felo de se vs swamp water

felo de se

noun
  • A crime committed against oneself, in particular suicide 

swamp water

noun
  • Synonym of suicide (“beverage combining all available flavors at a soda fountain”) 

  • Used other than figuratively or idiomatically: see swamp, water. 

How often have the words felo de se and swamp water occurred in a corpus of books? (source: Google Ngram Viewer )