heaviness vs smoothness

heaviness

noun
  • The state of being heavy; weight, weightiness, force of impact or gravity. 

smoothness

noun
  • The highest order of derivative (the differentiability class) over a given domain. 

  • The condition of being smooth; the degree or measure of said condition. 

  • The quantity measured by the modulus of smoothness. 

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