curricle vs palanquin

curricle

noun
  • A light two-wheeled carriage large enough for the driver and a passenger and drawn by a carefully-matched pair. 

palanquin

noun
  • A covered type of litter for a stretched-out passenger, carried on four poles on the shoulders of four or more bearers, as formerly used (also by colonials) in eastern Asia. 

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