immure vs put in chains

immure

verb
  • To cloister, confine, imprison or hole up: to lock someone up or seclude oneself behind walls. 

  • To put or bury within a wall. 

  • To wall in. 

  • To trap or capture (an impurity); chiefly in the participial adjective immured and gerund or gerundial noun immuring. 

put in chains

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