sibyl vs soothsayer

sibyl

noun
  • A pagan female oracle or prophetess, especially the Cumaean sibyl. 

soothsayer

noun
  • One who predicts the future, using magic, intuition or intelligence; a diviner. 

  • A mantis or rearhorse. 

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