hydrophobia vs lunacy

hydrophobia

noun
  • A morbid fear of water; aquaphobia. 

  • An aversion to water, as a symptom of rabies; the disease of rabies itself. 

lunacy

noun
  • Something deeply misguided. 

  • a cyclical mental disease, apparently linked to the lunar phases 

  • insanity implying legal irresponsibility. 

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