big wheel vs merchant prince

big wheel

noun
  • A person with a great deal of power or influence, especially a high-ranking person in an organization. 

  • A Ferris wheel. 

  • A low-riding tricycle with a large front wheel. 

merchant prince

noun
  • A mercantile plutocrat: a man who wields great de facto political power by virtue of economic assets derived from trade and commerce. 

  • A prince among merchants: a wealthy and influential merchant. 

How often have the words big wheel and merchant prince occurred in a corpus of books? (source: Google Ngram Viewer )