furl vs unbind

furl

verb
  • To lower, roll up and secure (something, such as a sail or flag) 

unbind

verb
  • To set free from a debt, contract or promise. 

  • To disable some kind of connection in software, such as a key binding. 

  • To take bindings off. 

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