cabriolet vs dray

cabriolet

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

  • An automobile with a retractable top. 

dray

noun
  • A low horse-drawn cart, often without sides, and used especially for heavy loads. 

  • A kind of sledge or sled. 

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