Bourn vs Burn

Bourn

name
  • A village in South Cambridgeshire district, Cambridgeshire, England (OS grid ref TL3256). 

  • A surname. 

Burn

name
  • A village and civil parish in Selby district, North Yorkshire, England (OS grid ref SE5928). 

  • A surname. 

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