Tag Archives: Thomas Edison

How Many Filaments Did Edison Test for His Lightbulb?

People know America’s great inventor Thomas Edison went through multitudes of material to find a good filament for his little light bulb hobby. He tested everything he could get his hands on and thought could work. Some even claim he made a large bulb in order to test the illumination of a charged cat.*

The Edison Museum states his team tested over 6,000 plant materials, many of them carbonized. The Franklin Institute makes the same claim, possibly taking it from the same source though that source isn’t clearly cited.

Rutgers Edison Papers says no one, not even the inventor himself, kept count of how many times they tried this or that. They quote an 1890 interview in which Edison says they tried 3,000 different theories in working out a functional and affordable light bulb, and many more experiments were conducted after they had a patent and a production factory. Edison was awarded that patent on January 27, 1880.

The number of filament experiment may be lost to history, as well as whether he actually said one of his famous quotations:

Genius is one percent inspiration, ninety-nine percent perspiration.

– Thomas Edison or Harper’s Monthly?

Ralph Keyes, in his book The Quote Verifier, notes this quote and its variations can be attributed to Edison, but the earliest version of this can be found in an 1898 Ladies Home Journal. (Check to see if you still have this edition on your TBR pile.) The magazine claims Edison offered two percent inspiration and ninety-eight percent perspiration as a formula for genius. In the years that followed, it seemed magazine writers, not the inventor, were repeating this line in different ways, but by 1932 Edison claimed it as his own.

Update: The 1932 Harper’s Monthly interview referred to above may have been a contemporary interview, an obituary, or a tribute, because the inventor died in 1931. Harper’s doesn’t make it’s archives available online for free, but I have found a citation it, saying it was the September issue of Harper’s and that Edison was thought to have said this in 1903.

Photo by Rahul from Pexels

* no one claims this.