Jack Ketch vs mortality

Jack Ketch

noun

  • death 

  • the gallows 

  • a public executioner 

  • the devil 

mortality

noun

  • Death. 

  • The number of deaths per given unit of population over a given period of time. 

  • Deaths resulting from an event (such as a war, epidemic or disaster). 

  • The state of being susceptible to death. 

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