experiment vs galley proof

experiment

noun
  • A test under controlled conditions made to either demonstrate a known truth, examine the validity of a hypothesis, or determine the efficacy or likelihood of something previously untried. 

verb
  • To conduct an experiment. 

galley proof

noun
  • A trial page or proof of continuous text that has not been divided into pages. 

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