Grain vs Wool

Grain

name
  • A village on the Isle of Grain, Medway borough, Kent, England (OS grid ref TQ8876). 

  • A surname. 

Wool

name
  • A village and civil parish in Dorset, England, previously in Purbeck district (OS grid ref SY8486). 

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