fortify vs reinforce

fortify

verb
  • To impart strength or vigor to. 

  • To increase the nutritional value of food by adding ingredients. 

  • To increase the defenses of; to strengthen and secure by military works; to render defensible against an attack by hostile forces. 

  • To add spirits to wine to increase the alcohol content. 

reinforce

verb
  • To strengthen, especially by addition or augmentation. 

  • To emphasize or review. 

  • To encourage (a behavior or idea) through repeated stimulus. 

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