gently vs serially

gently

adv
  • In a gentle manner; to a gentle degree. 

  • Without strong force or quickness: softly, lightly. 

  • From a gentle or high-class family. 

  • Quietly: without much noise or motion. 

serially

adv
  • In series, one after the other, as opposed to in parallel. 

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