Stick vs tower of strength

Stick

noun

  • A member of the Official IRA. 

name

  • The Chapman Stick, an electric musical instrument devised by Emmett Chapman. 

tower of strength

noun

  • A person who supplies strong and reliable support, especially in difficult times. 

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