closeness vs contiguity

closeness

noun
  • The state of being close (all senses) 

  • The shortest path between two vertices in a graph 

  • The state of being friends 

  • The state of being secretive 

  • The state of being mean or stingy 

contiguity

noun
  • A state in which two or more physical objects are physically touching one another or in which sections of a plane border on one another. 

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