atrocity vs heartlessness

atrocity

noun
  • An object considered to be extremely unattractive or undesirable. 

  • An extremely cruel act; a horrid act of injustice. 

  • The quality or state of being atrocious; enormous wickedness; extreme criminality or cruelty. 

heartlessness

noun
  • the characteristic of being heartless 

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