All corrections
Wikipedia May 11, 2026 at 07:48 AM

en.wikipedia.org/wiki/Edison_light_bulb

2 corrections found

1
Claim
Light bulbs with a carbon filament were first demonstrated by Thomas Edison in October 1879.
Correction

Edison was not the first to demonstrate a carbon-filament light bulb. Joseph Swan demonstrated a carbon light bulb in Newcastle on December 18, 1878, before Edison's October 1879 demonstration.

Full reasoning

This sentence incorrectly gives Edison priority for the first demonstration of a carbon-filament bulb.

The U.S. National Park Service states plainly that "Thomas Alva Edison did not invent the first light bulb" and explains that scientists had experimented with making light bulbs even before Edison was born. The Department of Energy likewise says the light bulb can't be credited to one inventor and that before Edison patented and commercialized his bulb, British inventors were already demonstrating electric light.

More specifically, the Inventing Europe history project says Joseph Swan demonstrated his carbon light bulb on December 18, 1878, nearly a year before Edison's October 1879 test. So Edison was a crucial improver and commercializer of the incandescent lamp, but he was not the first person to demonstrate a carbon-filament light bulb.

3 sources
2
Claim
These carbon filament bulbs, the first electric light bulbs, became available commercially that same year.
Correction

This sentence is doubly wrong: electric light bulbs predated Edison's 1879 lamp, and Edison's carbon-filament bulbs were commercialized in 1880, not in 1879.

Full reasoning

Two separate parts of this sentence conflict with reliable historical sources.

  1. They were not "the first electric light bulbs." The National Park Service says Edison did not invent the first light bulb, and the Department of Energy says the light bulb can't be credited to one inventor because many inventors had been working on electric light for decades before Edison.

  2. They did not become commercially available in 1879. The Department of Energy says Edison patented his bulb in 1879 and "a year later in 1880" began commercializing it. The Thomas A. Edison Papers at Rutgers likewise date the first commercial marine incandescent lighting installation to late April 1880 and the start of commercial production of electric lamps at Menlo Park to October 1, 1880.

So the article's claim that Edison's carbon-filament bulbs were the first electric light bulbs and that they were commercially available that same year (1879) is not supported by the historical record.

3 sources
Model: OPENAI_GPT_5 Prompt: v1.16.0