cabriolet vs fiacre

cabriolet

noun
  • A light two- or four-wheeled carriage with a folding top, pulled by a single horse. 

  • An automobile with a retractable top. 

fiacre

noun
  • A small horse-drawn carriage for hire; a hackney carriage. 

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