blowgun vs flamethrower

blowgun

noun
  • A hollow tube through which a dart or similar missile may be blown. 

flamethrower

noun
  • A device that projects a flame for starting fires, and sometimes also additional fuel to help ignition. Used either as a weapon or a tool. 

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