descant vs national anthem

descant

noun
  • A counterpoint melody sung or played above the theme. 

  • A lengthy discourse on a subject. 

verb
  • To sing or play a descant. 

  • To discuss at length. 

national anthem

noun
  • The official song of a constituent state of a country. 

  • The official song of a nation or sovereign state, generally of a patriotic nature and played at events to celebrate or honor said state. 

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