handspan vs middle finger

handspan

noun
  • The distance between the outstretched tips of the little finger and thumb when used as a unit of measurement 

middle finger

noun
  • The finger between the forefinger and the ring finger 

  • An obscene gesture directed towards another as an insult, made by sticking up the middle finger of a hand. 

  • An insult directed at someone. 

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