dissertate vs get together

dissertate

verb
  • To make a dissertation; to discourse. 

  • To write one's dissertation. 

get together

verb
  • to agree 

  • To start dating; to start being a couple. 

  • to accumulate, to gather 

  • to meet, to gather together, to congregate 

  • Used other than figuratively or idiomatically: see get, together. 

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