bedpan vs chamber pot

bedpan

noun
  • A pan used for urination and defecation while in bed, now usually for reasons of medical necessity or convenience. 

chamber pot

noun
  • A container used for urination and defecation, particularly those used in early modern towns before the advent of the flush toilet. 

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