imply vs make known

imply

verb
  • to hint; to insinuate; to suggest tacitly and avoid a direct statement 

  • to suggest by logical inference 

  • to have as a necessary consequence 

make known

verb
  • To announce (some information) generally. 

  • To disclose (a secret). 

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