bombproof vs treated

bombproof

verb
  • To make resistant to bomb blasts. 

adj
  • Sufficiently strong to resist the effects of a blast from a bomb. 

noun
  • An air-raid shelter, a structure designed to give protection against air raids and bombs. 

treated

adj
  • Subject to treatment or an action. 

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