knight of the road vs skell

knight of the road

skell

noun
  • A male suspicious person or crime suspect, especially a street person such as a drug dealer, pimp or panhandler. 

  • a homeless person, especially one who sleeps in the New York subway. 

verb
  • To fall off or fall over. 

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