The incandescent light bulb
On January 27, 1880, The Patent Office granted Thomas Edison’s patent for the “electric-lamp.” His patent was an improvement on electric lamps, not the invention of them, but because of Edison’s design changes and the materials he used—such as a carbon filament—his patent allowed for an electric lamp that was reliable, safe, and practical. Text adapted from “Teaching with Documents : OurDocuments.gov” in the November/December 2002 National Council for the Social Studies (NCSS) publication Social Education.
National Archives, Records of the Patent and Trademark Office
- Teaching With Documents: Alexander Graham Bell's Patent for the Telephone and Thomas Edison's Patent for the Electric Lamp
- Teaching With Documents: Petition Signed by Thomas A. Edison for Sunday Openings at the World's Columbian Exposition