pliability vs viscosity

pliability

noun
  • The quality or state of being pliable; flexibility; pliableness. 

viscosity

noun
  • The state of being viscous. 

  • A tendency to prolong interpersonal encounters. 

  • A quantity expressing the magnitude of internal friction in a fluid, as measured by the force per unit area resisting uniform flow. 

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