Madonna vs weaker sex

Madonna

noun
  • A morally pure woman. 

  • An artistic representation of the Virgin Mary, chiefly when holding the infant Jesus. 

name
  • The Virgin Mary, the mother of Jesus. 

  • A female given name from Italian. 

weaker sex

noun
  • Women; the female gender. 

  • Used other than figuratively or idiomatically: see weaker, sex. 

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