firebomb vs tinder

firebomb

verb
  • To attack with a firebomb. 

noun
  • A weapon that causes fire; an incendiary weapon. 

tinder

verb
  • To set fire to; torch. 

noun
  • Small dry sticks and finely-divided fibrous matter etc., used to help light a fire. 

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