foreword vs peroration

foreword

noun
  • An introductory section preceding the main text of a book or other document; a preface or introduction. 

peroration

noun
  • A discourse or rhetorical argument in general. 

  • The concluding section of a discourse, either written or oral, in which the orator or writer sums up and commends his topic to his audience, particularly as used in the technical sense of a component of ancient Roman oratorical delivery. 

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