malleate vs stiffen

malleate

verb
  • To beat into shape with a hammer. 

adj
  • Possessing or resembling a malleus, or another structure shaped like a hammer. 

  • Having a surface with shallow round indentations, resembling copper that has been hammered. 

stiffen

verb
  • To make stiff. 

  • To become stiff. 

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