back forty vs jerk-water

back forty

noun
  • The most remote or inaccessible part of any place. 

  • The remote part of a farm. 

jerk-water

noun
  • A branch line train, using light equipment 

adj
  • Railroads with low traffic. 

  • Of an inhabited place, small, isolated, backward. 

How often have the words back forty and jerk-water occurred in a corpus of books? (source: Google Ngram Viewer )