earmuff vs fire beater

earmuff

noun
  • A garment to keep the ears warm. 

  • A garment or part worn over a single ear. 

  • A sound-deadening cup or a pair of such cups worn over the ear or ears. 

fire beater

noun
  • A simple tool for fighting wildfires, consisting of a piece of rubber at the end of a pole. 

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