hansom vs landau

hansom

noun
  • A Hansom cab; a carriage 

landau

noun
  • A style of automobile based around the design of landau carriages. 

  • A type of lightweight, four-wheeled carriage in which the front and back passenger seats face each other. 

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