chimney swallow vs martin

chimney swallow

noun
  • barn swallow (Hirundo rustica) 

  • chimney swift (Chaetura pelagica) 

martin

noun
  • Any of various passerine birds of the family Hirundinidae, which also includes swallows, that catch insects whilst flying. 

  • A perforated stone-faced runner for grinding. 

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