be on one's way vs depart

be on one's way

depart

verb
  • To leave. 

  • To die. 

  • To disappear, vanish; to cease to exist. 

  • To go away from; to leave. 

  • To deviate (from), be different (from), fail to conform. 

  • To set out on a journey. 

How often have the words be on one's way and depart occurred in a corpus of books? (source: Google Ngram Viewer )