ardent vs smouldering

ardent

adj
  • Providing light or heat. 

  • Full of ardor; expressing passion, spirit, or enthusiasm. 

smouldering

adj
  • Burning slowly, producing smoke but no flame. 

noun
  • The act by which something smoulders; residual heat. 

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