Dutch courage vs grog

Dutch courage

noun
  • An alcoholic drink, taken to bolster one's courage. 

  • The courage or bravado induced by alcohol. 

grog

noun
  • Any alcoholic beverage. 

  • An alcoholic beverage made with hot water or tea, sugar and rum, sometimes also with lemon or lime juice and spices, particularly cinnamon. 

  • An alcoholic beverage made with rum and water, especially that once issued to sailors of the Royal Navy. 

  • A type of pre-fired clay that has been ground and screened to a specific particle size. 

  • A glass or serving of an alcoholic beverage. 

verb
  • To grind and screen (clay) to a specific particle size. 

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