presage vs unfathom

presage

verb
  • To have a presentiment of; to feel beforehand; to foreknow. 

  • To make a prediction. 

  • To predict or foretell something. 

noun
  • A warning of a future event; an omen. 

  • An intuition of a future event; a presentiment. 

unfathom

verb
  • to come to comprehend; demystify. 

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