globe, giving them a distinctive look.

A Shelby Electric Co light bulb, and advertising pamphlet
A Shelby Electric Co light bulb, and advertising pamphlet

Chaillet’s reputation, and self-promotion of his product, paid off: business boomed.

Orders came in so quickly they could not be filled. By the end of its first year in operation, the company had doubled in size, and was producing 4 000 light bulbs per day.

Advertising copy of the bulbs claimed they lasted 30% longer, and were 20% brighter, than their competitors.
Among the many buyers: the Livermore Power and Water Co.

Sign for the Edison Electric Light Co
Sign for the Edison Electric Light Co

Despite his initial success, Chaillet faced stiff competition.

General Electric, and the Edison Electric Light Company, were the dominant early manufacturers of light bulbs, and much larger than the Shelby Electric Company. Their resources provided an advantage as the technology continued to advance.

In 1906, tungsten filaments began to be mass produced, and proved brighter and more durable than carbon filaments.

The Shelby Electric Company struggled to manage this transition. Overworked, Chaillet withdrew from his company’s board of directors, and moved to Mexico.

The business was sold to General Electric in 1914, and Chaillet’s innovative designs were mothballed.

A replica of a 1920s lightbulb
A replica of a 1920s lightbulb

The average modern light bulb is designed to last about 1 000 hours. If you plugged one in on January 1 and turned it on, and did not turn it off again, it would likely burn out in mid February.

But in the 1920s, bulbs lasted more than twice as long, averaging about 2 500 hours. This reduction in operational life was deliberate.

A 1920s ad for Phillip's lightbulbs
A 1920s ad for Phillip’s lightbulbs

In 1924, the world’s largest light bulb manufacturers – including General Electric, Osram and Phillips – formed an organisation they called ‘Phoebus’.

Based in Switzerland, Phoebus was nominally in place to allow these corporations to cooperate and share technological innovations, to produce better bulbs. In fact, secretly they agreed to alter their designs to deliberately shorten a light bulb’s life.

A shorter operational life meant more replacement bulbs.

‘It was the explicit aim of Phoebus to reduce the life span of the lamps, in order to increase sales. Economics, not physics.’

– Markus Krajewski, University of Basel, quoted in ‘The New Yorker’

Phoebus was one of the first examples of what came to be known as ‘planned obsolescence’, where manufacturers design their products to fail, so their customers will have to buy replacements.

And it wasn’t just bulbs.

Phoebus would be uncovered and forcibly broken up after World War II, but by this time planned obsolescence had become widespread, and continues to this day in a variety of industries. As the saying goes, ‘It’s bad business to sell someone a product once.’

The Centennial Light in the fire station
The Centennial Light in the fire station

But however you feel about planned obsolescence, there is an enormous difference between bulbs that last for a 1 000 hours, or 2 500, and the Chaillet bulb in Livermore, which has been burning for more than 1 million.

And the extreme durability of the Livermore bulb remains something of a mystery.

While Chaillet’s patent applications are available, these do not provide much detail on the science behind his designs. And direct study of the bulb is impossible while it is still lit.

Other Challiat bulbs are available, and have been examined. These show the trademark coiled filament wire, made of carbon, of a thickness about ten times that of a modern light.

Physics professor Debora M. Katz, who has studied Challiat bulbs, thought the thicker wire may be the explanation for their longevity. Modern bulbs, with thinner wiring, burn hotter and faster, the opposite of a Challiat bulb:

‘Think of it as sort of an animal with a low metabolism. It’s giving us less energy per time, so it can keep on going longer.’

– Debora M. Katz

The bulb, originally designed to give out 60 watts, now produces about 4, the same as a night light.

Katz was also uncertain if this was the explanation. In an interview she quipped that the Livermore bulb might just be a ‘fluke.’

The Centennial Light live via webcam
The Centennial Light live via webcam

Whatever the explanation, the bulb has attained a level of celebrity.

Now referred to as ‘The Centennial Light’, the Livermore bulb is still going strong, and has its own website, and live streamed webcam. There has been an official book, and numerous TV spots. Mythbusters devoted a segment to it.

In 2001, to mark a 100 years of operation, the city threw the bulb a street party. Thousands of people turned out, to celebrate this remarkable light with street dancing, a parade of vintage cars, and live music.


5 thoughts on “The Centennial Light: The Lightbulb Burning for 100 Years

Leave a Reply

Your email address will not be published. Required fields are marked *