firebrand vs incendiary

firebrand

noun
  • A torch or other burning stick with a flame at one end. 

  • An argumentative troublemaker or revolutionary; one who agitates against the status quo. 

incendiary

noun
  • Something capable of causing fire, particularly a weapon. 

  • One who excites or inflames factions into quarrels. 

  • One who maliciously sets fires. 

adj
  • Intentionally stirring up strife, riot, rebellion. 

  • Capable of, or used for, or actually causing fire. 

  • Inflammatory, emotionally charged. 

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