horsecloth vs saddle blanket

horsecloth

noun
  • A rug or similar cloth used to cover a horse, or as part of its trappings. 

saddle blanket

noun
  • a blanket that is placed under a saddle (as a cushion and to protect the horse's back); a numnah 

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