DescriptionIrving Langmuir and Guglielmo Marconi in lab.jpg
English: Physicist Irving Langmuir(center) in his lab at General Electric in 1922, showing radio pioneer Guglielmo Marconi(right) a new 20 kW triodevacuum tube GE has developed for radio transmitters. Langmuir, a pioneer in vacuum technology and the inventor of the diffusion pump, is responsible for developing the modern "hard vacuum" radio tubes. The man on the left is Willis R. Whitney, director of GE's research lab.
This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.
This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.
Captions
Add a one-line explanation of what this file represents