Hadean vs infernal

Hadean

adj
  • Pertaining to Hades or hell. 

  • Of, or relating to the geological eon. 

name
  • The Hadean eon; part of the Precambrian supereon, spanning from around 4.6 to 4 billion years ago. 

infernal

adj
  • Of or relating to hell, or the world of the dead; hellish. 

  • Very annoying; damned. 

  • Of or relating to a fire or inferno. 

  • Stygian, gloomy. 

  • Diabolical or fiendish. 

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