How many times did Edison fail in attempting to invent the lightbulb?

The answer is not around number like 1,000 or 10,000 times that some people like to claim. It took 2,774 attempts to arrive at the bamboo filament that made Edison's lightbulb a commercial success, though he was not the one who invented the electric light.

Electric lights  in England

Various inventors dabbled in channeling electricity for light many decades before Edison did. Credit for the first electric light goes to the British chemist Humphry Davy who invented the Electric Arc lamp in the first decade of the 19th century,  though is more famous for the lamp that bears his name invented in 1815.

Another English chemist, Warren de la Rue offered a design in 1840 that relied on a coiled platinum filament in a vacuum tube. Thought it worked quite well, the high cost of platinum rendered the bulb too expensive for mass production.

In 1850 an English physicist named Joseph Wilson Swan used carbonized paper filaments for his bulb design.  It took yet another decade to make a working prototype, though it was still  not viable as a commercial product. It took him until 1878 to developed a bulb  that relied on treated cotton thread, which both increased longevity and removed the problem of early bulb blackening.

A light across the Atlantic 

In the interim, on the other side of the Atlantic, a patent for the Woodward and Evan’s Light was filed in Canada on July 28, 1874.They used carbon rods held between electrodes in glass cylinders filled with nitrogen. While the product worked, Canada is not really recognized as the cradle of electric bulbs. 

That's because even though Woodward obtained an American patent in 1876, he wasn't able to launch his bulbs in the U.S.  In 1879 Thomas Edison bought out the patents from Woodward and his Canadian partners. Then in 1885 Woodward sold a share of his Canadian patent to Edison, as well. But that doesn't mean that Edison merely capitalized on the work of others. 

Edison's own advancement

Edison did make a significant advance in lightbulb design in developing a filament was made from carbonized bamboo, which allowed it to burn for over 1200 hours. It was that design that was put into mass production.

Remember Swan over in England? According to "Who Invented the Light Bulb?"  Edison's own lightbulb design was to close too that of Joseph Swan's to be  awarded its own patent. But in the spirit of "if you can't lick 'em join 'em," Swan and Edison partnered up in 1880 to develop a viable lightbulb. Edison's patent was awarded on January 27, 1880.

 Exactly how many attempts did it take to get the right filament for  Edison lightbulb?

While we there was no actual tabulation of all the steps along the way, there is a very precise number connected to the experiments surrounding the bamboo filament -- 2,774. 

It's cited in a Rutgers newsletter on the Thomas Edison papers here:

No one, including Edison, ever counted the number of experimental lamps that they made. There were hundreds of experiments before he developed the bamboo lamp. And many additional experiments before the lamps were adequate for commercial production. In a letter to Edison in spring 1884, Francis Upton noted that the lamp factory had conducted 2,774 experiments (presumably since it had started operations in October 1881).

The link in the paragraph above take you to a digital image of a handwritten note on the bamboo lamp. 

What about the inspiration of not giving through thousands of failures? 

What to make of the famous quote about Edison claiming not to have failed 10,000 times but to have

Inside Edison's lab. Photo by Ariella Brown

 found 10,000 ways that did not work?

There's no record of that quote with respect to the electric bulb, though he did say something like that about  his experience with the battery. The Rutgers newsletter dug up a quote that comes pretty closed in Edison: His Life and Inventions. an authorized biography by Frank Dyer and T. C. Martin, first published in 1910. Edison's friend and associate, Walter S. Mallory, offers this account:

This [the research] had been going on more than five months, seven days a week, when I was called down to the laboratory to see him [Edison]. I found him at a bench about three feet wide and twelve feet long, on which there were hundreds of little test cells that had been made up by his corps of chemists and experimenters. I then learned that he had thus made over nine thousand experiments in trying to devise this new type of storage battery, but had not produced a single thing that promised to solve the question. In view of this immense amount of thought and labor, my sympathy got the better of my judgment, and I said: 'Isn't it a shame that with the tremendous amount of work you have done you haven't been able to get any results?' Edison turned on me like a flash, and with a smile replied: 'Results! Why, man, I have gotten lots of results! I know several thousand things that won't work!'

There you have it, not exactly in the words you find on quotes sites, but the same idea. The point is that Edison had to go through a great deal of trial-and-error to discover what would make the bulb work well. That required more persistence than flashes of insight, which is why Edison is associated with another quote: "Genius is one percent inspiration, ninety-nine percent perspiration" Spoken statement c. 1903 that was published in Harper's Monthly in September 1932.

[Note: this blog has been updated multiple times since it was first published with references to events that occurred after 2015. I talk about that in this What Edison Can Teach Us About SEO.]

Shedding some light on Latimer

I'm adding in another note on the development of the lightbulb to clarify some confusion stirred up by Joe Biden's declaration in Kenosha on September 3, 2020, "A black man invented the light bulb. not a white guy named Edison. Okay?"

One thing Biden got right is that a black man named Lewis Howard Latimer did advance light bulb

designs. Latimer was a remarkable inventor, electrical engineer, and patent expert who advanced light bulb design. He did work for Hiram Maxim, as well as Edison.

Lewis Howard Latimer

While  working as a draftsman for Hiram Maxim, founder of the U.S. Electric Lighting Company, he along with Joseph Nichols, registered a patent for a light bulb with a carbon filament that burned better than than the bamboo one in 1881. He also got the patent on or ‘the process of manufacturing carbons’ which was an improvement on the method for the production of the carbon filaments in light bulbs.

Latimer only started working for the Edison Electric Light Company in 1884 and remained at that New York City location until 1896; he never worked alongside Edison as a "mucker" in the Menlo Park Lab.  As chief draftsman and patent expert in the legal department of Edison Electric Light Company. Among his duties was conducting patent searches (not so easy in the days when everything was on paper files)  and testifying on Edison’s behalf in court cases surrounding patents. Latimer was also the author of Incandescent Electric Lighting: A Practical Description of the Edison System, which was published in 1890.

 The researchers for the historical authenticity messed up on this in their attempt to reference Latimer's contribution to the lightbulb  in the seventh episode of  the HBO period drama The Gilded Age. As the events of the first season take place in 1882 -- whenLatimer was still working for his competitor -- the playful suggestion that Edison would invite Latimer to take credit could not have been made.   

In person and virtual option to learn more

Photo by Ariella Brown

If you're interested in learning more about Edison and his experiments, including the invention he did consider a failure (talking dolls),  take the time to visit Edison's lab in Menlo Park, NJ (pictured above).  It's held by the National Park Service. Find information on exhibits, hours, fees, etc., here. 

If you time it right, you can go over to see Edison's home, Glenmont, pictured here on the same day. You can also take a virtual tour.

The Lewis Latimer house is located at 34-41 137th St. Flushing, NY 11354. It, is open to the public (pay what you wish) Fridays and Saturdays 11-5.

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