flak vs long Tom

flak

noun
  • Ground-based anti-aircraft guns firing explosive shells. 

  • A public-relations spokesperson. 

  • Anti-aircraft shell fire. 

  • Adverse criticism. 

long Tom

noun
  • Any of various early cannon and field guns. 

  • A high-powered lens for long-distance filming or photography. 

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