corroboration vs demonstration

corroboration

noun
  • That which corroborates. 

  • The act of corroborating, strengthening, or confirming; addition of strength; confirmation 

demonstration

noun
  • A proof. 

  • A public display of group opinion, such as a protest march. 

  • Expression of one's feelings by outward signs. 

  • The act of demonstrating; showing or explaining something. 

  • A prisoner's act of beating up another prisoner. 

  • An event at which something will be demonstrated. 

  • A show of military force. 

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