thereby vs therewith

thereby

adv
  • By it; by that; by that means, or as a consequence of that. 

therewith

adv
  • Thereupon, forthwith; with that being said or done. 

  • In addition to that; besides, moreover. 

  • With this, that or those. 

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