inspector vs magister

inspector

noun
  • A person employed to inspect something. 

  • A software tool used to examine something. 

  • A police officer ranking below superintendent. 

magister

noun
  • The possessor of a master's degree. 

  • Master; sir: a title used in the Middle Ages, given to a person in authority, or to one having a licence from a university to teach philosophy and the liberal arts. 

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