besides vs herewith

besides

adv
  • Also; in addition. 

  • Used to emphasize an additional point, especially an important or stronger reason; moreover; furthermore. 

  • Otherwise; else. 

prep
  • In addition to. 

  • Other than; except for; instead of. 

  • Beside, next to. 

herewith

adv
  • in this way, hereby 

  • by this means 

  • with this; especially, with this letter or communication 

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