chip in vs put one's oar in

chip in

verb
  • To interrupt a discussion for the purpose of making a comment. 

  • To put a chip shot in the hole. 

  • To make a contribution; help in a small way; especially, to pay for a part of something. 

  • To contribute. 

  • To ante; to put into the pot the amount of chips or money required to continue. 

put one's oar in

verb
  • Synonym of stick one's oar in (“to interfere”) 

How often have the words chip in and put one's oar in occurred in a corpus of books? (source: Google Ngram Viewer )