derringer vs peashooter

derringer

noun
  • A type of very small, concealable pistol with one or two barrels, but without any loading system or magazine. 

peashooter

noun
  • Any small or ineffective gun. 

  • A toy gun, consisting of a tube through which peas or small objects are blown. 

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