cropper vs reaper

cropper

noun
  • A person who nurtures and gathers a crop. 

  • A fall, a tumble; a decided failure. 

  • A variety of plant producing a good harvest. 

  • A machine for cropping, as for shearing off bolts or rod iron, or for facing cloth. 

  • A breed of domestic pigeon with large crop. 

reaper

noun
  • One who reaps; a person employed to harvest crops from the fields by reaping. 

  • The recluse spider (Loxosceles and Sicarius spp.). 

  • A machine used to harvest crops. 

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