librate vs tip the scales

librate

verb
  • To be poised; to balance oneself. 

  • To oscillate (like the beam of a balance). 

noun
  • A piece of land having a value of one pound per year. 

tip the scales

verb
  • To turn to one side a balanced situation. 

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