charnel vs city of the dead

charnel

noun
  • Part of a helm, now usually identified as the hinge (near the neck) by which the helm was secured to the breastplate. 

  • A repository for dead bodies. 

  • A chapel attached to a mortuary. 

adj
  • Of or relating to a charnel, deathlike, sepulchral. 

city of the dead

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