fool vs watchman's rattle

fool

noun
  • A particular card in a tarot deck, representing a jester. 

  • A type of dessert made of puréed fruit and custard or cream. 

  • A jester; a person whose role was to entertain a sovereign and the court (or lower personages). 

  • A person with poor judgment or little intelligence. 

  • Someone who derives pleasure from something specified. 

  • Buddy, dude, man. 

verb
  • To act in an idiotic manner; to act foolishly. 

  • To trick; to deceive. 

adj
  • Foolish. 

watchman's rattle

noun
  • An instrument, with a vibrating tongue fixed in a frame, which slips over the teeth of a ratchet wheel and produces a loud raucous sound when whirled around, once used by watchmen to warn of danger 

How often have the words fool and watchman's rattle occurred in a corpus of books? (source: Google Ngram Viewer )