bilboes vs handcuffs

bilboes

noun
  • An iron bar fitting around the ankles of prisoners, and having sliding shackles. 

handcuffs

noun
  • A fastening consisting of two metal rings, designed to go around a person's wrists, and connected by a chain or hinge. 

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