polytechnic vs seat of learning

polytechnic

noun
  • A three-year post-secondary vocational training institute, equivalent of community college in the U.S. or TAFE in Australia. 

adj
  • that teaches applied arts, sciences, technology, engineering and other academic subjects 

seat of learning

noun
  • An educational institution. 

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