quietness vs solitude

quietness

noun
  • Absence of disturbance; calm, stillness or serenity. 

  • Absence of sound; silence or hush. 

solitude

noun
  • Aloneness; the state of being alone, solitary, or by oneself. 

  • A lonely or deserted place. 

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