argonaut vs venturer

argonaut

noun
  • An adventurer on a dangerous but rewarding quest. 

  • Any of several species of shelled octopods of the family Argonautidae (of which only the genus Argonauta is not extinct). 

venturer

noun
  • One who ventures; a traveller or explorer. 

  • One who undertakes a business venture. 

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