bowstring vs send to the electric chair

bowstring

verb
  • To strangle with a bowstring. 

noun
  • The string of an archer's bow. 

  • The string of an archer's bow, as used by the Turks for strangling offenders. 

send to the electric chair

How often have the words bowstring and send to the electric chair occurred in a corpus of books? (source: Google Ngram Viewer )