elevate vs heighten

elevate

verb
  • To raise (something) to a higher position. 

  • To direct (the mind, thoughts, etc.) toward more worthy things. 

  • To confer honor or nobility on (someone). 

  • To promote (someone) to a higher rank. 

  • To make (something or someone) more worthy or of greater value. 

  • To increase the intensity or degree of (something). 

heighten

verb
  • To make high; to raise higher; to elevate. 

  • To advance, increase, augment, make larger, more intense, stronger etc. 

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