uncase vs unsnib

uncase

verb
  • To strip (someone); to undress. 

  • To display, or spread to view, as a flag, or the colors of a military body. 

  • To take out of a case or covering; to uncover. 

unsnib

verb
  • to undo, untie, or open or become undone, untied, or opened. 

  • Somehow she managed to unsnib the window and escape. 

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