loupe vs magnifying glass

loupe

noun
  • A magnifying glass, usually mounted in an eyepiece, often used by jewellers and watchmakers. 

  • A type of short-range binoculars used by surgeons and dentists. 

magnifying glass

noun
  • An instrument made of convex glass, used to magnify. 

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