evaporation vs smelting

evaporation

noun
  • The process of a liquid converting to the gaseous state. 

  • The process in which all or a portion of liquid (in a container) is turned into vapour, in order to increase the concentration of solid matter in the mixture. 

smelting

noun
  • The process of melting or fusion, especially to extract a metal from its ore. 

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