galvanism vs wattage

galvanism

noun
  • The chemical generation of electricity. 

  • The therapeutic use of electricity directly applied to the body. 

wattage

noun
  • The power requirement of some electric appliance. 

  • An amount or power (especially electric), expressed in watts, kilowatts etc. 

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