hit the road vs slide off

hit the road

verb
  • To leave a place; to go away. 

  • To begin traveling in an automobile or other road vehicle. 

slide off

verb
  • To leave a place, a meeting, etc., without being noticed; to slip away, slip off. 

  • Used other than figuratively or idiomatically: see slide, off. 

How often have the words hit the road and slide off occurred in a corpus of books? (source: Google Ngram Viewer )