embark vs set to work

embark

verb
  • To start, begin. 

  • To cause to go on board a vessel or boat; to put on shipboard. 

  • To get on a boat or ship or (outside the USA) an aeroplane. 

  • To engage, enlist, or invest (as persons, money, etc.) in any affair. 

set to work

verb
  • To begin working. 

  • To cause to begin working. 

  • To begin working at. 

How often have the words embark and set to work occurred in a corpus of books? (source: Google Ngram Viewer )