flashlight vs gas lamp

flashlight

noun
  • A battery-powered hand-held light source. 

  • A flashgun (device used to create flashes of light for photography). 

verb
  • To illuminate with a flashlight. 

gas lamp

noun
  • A lamp which operates by burning gas. 

How often have the words flashlight and gas lamp occurred in a corpus of books? (source: Google Ngram Viewer )